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• SQL SERVER – Developer Training Resources and Summary Roundup

  - by pinaldave

  It is always pleasure for any author when other renowned authors in the industry write about you. Earlier I wrote a five part blog series on Developer Training and I have received a phenomenal response to the series. I have received plenty of comments, questions and feedback. I thought it would be nice to sum up the whole series as well answer a few of the questions received. Quick Recap Developer Training - Importance and Significance - Part 1 In this part we discussed the importance of training in the real world. The most important and valuable resource any company is its employee. Employees who have been well-trained will be better at their jobs and produce a better product.  An employee who is well trained obviously knows more about their job and all the technical aspects. I have a very high opinion about training employees and it is the most important task. Developer Training – Employee Morals and Ethics – Part 2 In this part we discussed the most crucial components of training. Often employees are expecting the company to pay for their training and the company expresses no interest in training the employee. Quite often training expenses are the real issue for both the employee and employer. There are companies that pay for 100% of the expenses and there are employees who opt for training on their own expense during their personal time. Training is often looked at as vacation by employee and employers and we need to change this mind-set. One of the ways is to report back the learning to your manager and implement newly learned knowledge in day-to-day work. Developer Training – Difficult Questions and Alternative Perspective - Part 3 This part was the most difficult to write as I tried to address a few difficult questions and answers. Training is such a sensitive issue that many developers when not receiving chance for training think about leaving the organization. The manager often feels pressure to accommodate every single employee for training even though his training budget is limited. It is indeed the responsibility of the developer to get maximum advantage from the training. Training immediately helps organizations but stays as a part of an employee’s knowledge forever. Developer Training – Various Options for Developer Training – Part 4 In this part I tried to explore a few methods and options for training. The generic feedback I received on this blog post was short and I should have explored each of the subject of the training in details. I believe there are two big buckets of training 1) Instructor Lead Training and 2) Self Lead Training. The common element between both the methods is “learning material”. Learning material can be of any format – videos, books, paper notes or just a plain black board. Instructor-led training is a very effective mode but not possible every single time. During the course of the developer’s career, one has to learn lots of new technology and it is almost impossible to have a quality trainer available on that subject at that time. Books are most effective and proven methods, however, it always helps if someone explains the concepts of the book with a demonstration. In recent times I have started to believe in online trainings which leads to a hybrid experience. Online trainings take the best part of the books and the best part of the instructor-led training and gives effective training in a matter of hours. Developer Training – A Conclusive Summary- Part 5 In this part, I shared what I was continuously thinking about developer training. There is no better teacher than oneself. There is no better motivation than a personal desire to learn new technology. Honestly there is nothing more personal learning. That “change is the only constant” and “adapt & overcome” are the essential lessons of life. One cannot stop the learning and resist the change. In the IT industry “ego of knowing all” and the “resistance to change” are the most challenging issues. Once someone overcomes them, life is much easier. I believe that proper and appropriate high quality training can help to address the burning issues. Opinion of Friends I invited a few of my friends to express their opinion about developer training and here are their opinions. I am listing them here in the order of the blog post publishing date. Nakul Vachhrajani - Developer Trainings-Importance, Benefits, Tips and follow-up Nakul’s sums of many of the concepts which are complementary to my blog posts. Nakul addresses the burning question of developer training with different angles. I am personally very impressed by his following statement - “Being skilled does not mean having just a stack of certifications, but it also means having an understanding about the internals of the products that you are working on – and using that knowledge to improve the efficiency & productivity at the workplace in turn resulting in better products, better consulting abilities and a happier self.” Nakul also suggests the online training options of Pluralsight. Vinod Kumar - Training–a necessity or bonus Vinod Kumar comes up with excellent follow up on developer training. Vinod is known for his inspirational writing about SQL Server. Vinod starts with a story of a student who is extremely eager to learn the wisdom of life from a monk but the monk does not accept him as a disciple for a long time. The conversation between student and monk is indeed an essence of all learning. We all want to learn quickly and be successful but the most important thing in life is to have the right attitude towards learning and more so towards life. The blog post end with a very important thought about how to avoid the famous excuse – “I don’t have enough time.” Ritesh Shah - Training – useful or useless? Ritesh brings up very important concept related to training. Ritesh in his meticulous style explains why training is an important and lifelong process. Training must not stop at any age but should continue forever. The moment training stops, progress stops along with. Paras Doshi - Professional Development Resource Paras is known for his to–the-point writing, and has summarized the five part series very precisely. He read the five part series and created a digest summary of the blog post. If you are in a rush and have no time to read my five series – I suggest you read his blog post. Training Resources I am often asked what the best resources for learning new technology are. This is the most difficult question EVER. There are plenty of good training resources available. When it is about training our needs are different, our preference of learning is different and we all have an opinion. Additionally, we all are located in different geographic locations worldwide and there is no way one solution will fit all. However, let me list a few of the training resources which I have built so far and you can consume them if you find it relevant to your need. SQL Server Books SQL Server Interview Questions and Answers SQL Wait Stats SQL Programming Joes 2 Pros SQL Server Video Tutorials SQL Server Questions and Answers SQL Server Performance: Indexing Basics SQL Server Performance: Introduction to Query Tuning SQL in Sixty Seconds Series of Sixty Seconds Learning Video on YouTube Trust me worldwide web is very big and there are plenty of high quality learning materials available worldwide – trainer-led as well online. I suggest you explore various options and make the best choice for yourself. Remember, training is your personal journey and it should never stop. Are you ready? Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Developer Training, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• A Taxonomy of Numerical Methods v1

  - by JoshReuben

  Numerical Analysis – When, What, (but not how) Once you understand the Math & know C++, Numerical Methods are basically blocks of iterative & conditional math code. I found the real trick was seeing the forest for the trees – knowing which method to use for which situation. Its pretty easy to get lost in the details – so I’ve tried to organize these methods in a way that I can quickly look this up. I’ve included links to detailed explanations and to C++ code examples. I’ve tried to classify Numerical methods in the following broad categories: Solving Systems of Linear Equations Solving Non-Linear Equations Iteratively Interpolation Curve Fitting Optimization Numerical Differentiation & Integration Solving ODEs Boundary Problems Solving EigenValue problems Enjoy – I did ! Solving Systems of Linear Equations Overview Solve sets of algebraic equations with x unknowns The set is commonly in matrix form Gauss-Jordan Elimination http://en.wikipedia.org/wiki/Gauss%E2%80%93Jordan_elimination C++: http://www.codekeep.net/snippets/623f1923-e03c-4636-8c92-c9dc7aa0d3c0.aspx Produces solution of the equations & the coefficient matrix Efficient, stable 2 steps: · Forward Elimination – matrix decomposition: reduce set to triangular form (0s below the diagonal) or row echelon form. If degenerate, then there is no solution · Backward Elimination –write the original matrix as the product of ints inverse matrix & its reduced row-echelon matrix à reduce set to row canonical form & use back-substitution to find the solution to the set Elementary ops for matrix decomposition: · Row multiplication · Row switching · Add multiples of rows to other rows Use pivoting to ensure rows are ordered for achieving triangular form LU Decomposition http://en.wikipedia.org/wiki/LU_decomposition C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-lu-decomposition-for-solving.html Represent the matrix as a product of lower & upper triangular matrices A modified version of GJ Elimination Advantage – can easily apply forward & backward elimination to solve triangular matrices Techniques: · Doolittle Method – sets the L matrix diagonal to unity · Crout Method - sets the U matrix diagonal to unity Note: both the L & U matrices share the same unity diagonal & can be stored compactly in the same matrix Gauss-Seidel Iteration http://en.wikipedia.org/wiki/Gauss%E2%80%93Seidel_method C++: http://www.nr.com/forum/showthread.php?t=722 Transform the linear set of equations into a single equation & then use numerical integration (as integration formulas have Sums, it is implemented iteratively). an optimization of Gauss-Jacobi: 1.5 times faster, requires 0.25 iterations to achieve the same tolerance Solving Non-Linear Equations Iteratively find roots of polynomials – there may be 0, 1 or n solutions for an n order polynomial use iterative techniques Iterative methods · used when there are no known analytical techniques · Requires set functions to be continuous & differentiable · Requires an initial seed value – choice is critical to convergence à conduct multiple runs with different starting points & then select best result · Systematic - iterate until diminishing returns, tolerance or max iteration conditions are met · bracketing techniques will always yield convergent solutions, non-bracketing methods may fail to converge Incremental method if a nonlinear function has opposite signs at 2 ends of a small interval x1 & x2, then there is likely to be a solution in their interval – solutions are detected by evaluating a function over interval steps, for a change in sign, adjusting the step size dynamically. Limitations – can miss closely spaced solutions in large intervals, cannot detect degenerate (coinciding) solutions, limited to functions that cross the x-axis, gives false positives for singularities Fixed point method http://en.wikipedia.org/wiki/Fixed-point_iteration C++: http://books.google.co.il/books?id=weYj75E_t6MC&pg=PA79&lpg=PA79&dq=fixed+point+method++c%2B%2B&source=bl&ots=LQ-5P_taoC&sig=lENUUIYBK53tZtTwNfHLy5PEWDk&hl=en&sa=X&ei=wezDUPW1J5DptQaMsIHQCw&redir_esc=y#v=onepage&q=fixed%20point%20method%20%20c%2B%2B&f=false Algebraically rearrange a solution to isolate a variable then apply incremental method Bisection method http://en.wikipedia.org/wiki/Bisection_method C++: http://numericalcomputing.wordpress.com/category/algorithms/ Bracketed - Select an initial interval, keep bisecting it ad midpoint into sub-intervals and then apply incremental method on smaller & smaller intervals – zoom in Adv: unaffected by function gradient à reliable Disadv: slow convergence False Position Method http://en.wikipedia.org/wiki/False_position_method C++: http://www.dreamincode.net/forums/topic/126100-bisection-and-false-position-methods/ Bracketed - Select an initial interval , & use the relative value of function at interval end points to select next sub-intervals (estimate how far between the end points the solution might be & subdivide based on this) Newton-Raphson method http://en.wikipedia.org/wiki/Newton's_method C++: http://www-users.cselabs.umn.edu/classes/Summer-2012/csci1113/index.php?page=./newt3 Also known as Newton's method Convenient, efficient Not bracketed – only a single initial guess is required to start iteration – requires an analytical expression for the first derivative of the function as input. Evaluates the function & its derivative at each step. Can be extended to the Newton MutiRoot method for solving multiple roots Can be easily applied to an of n-coupled set of non-linear equations – conduct a Taylor Series expansion of a function, dropping terms of order n, rewrite as a Jacobian matrix of PDs & convert to simultaneous linear equations !!! Secant Method http://en.wikipedia.org/wiki/Secant_method C++: http://forum.vcoderz.com/showthread.php?p=205230 Unlike N-R, can estimate first derivative from an initial interval (does not require root to be bracketed) instead of inputting it Since derivative is approximated, may converge slower. Is fast in practice as it does not have to evaluate the derivative at each step. Similar implementation to False Positive method Birge-Vieta Method http://mat.iitm.ac.in/home/sryedida/public_html/caimna/transcendental/polynomial%20methods/bv%20method.html C++: http://books.google.co.il/books?id=cL1boM2uyQwC&pg=SA3-PA51&lpg=SA3-PA51&dq=Birge-Vieta+Method+c%2B%2B&source=bl&ots=QZmnDTK3rC&sig=BPNcHHbpR_DKVoZXrLi4nVXD-gg&hl=en&sa=X&ei=R-_DUK2iNIjzsgbE5ID4Dg&redir_esc=y#v=onepage&q=Birge-Vieta%20Method%20c%2B%2B&f=false combines Horner's method of polynomial evaluation (transforming into lesser degree polynomials that are more computationally efficient to process) with Newton-Raphson to provide a computational speed-up Interpolation Overview Construct new data points for as close as possible fit within range of a discrete set of known points (that were obtained via sampling, experimentation) Use Taylor Series Expansion of a function f(x) around a specific value for x Linear Interpolation http://en.wikipedia.org/wiki/Linear_interpolation C++: http://www.hamaluik.com/?p=289 Straight line between 2 points à concatenate interpolants between each pair of data points Bilinear Interpolation http://en.wikipedia.org/wiki/Bilinear_interpolation C++: http://supercomputingblog.com/graphics/coding-bilinear-interpolation/2/ Extension of the linear function for interpolating functions of 2 variables – perform linear interpolation first in 1 direction, then in another. Used in image processing – e.g. texture mapping filter. Uses 4 vertices to interpolate a value within a unit cell. Lagrange Interpolation http://en.wikipedia.org/wiki/Lagrange_polynomial C++: http://www.codecogs.com/code/maths/approximation/interpolation/lagrange.php For polynomials Requires recomputation for all terms for each distinct x value – can only be applied for small number of nodes Numerically unstable Barycentric Interpolation http://epubs.siam.org/doi/pdf/10.1137/S0036144502417715 C++: http://www.gamedev.net/topic/621445-barycentric-coordinates-c-code-check/ Rearrange the terms in the equation of the Legrange interpolation by defining weight functions that are independent of the interpolated value of x Newton Divided Difference Interpolation http://en.wikipedia.org/wiki/Newton_polynomial C++: http://jee-appy.blogspot.co.il/2011/12/newton-divided-difference-interpolation.html Hermite Divided Differences: Interpolation polynomial approximation for a given set of data points in the NR form - divided differences are used to approximately calculate the various differences. For a given set of 3 data points , fit a quadratic interpolant through the data Bracketed functions allow Newton divided differences to be calculated recursively Difference table Cubic Spline Interpolation http://en.wikipedia.org/wiki/Spline_interpolation C++: https://www.marcusbannerman.co.uk/index.php/home/latestarticles/42-articles/96-cubic-spline-class.html Spline is a piecewise polynomial Provides smoothness – for interpolations with significantly varying data Use weighted coefficients to bend the function to be smooth & its 1st & 2nd derivatives are continuous through the edge points in the interval Curve Fitting A generalization of interpolating whereby given data points may contain noise à the curve does not necessarily pass through all the points Least Squares Fit http://en.wikipedia.org/wiki/Least_squares C++: http://www.ccas.ru/mmes/educat/lab04k/02/least-squares.c Residual – difference between observed value & expected value Model function is often chosen as a linear combination of the specified functions Determines: A) The model instance in which the sum of squared residuals has the least value B) param values for which model best fits data Straight Line Fit Linear correlation between independent variable and dependent variable Linear Regression http://en.wikipedia.org/wiki/Linear_regression C++: http://www.oocities.org/david_swaim/cpp/linregc.htm Special case of statistically exact extrapolation Leverage least squares Given a basis function, the sum of the residuals is determined and the corresponding gradient equation is expressed as a set of normal linear equations in matrix form that can be solved (e.g. using LU Decomposition) Can be weighted - Drop the assumption that all errors have the same significance –-> confidence of accuracy is different for each data point. Fit the function closer to points with higher weights Polynomial Fit - use a polynomial basis function Moving Average http://en.wikipedia.org/wiki/Moving_average C++: http://www.codeproject.com/Articles/17860/A-Simple-Moving-Average-Algorithm Used for smoothing (cancel fluctuations to highlight longer-term trends & cycles), time series data analysis, signal processing filters Replace each data point with average of neighbors. Can be simple (SMA), weighted (WMA), exponential (EMA). Lags behind latest data points – extra weight can be given to more recent data points. Weights can decrease arithmetically or exponentially according to distance from point. Parameters: smoothing factor, period, weight basis Optimization Overview Given function with multiple variables, find Min (or max by minimizing –f(x)) Iterative approach Efficient, but not necessarily reliable Conditions: noisy data, constraints, non-linear models Detection via sign of first derivative - Derivative of saddle points will be 0 Local minima Bisection method Similar method for finding a root for a non-linear equation Start with an interval that contains a minimum Golden Search method http://en.wikipedia.org/wiki/Golden_section_search C++: http://www.codecogs.com/code/maths/optimization/golden.php Bisect intervals according to golden ratio 0.618.. Achieves reduction by evaluating a single function instead of 2 Newton-Raphson Method Brent method http://en.wikipedia.org/wiki/Brent's_method C++: http://people.sc.fsu.edu/~jburkardt/cpp_src/brent/brent.cpp Based on quadratic or parabolic interpolation – if the function is smooth & parabolic near to the minimum, then a parabola fitted through any 3 points should approximate the minima – fails when the 3 points are collinear , in which case the denominator is 0 Simplex Method http://en.wikipedia.org/wiki/Simplex_algorithm C++: http://www.codeguru.com/cpp/article.php/c17505/Simplex-Optimization-Algorithm-and-Implemetation-in-C-Programming.htm Find the global minima of any multi-variable function Direct search – no derivatives required At each step it maintains a non-degenerative simplex – a convex hull of n+1 vertices. Obtains the minimum for a function with n variables by evaluating the function at n-1 points, iteratively replacing the point of worst result with the point of best result, shrinking the multidimensional simplex around the best point. Point replacement involves expanding & contracting the simplex near the worst value point to determine a better replacement point Oscillation can be avoided by choosing the 2nd worst result Restart if it gets stuck Parameters: contraction & expansion factors Simulated Annealing http://en.wikipedia.org/wiki/Simulated_annealing C++: http://code.google.com/p/cppsimulatedannealing/ Analogy to heating & cooling metal to strengthen its structure Stochastic method – apply random permutation search for global minima - Avoid entrapment in local minima via hill climbing Heating schedule - Annealing schedule params: temperature, iterations at each temp, temperature delta Cooling schedule – can be linear, step-wise or exponential Differential Evolution http://en.wikipedia.org/wiki/Differential_evolution C++: http://www.amichel.com/de/doc/html/ More advanced stochastic methods analogous to biological processes: Genetic algorithms, evolution strategies Parallel direct search method against multiple discrete or continuous variables Initial population of variable vectors chosen randomly – if weighted difference vector of 2 vectors yields a lower objective function value then it replaces the comparison vector Many params: #parents, #variables, step size, crossover constant etc Convergence is slow – many more function evaluations than simulated annealing Numerical Differentiation Overview 2 approaches to finite difference methods: · A) approximate function via polynomial interpolation then differentiate · B) Taylor series approximation – additionally provides error estimate Finite Difference methods http://en.wikipedia.org/wiki/Finite_difference_method C++: http://www.wpi.edu/Pubs/ETD/Available/etd-051807-164436/unrestricted/EAMPADU.pdf Find differences between high order derivative values - Approximate differential equations by finite differences at evenly spaced data points Based on forward & backward Taylor series expansion of f(x) about x plus or minus multiples of delta h. Forward / backward difference - the sums of the series contains even derivatives and the difference of the series contains odd derivatives – coupled equations that can be solved. Provide an approximation of the derivative within a O(h^2) accuracy There is also central difference & extended central difference which has a O(h^4) accuracy Richardson Extrapolation http://en.wikipedia.org/wiki/Richardson_extrapolation C++: http://mathscoding.blogspot.co.il/2012/02/introduction-richardson-extrapolation.html A sequence acceleration method applied to finite differences Fast convergence, high accuracy O(h^4) Derivatives via Interpolation Cannot apply Finite Difference method to discrete data points at uneven intervals – so need to approximate the derivative of f(x) using the derivative of the interpolant via 3 point Lagrange Interpolation Note: the higher the order of the derivative, the lower the approximation precision Numerical Integration Estimate finite & infinite integrals of functions More accurate procedure than numerical differentiation Use when it is not possible to obtain an integral of a function analytically or when the function is not given, only the data points are Newton Cotes Methods http://en.wikipedia.org/wiki/Newton%E2%80%93Cotes_formulas C++: http://www.siafoo.net/snippet/324 For equally spaced data points Computationally easy – based on local interpolation of n rectangular strip areas that is piecewise fitted to a polynomial to get the sum total area Evaluate the integrand at n+1 evenly spaced points – approximate definite integral by Sum Weights are derived from Lagrange Basis polynomials Leverage Trapezoidal Rule for default 2nd formulas, Simpson 1/3 Rule for substituting 3 point formulas, Simpson 3/8 Rule for 4 point formulas. For 4 point formulas use Bodes Rule. Higher orders obtain more accurate results Trapezoidal Rule uses simple area, Simpsons Rule replaces the integrand f(x) with a quadratic polynomial p(x) that uses the same values as f(x) for its end points, but adds a midpoint Romberg Integration http://en.wikipedia.org/wiki/Romberg's_method C++: http://code.google.com/p/romberg-integration/downloads/detail?name=romberg.cpp&can=2&q= Combines trapezoidal rule with Richardson Extrapolation Evaluates the integrand at equally spaced points The integrand must have continuous derivatives Each R(n,m) extrapolation uses a higher order integrand polynomial replacement rule (zeroth starts with trapezoidal) à a lower triangular matrix set of equation coefficients where the bottom right term has the most accurate approximation. The process continues until the difference between 2 successive diagonal terms becomes sufficiently small. Gaussian Quadrature http://en.wikipedia.org/wiki/Gaussian_quadrature C++: http://www.alglib.net/integration/gaussianquadratures.php Data points are chosen to yield best possible accuracy – requires fewer evaluations Ability to handle singularities, functions that are difficult to evaluate The integrand can include a weighting function determined by a set of orthogonal polynomials. Points & weights are selected so that the integrand yields the exact integral if f(x) is a polynomial of degree <= 2n+1 Techniques (basically different weighting functions): · Gauss-Legendre Integration w(x)=1 · Gauss-Laguerre Integration w(x)=e^-x · Gauss-Hermite Integration w(x)=e^-x^2 · Gauss-Chebyshev Integration w(x)= 1 / Sqrt(1-x^2) Solving ODEs Use when high order differential equations cannot be solved analytically Evaluated under boundary conditions RK for systems – a high order differential equation can always be transformed into a coupled first order system of equations Euler method http://en.wikipedia.org/wiki/Euler_method C++: http://rosettacode.org/wiki/Euler_method First order Runge–Kutta method. Simple recursive method – given an initial value, calculate derivative deltas. Unstable & not very accurate (O(h) error) – not used in practice A first-order method - the local error (truncation error per step) is proportional to the square of the step size, and the global error (error at a given time) is proportional to the step size In evolving solution between data points xn & xn+1, only evaluates derivatives at beginning of interval xn à asymmetric at boundaries Higher order Runge Kutta http://en.wikipedia.org/wiki/Runge%E2%80%93Kutta_methods C++: http://www.dreamincode.net/code/snippet1441.htm 2nd & 4th order RK - Introduces parameterized midpoints for more symmetric solutions à accuracy at higher computational cost Adaptive RK – RK-Fehlberg – estimate the truncation at each integration step & automatically adjust the step size to keep error within prescribed limits. At each step 2 approximations are compared – if in disagreement to a specific accuracy, the step size is reduced Boundary Value Problems Where solution of differential equations are located at 2 different values of the independent variable x à more difficult, because cannot just start at point of initial value – there may not be enough starting conditions available at the end points to produce a unique solution An n-order equation will require n boundary conditions – need to determine the missing n-1 conditions which cause the given conditions at the other boundary to be satisfied Shooting Method http://en.wikipedia.org/wiki/Shooting_method C++: http://ganeshtiwaridotcomdotnp.blogspot.co.il/2009/12/c-c-code-shooting-method-for-solving.html Iteratively guess the missing values for one end & integrate, then inspect the discrepancy with the boundary values of the other end to adjust the estimate Given the starting boundary values u1 & u2 which contain the root u, solve u given the false position method (solving the differential equation as an initial value problem via 4th order RK), then use u to solve the differential equations. Finite Difference Method For linear & non-linear systems Higher order derivatives require more computational steps – some combinations for boundary conditions may not work though Improve the accuracy by increasing the number of mesh points Solving EigenValue Problems An eigenvalue can substitute a matrix when doing matrix multiplication à convert matrix multiplication into a polynomial EigenValue For a given set of equations in matrix form, determine what are the solution eigenvalue & eigenvectors Similar Matrices - have same eigenvalues. Use orthogonal similarity transforms to reduce a matrix to diagonal form from which eigenvalue(s) & eigenvectors can be computed iteratively Jacobi method http://en.wikipedia.org/wiki/Jacobi_method C++: http://people.sc.fsu.edu/~jburkardt/classes/acs2_2008/openmp/jacobi/jacobi.html Robust but Computationally intense – use for small matrices < 10x10 Power Iteration http://en.wikipedia.org/wiki/Power_iteration For any given real symmetric matrix, generate the largest single eigenvalue & its eigenvectors Simplest method – does not compute matrix decomposition à suitable for large, sparse matrices Inverse Iteration Variation of power iteration method – generates the smallest eigenvalue from the inverse matrix Rayleigh Method http://en.wikipedia.org/wiki/Rayleigh's_method_of_dimensional_analysis Variation of power iteration method Rayleigh Quotient Method Variation of inverse iteration method Matrix Tri-diagonalization Method Use householder algorithm to reduce an NxN symmetric matrix to a tridiagonal real symmetric matrix vua N-2 orthogonal transforms     Whats Next Outside of Numerical Methods there are lots of different types of algorithms that I’ve learned over the decades: Data Mining – (I covered this briefly in a previous post: http://geekswithblogs.net/JoshReuben/archive/2007/12/31/ssas-dm-algorithms.aspx ) Search & Sort Routing Problem Solving Logical Theorem Proving Planning Probabilistic Reasoning Machine Learning Solvers (eg MIP) Bioinformatics (Sequence Alignment, Protein Folding) Quant Finance (I read Wilmott’s books – interesting) Sooner or later, I’ll cover the above topics as well.

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• Tools to Help Post Content On Your WordPress Blog

  - by Matthew Guay

  Now that you’ve got a nice blog, you want to do more with it and start posting content.  Here we look at some tools that will allow you to post directly to your WordPress blog. Writing a new blog post is easy with WordPress as we saw in our previous post about Starting your own WordPress blog.  The web editor gives you a lot of features and even lets you edit your post’s source code if you enjoy hacking HTML.  There are other tools that will allow you to post content, here we look at how you can post with dedicated apps, browser plugins, and even by email. Windows Live Writer Windows Live Writer (part of the Windows Live Essentials Suite) is a great app for posting content to your blog.  This free program for Microsoft lets you post content to a variety of blogging services, including Blogger, Typepad, LiveJournal, and of course WordPress.  You can write blog posts directly from its Word-like editor, complete with pictures and advanced formatting.  Even if you’re offline, you can still write posts and save them for when you’re online again. For more information about installing Live writer, check out our article on how to Install Windows Live Essentials In Windows 7. Once Live Writer is installed, open it to add your blog.  If you already had Live Writer installed and configured for a blog, you can add your new blog, too.  Just click your blog’s name in the top right corner, and select “Add blog account”. Select “Other blog service” to add your WordPress blog to Writer, and click Next.   Enter your blog’s web address, and your username and password.  Check Remember my password so you don’t have to enter it every time you write something. Writer will analyze your blog and setup your account. During the setup process it may ask to post a temporary post.  This will let you preview blog posts using your blog’s real theme, which is helpful, so click Yes. Finally, add your Blog’s name, and click Finish. You can now use the rich editor to write and add content to a new blog post.   Select the Preview tab to see how your post will look on your blog… Or, if you’re a HTML geek, select the Source tab to edit the code of your blog post. From the bottom of the window, you can choose categories, insert tags, and even schedule the post to publish on a different day.  Live Writer is fully integrated with WordPress; you’re not missing anything by using the desktop editor. If you want to edit a post you’ve already published, click the Open button and select the post.  You can chose and edit any post, including ones you published via the web interface or other editors. Add Multimedia Content to your Posts with Live Writer Back in the Edit tab, you can add pictures, videos and more from the sidebar.  Select what you want to insert. Pictures If you insert a picture, you can add many nice borders and designs to it. Or, you can even add artistic effects from the Effects tab in the sidebar. Photo Gallery If you want to post several pictures, say some of your vacation shots, then inserting a picture gallery may be the best option.  Select Insert Photo Gallery in the sidebar, and then choose the pictures you want in the gallery. Once the gallery is inserted, you can choose from several styles to showcase your pictures. When you post the blog, you will be asked to sign in with your Windows Live ID as the gallery pictures will be stored in the free Skydrive storage service. Your blog readers can see the preview of your pictures directly on your blog, and then can view each individual picture, download them, or see a slideshow online via the link. Video If you want to add a video to your blog post, select Video from the sidebar as above.  You can select a video that’s already online, or you can choose a new video from file and upload it via YouTube directly from Windows Live Writer.   Note that you will have to sign in with your YouTube account to upload videos to YouTube, so if you’re not logged in you’ll be prompted to do so when you click Insert. Geek Tip:  If you ever want to copy your Live Writer settings to another computer, check out our article on how to Backup Your Windows Live Writer Settings. Microsoft Office Word Word 2007 and 2010 also let you post content directly to your blog.  This is especially nice if you’ve already typed up a document and think it would be good on your Blog as well.  Check out our in-depth tutorial on posting blog posts via Word 2007 using Word 2007 as a blogging tool. This works in Word 2010 too, except the Office Orb has been replaced by the new Backstage view.  So, in Word 2010, to start a new blog post, click File \ New then select Blog post.  Proceed as you would in Word 2007 to add your blog settings and post the content you want. Or, if you’ve already written a document and want to post it, select File \ Share (or Save and Send in the final version of Word 2010), and then click Publish as Blog Post.  If you haven’t setup your blog account yet, set it up as shown in the Word 2007 article. Post Via Email Most of us use email daily, and already have our favorite email app or service.  Whether on your desktop or mobile phone, it’s easy to create rich emails and add content.  WordPress lets you generate a unique email address that you can use to easily post content and email to your blog.  Just compose your email with the subject as the title of your post, and send it to this unique address.  Your new post will be up in minutes. To active this feature, click the My Account button in the top menu bar in your WordPress.com account, and select My Blogs. Click the Enable button under Post by Email beside your blog’s name.   Now you’ll have a private email you can use to post to your blog.  Anything you send to this email will be posted as a new post.  If you think your email may be compromised, click Regenerate to get a new publishing email address. Any email program or webapp now is a blog post editor.  Feel free to use rich formatting or insert pictures; it all comes through great.  This is also a great way to post to your blog from your mobile device.  Whether you’re using webmail or a dedicated email client on your phone, you can now blog from anywhere.   Mobile Applications WordPress also offer dedicated applications for blogging directly from your mobile device.  You can write new posts, edit existing ones, and manage comments all from your Smartphone.  Currently they offer apps for iPhone, Android, and Blackberry.  Check them out at the link below. Conclusion Whether you want to write from your browser or email a post to your blog, WordPress is flexible enough to work right along with your preferences.  However you post, you can be sure that it will look professional and be easily accessible with your WordPress blog. Download Windows Live Writer Download WordPress apps for your mobile device Similar Articles Productive Geek Tips Quick Tip: Set a Future Date for a Post in WordPressAdd Social Bookmarking (Digg This!) Links to your Wordpress BlogFuture Date a Post in Windows Live WriterHow To Start Your Own Professional Blog with WordPressUsing Word 2007 as a Blogging Tool TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Acronis Online Backup DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows Fun with 47 charts and graphs Tomorrow is Mother’s Day Check the Average Speed of YouTube Videos You’ve Watched OutlookStatView Scans and Displays General Usage Statistics How to Add Exceptions to the Windows Firewall Office 2010 reviewed in depth by Ed Bott

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• How Mary Meeker’s Latest Findings May Make You Re-Imagine Commerce

  - by Brenna Johnson-Oracle

  0 0 1 954 5439 Endeca Technologies 45 12 6381 14.0 Normal 0 false false false EN-US JA X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:Cambria; mso-ascii-font-family:Cambria; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Cambria; mso-hansi-theme-font:minor-latin;} Today, Mary Meeker released her highly anticipated annual “Internet Trends” presentation for 2014. All 164 slides are jam-packed with pretty much everything you need to know about the state of the Internet. And as luck would have it, Oracle is staying ahead of these trends (but we’ll talk about that later). There were a few surprises, some stats to solidify what you likely already know, and Meeker’s novel observations about where we are all going. What interested me the most is not only how people are engaging in their personal lives, but how they engage with brands. As you could probably predict, Internet usage growth is slowing while tablet user and mobile data traffic growth continue their meteoric rise around the globe, with tremendous growth in underpenetrated markets like China, India, Brazil and Indonesia. Now hold those the “Internet is dead” comments. Keep in mind there’s still plenty of room to grow, and a multiscreen model is Meeker’s vision for our future. Despite 1.5x YOY growth for mobile traffic, mobile still only makes up about 23% of all traffic today. With tablet shipments easily outpacing figures for PCs even at their height (in 2007), mobile will only continue on it’s path, but won’t be everything to everyone. Mobile won’t replace every touchpoint, it’s just created our shorter attention spans and demand for simpler, more personal experiences. As Meeker points out TVs, tablets, PCs, and smartphones are used for different activities at present, but lines will blur (for example, 84% of smartphones owners use their device while watching TV). Day-to-day activities are being re-imagining through simple, beautiful user experiences. It seems like every day I discover a new way a brand/site/app made the most mundane or mounting task enjoyable and frictionless – and I’m not alone. Meeker points out the evolution of how we do everything from how we communicate, get information, use money, meet someone, get places, order a meal, and consume media is all done through new user interfaces that make day-to-day tasks simpler. This movement has caused just about everyone’s patience for a poor UX to take a nosedive. And it’s not just the digital user experience, technology is making a lot of people’s offline lives easier, and less expensive. Today 47% of online shopping utilizes free shipping— nearly half. And Meeker predicts same day local delivery will be the “next big thing” (and you can take a guess on who will own that). Content, Community and Commerce creates the “Internet Trifecta.” Meeker pointed out that when content, communities and commerce occur in a single experience it’s embraced by consumers, which translates to big dollars for brands. The magic happens when consumers can get inspired, research, and buy in a single experience. As the buying cycle has changed and touchpoints (Web, mobile, social, store) are no longer tied to “roles” or steps in the customer journey, brands must make all experiences (content and commerce) available in a single, adaptable experience. (We at Oracle Commerce have a lot to say on this topic – stay tuned!) And in what Meeker calls the “biggest re-imagination of all:” consumers enabled with smartphones and sensors are creating troves of findable and sharable data, which she says is in the early stages, by growing rapidly. She notes that transparency and patterns of consumers with this hardware (FYI - there are up to 10 sensors embedded in smartphones now) has created a Big Data treasure chest to be mined to improve business and the life of the consumer. The opportunities are endless. So what does it all mean for a company doing business online? Start thinking about how you can: Re-imagine your experience. Not your online experience and your mobile experience and your social experience – your overall experience. When consumers can research, buy, and advocate from anywhere (and their attention spans are at an all-time low) channels don’t exist. Enable simple and beautiful interactions informed by all of the online and offline data you leverage across your enterprise. Ethically leverage the endless supply of data (user generated content, clicks, purchases, in-store behavior, social activity) to make experiences more beautiful, more accurate, and more personalized (not to mention, more lucrative for you). Re-imagine content and commerce. Content and commerce must co-exist in a single destination where shoppers can get inspired, explore, research, share, and purchase in a collective experience. Think of how you can deliver an experience where all types of experiences (brand stories and commerce) adapt to every customer need. (Look for more on this topic coming soon). Re-imagine your reach. Look to Meeker’s findings to see how the global appetite for digital experiences is growing, but under-served in many places (i.e.: India, Mexico, Indonesia, Brazil, Philippines, etc.). Growing your online business to a new geography doesn’t have to mean starting from scratch or having an entirely new team manage the new endeavor. Expand using what you’ve already built in a multisite framework, with global language support. And of course, make sure it’s optimized for mobile! Re-imagine the possible. After every Meeker report, I’m always left with the thought “we are just at the beginning.” Everyday there is more data, more possibilities, more online consumers, and more opportunities to use new latest technology to get closer to your customers and be more successful. There’s a lot going on in our Product Development and Product Innovations groups to automate innovation for our customers, so that they can continue to stay ahead of these trends, without disrupting their business. Check out a recent interview with our Innovations Team on some of these new possibilities. Staying on track despite the seemingly endless possibilities out there is the hard part. Prioritizing where you will focus based on your unique brand promise, customer and goals is what you do best. To learn how Oracle Commerce can help your business achieve your goals check out oracle.com/commerce. Check out Meeker’s entire report here.

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• Maintaining shared service in ASP.NET MVC Application

  - by kazimanzurrashid

  Depending on the application sometimes we have to maintain some shared service throughout our application. Let’s say you are developing a multi-blog supported blog engine where both the controller and view must know the currently visiting blog, it’s setting , user information and url generation service. In this post, I will show you how you can handle this kind of case in most convenient way. First, let see the most basic way, we can create our PostController in the following way: public class PostController : Controller { public PostController(dependencies...) { } public ActionResult Index(string blogName, int? page) { BlogInfo blog = blogSerivce.FindByName(blogName); if (blog == null) { return new NotFoundResult(); } IEnumerable<PostInfo> posts = postService.FindPublished(blog.Id, PagingCalculator.StartIndex(page, blog.PostPerPage), blog.PostPerPage); int count = postService.GetPublishedCount(blog.Id); UserInfo user = null; if (HttpContext.User.Identity.IsAuthenticated) { user = userService.FindByName(HttpContext.User.Identity.Name); } return View(new IndexViewModel(urlResolver, user, blog, posts, count, page)); } public ActionResult Archive(string blogName, int? page, ArchiveDate archiveDate) { BlogInfo blog = blogSerivce.FindByName(blogName); if (blog == null) { return new NotFoundResult(); } IEnumerable<PostInfo> posts = postService.FindArchived(blog.Id, archiveDate, PagingCalculator.StartIndex(page, blog.PostPerPage), blog.PostPerPage); int count = postService.GetArchivedCount(blog.Id, archiveDate); UserInfo user = null; if (HttpContext.User.Identity.IsAuthenticated) { user = userService.FindByName(HttpContext.User.Identity.Name); } return View(new ArchiveViewModel(urlResolver, user, blog, posts, count, page, achiveDate)); } public ActionResult Tag(string blogName, string tagSlug, int? page) { BlogInfo blog = blogSerivce.FindByName(blogName); if (blog == null) { return new NotFoundResult(); } TagInfo tag = tagService.FindBySlug(blog.Id, tagSlug); if (tag == null) { return new NotFoundResult(); } IEnumerable<PostInfo> posts = postService.FindPublishedByTag(blog.Id, tag.Id, PagingCalculator.StartIndex(page, blog.PostPerPage), blog.PostPerPage); int count = postService.GetPublishedCountByTag(tag.Id); UserInfo user = null; if (HttpContext.User.Identity.IsAuthenticated) { user = userService.FindByName(HttpContext.User.Identity.Name); } return View(new TagViewModel(urlResolver, user, blog, posts, count, page, tag)); } } As you can see the above code heavily depends upon the current blog and the blog retrieval code is duplicated in all of the action methods, once the blog is retrieved the same blog is passed in the view model. Other than the blog the view also needs the current user and url resolver to render it properly. One way to remove the duplicate blog retrieval code is to create a custom model binder which converts the blog from a blog name and use the blog a parameter in the action methods instead of the string blog name, but it only helps the first half in the above scenario, the action methods still have to pass the blog, user and url resolver etc in the view model. Now lets try to improve the the above code, first lets create a new class which would contain the shared services, lets name it as BlogContext: public class BlogContext { public BlogInfo Blog { get; set; } public UserInfo User { get; set; } public IUrlResolver UrlResolver { get; set; } } Next, we will create an interface, IContextAwareService: public interface IContextAwareService { BlogContext Context { get; set; } } The idea is, whoever needs these shared services needs to implement this interface, in our case both the controller and the view model, now we will create an action filter which will be responsible for populating the context: public class PopulateBlogContextAttribute : FilterAttribute, IActionFilter { private static string blogNameRouteParameter = "blogName"; private readonly IBlogService blogService; private readonly IUserService userService; private readonly BlogContext context; public PopulateBlogContextAttribute(IBlogService blogService, IUserService userService, IUrlResolver urlResolver) { Invariant.IsNotNull(blogService, "blogService"); Invariant.IsNotNull(userService, "userService"); Invariant.IsNotNull(urlResolver, "urlResolver"); this.blogService = blogService; this.userService = userService; context = new BlogContext { UrlResolver = urlResolver }; } public static string BlogNameRouteParameter { [DebuggerStepThrough] get { return blogNameRouteParameter; } [DebuggerStepThrough] set { blogNameRouteParameter = value; } } public void OnActionExecuting(ActionExecutingContext filterContext) { string blogName = (string) filterContext.Controller.ValueProvider.GetValue(BlogNameRouteParameter).ConvertTo(typeof(string), Culture.Current); if (!string.IsNullOrWhiteSpace(blogName)) { context.Blog = blogService.FindByName(blogName); } if (context.Blog == null) { filterContext.Result = new NotFoundResult(); return; } if (filterContext.HttpContext.User.Identity.IsAuthenticated) { context.User = userService.FindByName(filterContext.HttpContext.User.Identity.Name); } IContextAwareService controller = filterContext.Controller as IContextAwareService; if (controller != null) { controller.Context = context; } } public void OnActionExecuted(ActionExecutedContext filterContext) { Invariant.IsNotNull(filterContext, "filterContext"); if ((filterContext.Exception == null) || filterContext.ExceptionHandled) { IContextAwareService model = filterContext.Controller.ViewData.Model as IContextAwareService; if (model != null) { model.Context = context; } } } } As you can see we are populating the context in the OnActionExecuting, which executes just before the controllers action methods executes, so by the time our action methods executes the context is already populated, next we are are assigning the same context in the view model in OnActionExecuted method which executes just after we set the  model and return the view in our action methods. Now, lets change the view models so that it implements this interface: public class IndexViewModel : IContextAwareService { // More Codes } public class ArchiveViewModel : IContextAwareService { // More Codes } public class TagViewModel : IContextAwareService { // More Codes } and the controller: public class PostController : Controller, IContextAwareService { public PostController(dependencies...) { } public BlogContext Context { get; set; } public ActionResult Index(int? page) { IEnumerable<PostInfo> posts = postService.FindPublished(Context.Blog.Id, PagingCalculator.StartIndex(page, Context.Blog.PostPerPage), Context.Blog.PostPerPage); int count = postService.GetPublishedCount(Context.Blog.Id); return View(new IndexViewModel(posts, count, page)); } public ActionResult Archive(int? page, ArchiveDate archiveDate) { IEnumerable<PostInfo> posts = postService.FindArchived(Context.Blog.Id, archiveDate, PagingCalculator.StartIndex(page, Context.Blog.PostPerPage), Context.Blog.PostPerPage); int count = postService.GetArchivedCount(Context.Blog.Id, archiveDate); return View(new ArchiveViewModel(posts, count, page, achiveDate)); } public ActionResult Tag(string blogName, string tagSlug, int? page) { TagInfo tag = tagService.FindBySlug(Context.Blog.Id, tagSlug); if (tag == null) { return new NotFoundResult(); } IEnumerable<PostInfo> posts = postService.FindPublishedByTag(Context.Blog.Id, tag.Id, PagingCalculator.StartIndex(page, Context.Blog.PostPerPage), Context.Blog.PostPerPage); int count = postService.GetPublishedCountByTag(tag.Id); return View(new TagViewModel(posts, count, page, tag)); } } Now, the last thing where we have to glue everything, I will be using the AspNetMvcExtensibility to register the action filter (as there is no better way to inject the dependencies in action filters). public class RegisterFilters : RegisterFiltersBase { private static readonly Type controllerType = typeof(Controller); private static readonly Type contextAwareType = typeof(IContextAwareService); protected override void Register(IFilterRegistry registry) { TypeCatalog controllers = new TypeCatalogBuilder() .Add(GetType().Assembly) .Include(type => controllerType.IsAssignableFrom(type) && contextAwareType.IsAssignableFrom(type)); registry.Register<PopulateBlogContextAttribute>(controllers); } } Thoughts and Comments?

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• SQLAuthority News – Memories at Anniversary of SQL Wait Stats Book

  - by pinaldave

  SQL Wait Stats About a year ago, I had very proud moment. I had published my second book SQL Server Wait Stats with me as a primary author. It has been a long journey since then. The book got great response and it was widely accepted in the community. It was first of its kind of book written specifically on Wait Stats and Performance. The book was based on my earlier month long series written on the same subject SQL Server Wait Stats. Today, on the anniversary of the book, lots of things come to my mind let me share a few here. Idea behind Blog Series A very common question I often receive is why I wrote a 30 day series on Wait Stats. There were two reasons for it. 1) I have been working with SQL Server for a long time and have troubleshoot more than hundreds of SQL Server which are related to performance tuning. It was a great experience and it taught me a lot of new things. I always documented my experience. After a while I found that I was able to completely rely on my own notes when I was troubleshooting any servers. It is right then I decided to document my experience for the community. 2) While working with wait stats there were a few things, which I thought I knew it well as they were working. However, there was always a fear in the back of mind that what happens if what I believed was incorrect and I was on the wrong path all the time. There was only one way to get it validated. Put it out in front community with my understanding and request further help to improve my understanding. It worked, it worked beautifully. I received plenty of conversations, emails and comments. I refined my content based on various conversations and make it more relevant and near accurate. I guess above two are the major reasons for beginning my journey on writing Wait Stats blog series. Idea behind Book After writing a blog series there was a good amount of request I keep on receiving that I should convert it to eBook or proper book as reading blog posts is great but it goes not give a comprehensive understanding of the subject. The very common feedback from users who were beginning the subject that they will prefer to read it in a structured method. After hearing the feedback for more than 4 months, I decided to write a book based on the blog posts. When I envisioned book, I wanted to make sure this book addresses the wait stats concepts from the fundamentals and fill the gaps of blogs I wrote earlier. Rick Morelan and Joes 2 Pros Team I must acknowledge my co-author Rick Morelan for his unconditional support in writing this book. I had already authored one book before I published this book. The experience to write the book was out of the world. Writing blog posts are much much easier than writing books. The efforts it takes to write a book is 100 times more even though the content is ready. I could have not done it myself if there was not tremendous support of my co-author and editor’s team. We spend days and days researching and discussing various concepts covered in the book. When we were in doubt we reached out to experts as well did a practical reproduction of the scenarios to validate the concepts and claims. After continuous 3 months of hard work we were able to get this book out in the community. September 1st – the lucky day Well, we had to select any day to publish the books. When book was completed in August last week we felt very glad. We all had worked hard and having a sample draft book in hand was feeling like having a newborn baby in our hand. Every time my books are published I feel the same joy which I had when my daughter was born. The feeling of holding a new book in hand is the (almost) same feeling as holding newborn baby. I am excited. For me September 1st has been the luckiest day in mind life. My daughter Shaivi was born on September 1st. Since then every September first has been excellent day and have taken me to the next step in life. I believe anything and everything I do on September 1st it is turning out to be successful and blessed. Rick and I had finished a book in the last week of August. We sent it to the publisher (printer) and asked him to take the book live as soon as possible. We did not decide on any date as we wanted the book to get out as fast as it can. Interesting enough, the publisher/printer selected September 1st for publishing the book. He published the book on 1st September and I knew it at the same time that this book will go next level. Book Model – The Most Beautiful Girl We were done with book. We had no budget left for marketing. Rick and I had a long conversation regarding how to spread the words for the book so it can reach to many people. While we were talking about marketing Rick come up with the idea that we should hire a most beautiful girl around who acknowledge our book and genuinely care for book. It was a difficult task and Rick asked me to find a more beautiful girl. I am a father and the most beautiful girl for me my daughter. This was not a difficult task for me. Rick had given me task to find the most beautiful girl and I just could not think of anyone else than my own daughter. I still do not know what Rick thought about this idea but I had already made up my mind. You can see the detailed blog post here. The Fun Experiments Book Signing Event We had lots of fun moments along this book. We have given away more books to people for free than we have sold them actually. We had done book signing events, contests, and just plain give away when we found people can be benefited from this book. There was never an intention to make money and get rich. We just wanted that more and more people know about this new concept and learn from it. Today when I look back to the earnings there is nothing much we have earned if you talk about dollars. However the best reward which we have received is the satisfaction and love of community. The amount of emails, conversations we have so far received for this book is over thousands. We had fun writing this book, it was indeed a very satisfying journey. I have earned lots of friends while learning and exploring. Availability The book is one year old but still very relevant when it is about performance tuning. It is available at various online book stores. If you have read the book, do let me know what you think of it. Amazon | Kindle | Flipkart | Indiaplaza Reference:  Pinal Dave (http://blog.SQLAuthority.com) Filed under: About Me, Joes 2 Pros, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority, SQLAuthority Book Review, T SQL, Technology

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• Preserving Permalinks

  - by Daniel Moth

  One of the things that gets me on a rant is websites that break permalinks. If you have posted something somewhere and there is a public URL pointing to it, that URL should never ever return a 404. You are breaking all websites that ever linked to you and you are breaking all search engine links to your content (that others will try and follow). It is a pet peeve of mine. So when I had to move my blog, obviously I would preserve the root URL (www.danielmoth.com/Blog/), but I also wanted to preserve every URL my blog has generated over the years. To be clear, our focus here is on the URL formatting, not the content migration which I'll talk about in my next post. In this post, I'll describe my solution first and then what it solves. 1. The IIS7 Rewrite Module and web.config There are a few ways you can map an old URL to a new one (so when requests to the old URL come in, they get redirected to the new one). The new blog engine I use (dasBlog) has built-in functionality to do that (Scott refers to it here). Instead, the way I chose to address the issue was to use the IIS7 rewrite module. The IIS7 rewrite module allows redirecting URLs based on pattern matching, regular expressions and, of course, hardcoded full URLs for things that don't fall into any pattern. You can configure it visually from IIS Manager using a handy dialog that allows testing patterns against input URLs. Here is what mine looked like after configuring a few rules: To learn more about this technology check out this video, the reference page and this overview blog post; all 3 pages have a collection of related resources at the bottom worth checking out too. All the visual configuration ends up in a web.config file at the root folder of your website. If you are on a shared hosting service, probably the only way you can use the Rewrite Module is by directly editing the web.config file. Next, I'll describe the URLs I had to map and how that manifested itself in the web.config file. What I did was create the rules locally using the GUI, and then took the generated web.config file and uploaded it to my live site. You can view my web.config here. 2. Monthly Archives Observe the difference between the way the two blog engines generate this type of URL Blogger: /Blog/2004_07_01_mothblog_archive.html dasBlog: /Blog/default,month,2004-07.aspx In my web.config file, the rule that deals with this is the one named "monthlyarchive_redirect". 3. Categories Observe the difference between the way the two blog engines generate this type of URL Blogger: /Blog/labels/Personal.html dasBlog: /Blog/CategoryView,category,Personal.aspx In my web.config file the rule that deals with this is the one named "category_redirect". 4. Posts Observe the difference between the way the two blog engines generate this type of URL Blogger: /Blog/2004/07/hello-world.html dasBlog: /Blog/Hello-World.aspx In my web.config file the rule that deals with this is the one named "post_redirect". Note: The decision is taken to use dasBlog URLs that do not include the date info (see the description of my Appearance settings). If we included the date info then it would have to include the day part, which blogger did not generate. This makes it impossible to redirect correctly and to have a single permalink for blog posts moving forward. An implication of this decision, is that no two blog posts can have the same title. The tool I will describe in my next post (inelegantly) deals with duplicates, but not with triplicates or higher. 5. Unhandled by a generic rule Unfortunately, the two blog engines use different rules for generating URLs for blog posts. Most of the time the conversion is as simple as the example of the previous section where a post titled "Hello World" generates a URL with the words separated by a hyphen. Some times that is not the case, for example: /Blog/2006/05/medc-wrap-up.html /Blog/MEDC-Wrapup.aspx or /Blog/2005/01/best-of-moth-2004.html /Blog/Best-Of-The-Moth-2004.aspx or /Blog/2004/11/more-windows-mobile-2005-details.html /Blog/More-Windows-Mobile-2005-Details-Emerge.aspx In short, blogger does not add words to the title beyond ~39 characters, it drops some words from the title generation (e.g. a, an, on, the), and it preserve hyphens that appear in the title. For this reason, we need to detect these and explicitly list them for redirects (no regular expression can help here because the full set of rules is not listed anywhere). In my web.config file the rule that deals with this is the one named "Redirect rule1 for FullRedirects" combined with the rewriteMap named "StaticRedirects". Note: The tool I describe in my next post will detect all the URLs that need to be explicitly redirected and will list them in a file ready for you to copy them to your web.config rewriteMap. 6. C# code doing the same as the web.config I wrote some naive code that does the same thing as the web.config: given a string it will return a new string converted according to the 3 rules above. It does not take into account the 4th case where an explicit hard-coded conversion is needed (the tool I present in the next post does take that into account). static string REGEX_post_redirect = "[0-9]{4}/[0-9]{2}/([0-9a-z-]+).html"; static string REGEX_category_redirect = "labels/([_0-9a-z-% ]+).html"; static string REGEX_monthlyarchive_redirect = "([0-9]{4})_([0-9]{2})_[0-9]{2}_mothblog_archive.html"; static string Redirect(string oldUrl) { GroupCollection g; if (RunRegExOnIt(oldUrl, REGEX_post_redirect, 2, out g)) return string.Concat(g[1].Value, ".aspx"); if (RunRegExOnIt(oldUrl, REGEX_category_redirect, 2, out g)) return string.Concat("CategoryView,category,", g[1].Value, ".aspx"); if (RunRegExOnIt(oldUrl, REGEX_monthlyarchive_redirect, 3, out g)) return string.Concat("default,month,", g[1].Value, "-", g[2], ".aspx"); return string.Empty; } static bool RunRegExOnIt(string toRegEx, string pattern, int groupCount, out GroupCollection g) { if (pattern.Length == 0) { g = null; return false; } g = new Regex(pattern, RegexOptions.IgnoreCase | RegexOptions.Compiled).Match(toRegEx).Groups; return (g.Count == groupCount); } Comments about this post welcome at the original blog.

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• Code Contracts: Hiding ContractException

  - by DigiMortal

  It’s time to move on and improve my randomizer I wrote for an example of static checking of code contracts. In this posting I will modify contracts and give some explanations about pre-conditions and post-conditions. Also I will show you how to avoid ContractExceptions and how to replace them with your own exceptions. As a first thing let’s take a look at my randomizer. public class Randomizer {     public static int GetRandomFromRange(int min, int max)     {         var rnd = new Random();         return rnd.Next(min, max);     }       public static int GetRandomFromRangeContracted(int min, int max)     {         Contract.Requires(min < max, "Min must be less than max");           var rnd = new Random();         return rnd.Next(min, max);     } } We have some problems here. We need contract for method output and we also need some better exception handling mechanism. As ContractException as type is hidden from us we have to switch from ContractException to some other Exception type that we can catch. Adding post-condition Pre-conditions are contracts for method’s input interface. Read it as follows: pre-conditions make sure that all conditions for method’s successful run are met. Post-conditions are contracts for output interface of method. So, post-conditions are for output arguments and return value. My code misses the post-condition that checks return value. Return value in this case must be greater or equal to minimum value and less or equal to maximum value. To make sure that method can run only the correct value I added call to Contract.Ensures() method. public static int GetRandomFromRangeContracted(int min, int max) {     Contract.Requires(min < max, "Min must be less than max");       Contract.Ensures(         Contract.Result<int>() >= min &&         Contract.Result<int>() <= max,         "Return value is out of range"     );       var rnd = new Random();     return rnd.Next(min, max); } I think that the line I added does not need any further comments. Avoiding ContractException for input interface ContractException lives in hidden namespace and we cannot see it at design time. But it is common exception type for all contract exceptions that we do not switch over to some other type. The case of Contract.Requires() method is simple: we can tell it what kind of exception we need if something goes wrong with contract it ensures. public static int GetRandomFromRangeContracted(int min, int max) {     Contract.Requires<ArgumentOutOfRangeException>(         min < max,         "Min must be less than max"     );       Contract.Ensures(         Contract.Result<int>() >= min &&         Contract.Result<int>() <= max,         "Return value is out of range"     );       var rnd = new Random();     return rnd.Next(min, max); } Now, if we violate the input interface contract giving min value that is not less than max value we get ArgumentOutOfRangeException. Avoiding ContractException for output interface Output interface is more complex to control. We cannot give exception type there and hope that this type of exception will be thrown if something goes wrong. Instead we have to use delegate that gathers information about problem and throws the exception we expect to be thrown. From documentation you can find the following example about the delegate I mentioned. Contract.ContractFailed += (sender, e) => {     e.SetHandled();     e.SetUnwind(); // cause code to abort after event     Assert.Fail(e.FailureKind.ToString() + ":" + e.DebugMessage); }; We can use this delegate to throw the Exception. Let’s move the code to separate method too. Here is our method that uses now ContractException hiding. public static int GetRandomFromRangeContracted(int min, int max) {     Contract.Requires(min < max, "Min must be less than max");       Contract.Ensures(         Contract.Result<int>() >= min &&         Contract.Result<int>() <= max,         "Return value is out of range"     );     Contract.ContractFailed += Contract_ContractFailed;       var rnd = new Random();     return rnd.Next(min, max)+1000; } And here is the delegate that creates exception. public static void Contract_ContractFailed(object sender,     ContractFailedEventArgs e) {     e.SetHandled();     e.SetUnwind();       throw new Exception(e.FailureKind.ToString() + ":" + e.Message); } Basically we can do in this delegate whatever we like to do with output interface errors. We can even introduce our own contract exception type. As you can see later then ContractFailed event is very useful at unit testing.

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• Adaptive ADF/WebCenter template for the iPad

  - by Maiko Rocha

  One of my WebCenter Portal customers was asking about adaptive design with ADF/WebCenter Portal and how they could go about creating an adaptive iPad template for their WebCenter Portal application. They were looking not only for the out-of-the-box support for mobile Safari which is certified against PS5+ (11.1.1.6) for ADF/WebCenter - but also to create a specific template to streamline their workflow on the iPad. Seems like they wanted something in the lines of Yahoo! Mail provides for the iPad - so the example I will use is shamelessly inspired by Y! Mail's iPad UI.  But first, let's quickly understand how can we bake in some adaptive goodness into ADF Faces. First thing we need to understand is, yes, there are a couple of constraints that we will need to work around, namely, the use or layout managers and skins. Please also keep in mind that I'm not and I don't pretend to be a web designer, much less an UX specialist, so feel free to leave your thoughts on the matter in the comments section. Now, back to the limitations. Layout Managers ADF Faces layout managers create an abstraction on top of the generated HTML code for a page so a developer doesn't need to be worried about how to size and dimension the UI layout (eg, af:panelStretchLayout). Although layout managers are very helpful, in this specific situation we will need to know a little bit more of how the final HTML is being rendered so we can apply the CSS class accordingly and create transition containers where the media queries will be applied - now, if you're using 11gR2 (11.1.2.2.3) there's the new component af:panelGridLayout (here and here) that will greatly improve creating responsive templates and pages because it is based on the grid/fluid systems and will generate straight out to DIVs on your final page. For now, I'm limited to PS5 and the af:panelStretchLayout component as a starting point because that's the release my customer is on. Skins You won't be able to use media queries, or use anything with "@" notation on the skin CSS file - the skin pre-processor will remove all extraneous "@" from the CSS file. The solution is to split your CSS in two separate files: a skin CSS file and plain CSS where you will add the media queries. The issue here is that you won't be able to use media queries for any faces components. We can, though, still apply the media queries for the components like af:panelGroupLayout and af:panelBorderLayout through their styleClass property to enable these components to be responsive to to the iPad orientation, by changing its dimensions, font sizes, hide/show areas, etc. Difference between responsive and adaptive design The best definition of adaptive vs responsive web design I could find is this: “Responsive web design,” as coined by Ethan Marcotte, means “fluid grids, fluid images/media & media queries.” “Adaptive web design,” as I use it, is about creating interfaces that adapt to the user’s capabilities (in terms of both form and function). To me, “adaptive web design” is just another term for “progressive enhancement” of which responsive web design can (an often should) be an integral part, but is a more holistic approach to web design in that it also takes into account varying levels of markup, CSS, JavaScript and assistive technology support. Responsive/adapative web design is much more than slapping an HTML template with CSS around your content or application. The content and application themselves are part of your web design - in other words, a responsive template is just an afterthought if it is not originating from a responsive design the involves the whole web application/s. Tips on responsive / adapative design with ADF/WebCenter Some of the tips listed below were already mentioned in multiple blog posts about ADF layout and skinning, but it is still worth remembering: a simple guideline for ADF/WebCenter apps would be to first create a high-level group of devices, for example: smartphones, tablets,  and desktop. For each of these large groups, create the basic structure to provide responsiveness: a page template, a skin, and an external CSS: pagetemplate_smartphone.jspx, smartphone_skin.css, smartphone-responsive.css pagetemplate_tablet.jspx, tablet_skin.css, tablet-responsive.css pagetemplate_desktop.jspx, desktop_skin.css, desktop-responsive.css These three assets can be changed on the fly through an user-agent check on the server side, delivering the right UI to the right device. Within each of the assets, you can make fine adjustments for each subgroup of devices with media queries - for example, smart phones with different screen dimensions and pixel density. Having these three groups and the corresponding assets per group seem to be a good compromise between trying to put everything on a single set of assets - specially considering the constraints above - and going to the other side of the spectrum to create assets per discrete device (iPhone4, iPhone5, Nexus, S3, etc.). Keep in mind that these are my rules and are not in any shape or form a best practice - this is how it fits best for the scenarios I've been working with. If you need to use HTML tags on your page, surround them with af:group to protect the DOM structure For stretchable/fluid layouts: Use non-stretching containers: panelGroupLayout, panelBorderLayout, … panelBorderLayout can be used to approximate HTML table component To avoid multiple scroll bars, do not nest scrolling PanelGroupLayout components. Consider layout="vertical" For stretchable/fluid layouts: Most stretchable ADF components also work in flowing context with dimensionsFrom="auto" To stretch a component horizontally, use styleClass="AFStretchWidth" instead of  "width:100%" Skinning Don't use CSS3 @media, @import, animations, etc. on skin css files. They will be removed. CSS3 properties within a class (box-shadow, transition, etc.) work just fine. Consider resetting some skin classes to better control their rendering: body {color: inherit;font: inherit;} af|document {-tr-inhibit: all;} af|commandLink {-tr-inhibit: all;} af|goLink {-tr-inhibit: all;} af|inputText::content {font: inherit;} Specific meta tags and CSS properties: Use  <meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0"/> to avoid zooming (if you want) Use -webkit-overflow-scrolling: touch to enable native momentum scrolling within overflown areas (here) Use text-rendering: optmizeLegibility to improve readability. (here) User text-overflow: ellipsis to gracefully crop overflown text. (here) The meta-tags are included in each and every page in the metaContainer facet of af:document tag. You can also use a javascript to inject the meta-tags from the template. For the purpose of the example, I wanted to use as few workarounds as possible.   The iPad template and sample application This sample application has been built as a WebCenter Portal application, but you will also be able to reuse the template and techniques on your vanilla ADF application. Keep in mind that I'm neither a designer nor a CSS specialist, so please don't bash me too much on the messy CSS file you'll find on the application.  I've extended the provided PreferencesBean class that comes with WebCenter Portal and added code to dinamically change the template and skin on the fly.   This is the sample application in landscape orientation: This is the sample application in portrait orientation - the left side menu hides automatically based on a CSS media query: Another screenshot with a skinned popup opened: This is a sample application for you to play with - ideally you shouldn't use it as a starting point. On the left side bar you will find links rendered from a WebCenter Portal navigation model - the link triggers a full request through an af:goLink, while the light blue PPR button triggers a PPR navigation. The dark blue toolbar buttons at the top don't have any function,while the Approve and Reject buttons show a skinned popup. The search box of course doesn't have any behavior attahed to it either. There's a known issue right now with some PPR calls that are randomly generating a 403 error redirecting to the login page - I didn't have time to investigate if this is iOS6 specific or not - if you have any insights please let me know your findings. You can download the sample here.

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• You are probably NOT a SharePoint Development Expert if&hellip;

  - by Mark Rackley

  So, all you aspiring SharePoint experts out there (especially those of you who put “expert” in your resumes).  It’s time for a cold cool splash of reality. More than likely you are NOT an expert (I know I’m not). Yes, you may have some expertise in certain aspects in SharePoint (it’s questionable if I have THAT some days), but make sure you’ve got the basics down before you start throwing that word “expert” around. I know that it becomes frustrating to those looking to hire SharePoint people and having to sift through all the resumes of those who think very highly of themselves and their skills only to find those gaping holes in common best practices. I’m much more willing to hire a decent dev who KNOWS they are not an expert than to hire a decent+ dev who THINKS they are an expert.  So… I’ve compiled a small reality check for you SharePoint Devs. and a “red flag” check for those of you wishing to hire a SharePoint developer. If any of these apply to you, you are probably not a SharePoint Development Expert. You are not a SharePoint Development Expert if you manually copy your DLLs Seriously, I don’t care if you write the best code in the world. If you are manually copying files to each web front end you are NOT a SharePoint Development expert. Yes, I realize the admins are generally the ones who do the actual deployments, but if you don’t know how to create solution packages for your admins, you are going to end up doing more damage than good some day. There are TONS of tools out there to help generate deployable solutions for you. You have ZERO excuse. You are not a SharePoint Development expert if you can’t tell me the main artifacts of a solution package Directly related to the first one. If you don’t know what the Manifest, DDF, WSP, and Feature files are and how they are used in a solution package, you are NOT a SharePoint development expert. I’m not asking you to be able to write them all from scratch (heck, I can’t even do that), but you MUST know what they are and how to tweak them if necessary. You are not a SharePoint Development expert if you don’t know what a Content Type or a Site Column is You would be absolutely amazed at how many “Expert” SharePoint Developers have NEVER EVER created a Content Type or Site Column or even know what they are. I mean, why would you ever want to create those when you can just do everything as a custom list or custom field? right???? (that’s sarcasm). You also need to know how to package a Content Type and a Site Column into a deployable package by the way. You are not a SharePoint Development expert if you have not created at least one Web Part, Workflow, Timer Job, and Event Handler. If you haven’t written at least one of each, you don’t fully understand what they do or their limitations. Again, I expect NO ONE to be able to write these things blind. I think the last time I wrote an application from scratch without copying and pasting from another project I had done before was back in 1994? Seriously, coding is like a Sour Dough starter, you get it from someone else and keep adding to it. You are not a SharePoint Development expert if you don’t know how to properly dispose of objects Another biggie with zero excuse for getting it wrong. It is so well known that you must dispose of your SPWeb and SPSite objects that if you aren’t doing it then you are not an expert. Heck, if you utilize “using” when handling SPWeb and SPSite objects and don’t realize that it disposes of those objects for you, then you are not a SharePoint Development expert. You are not a SharePoint Development expert if you do not know how to properly elevate privileges Just one of those development basics that any decent SharePoint Developer has got to have down and understand how and why it’s used You are not a SharePoint Development expert if you don’t know all of the development options available to SharePoint and when they should be used Okay… so all you hard core .NET SharePoint dev geeks take a moment to listen. You may be the most top not SharePoint .NET developer in the world, but if you are opening Visual Studio to solve every problem in SharePoint, then you are NOT a SharePoint development expert. The SharePoint developer’s tool kit is growing every day with tools like Visual Studio, Data View Web Parts, XSL, jQuery, SPServices, etc. etc… If you don’t have the ability to at least recognize that “hey, you can basically do the same thing here but just dropping in Easy Tabs instead of writing some weird web part” then you are NOT a SharePoint Development expert AND you are doing a huge disservice to your clients and customers. You are probably NOT a SharePoint Development expert if you call yourself an Expert So, truth telling time. I’m not an expert. There, I said it. I feel so much better. Now, I realize the word “expert” has been used with my name before, but I am quick to point out that I KNOW the experts and know that they will help me if I need it, but I’m not an expert in all things SharePoint. The minute you take on that moniker you are setting yourself up for a fall. It’s too big, there’s too much to know, and there’s WAY too much you can do wrong. You are not a SharePoint Development expert if you are not involved in the community I expect to get the most flack for this one, but it’s always a huge red flag for me when someone says they are an expert and has ZERO knowledge of the SharePoint community. The SharePoint community is ABSOLUTELY CRITICAL to be an effective SharePoint developer, admin, architect, power user or whatever the heck you are!! The community keeps you sane, tells you when you are NOT using a best practice, recommends the best practice, and even knows when Microsoft is giving you the wrong information (*gasp* it does happen). If you can’t tell me who you are following on twitter, who's blog you read, what conferences you attend, or name the experts who you monitor to make sure you are not doing something stupid, then you are probably doing something stupid. Again, not asking you to be a speaker, blogger, or the least bit extroverted but you should be at LEAST stalking the experts. So… what’s the point? So… yeah… what’s my point in all this. Well, first of all let me point out that this is by far not a finished list and I could come up with a LOT more specific “deep dive” questions, but these should be high enough level that even non experts can recognize and ask them. If you have some common ones you run into let me know and add them in the comments below. Also, keep in mind I’m not saying you as a developer HAVE to know EVERYTHING, but you DO need to know what you don’t know and proudly and honestly state “I don’t know, but I’ll learn and find out”.  Those of us hiring SharePoint developers and know and have a passion for SharePoint are not looking for that elusive “expert” who knows everything. We are looking for someone who “gets it”, has a similar passion, great attitude, an understanding that they DON’T know everything, and a desire to do it right.  I would bet money that most SharePoint development disasters happen because of “experts” who think they know everything rather than the developer who is cautious and knows he doesn’t. Lastly, I know there’s a raging debate over what a “SharePoint Developer” is (I should know, as I keep bringing it up). So, obviously this blog post is more closely tied to the .NET side of SharePoint development and less towards the client side, middle tier, or whatever you want to call it. So, let’s please not get that argument going here as well…  Thanks

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• Big Data&rsquo;s Killer App&hellip;

  - by jean-pierre.dijcks

  Recently Keith spent  some time talking about the cloud on this blog and I will spare you my thoughts on the whole thing. What I do want to write down is something about the Big Data movement and what I think is the killer app for Big Data... Where is this coming from, ok, I confess... I spent 3 days in cloud land at the Cloud Connect conference in Santa Clara and it was quite a lot of fun. One of the nice things at Cloud Connect was that there was a track dedicated to Big Data, which prompted me to some extend to write this post. What is Big Data anyways? The most valuable point made in the Big Data track was that Big Data in itself is not very cool. Doing something with Big Data is what makes all of this cool and interesting to a business user! The other good insight I got was that a lot of people think Big Data means a single gigantic monolithic system holding gazillions of bytes or documents or log files. Well turns out that most people in the Big Data track are talking about a lot of collections of smaller data sets. So rather than thinking "big = monolithic" you should be thinking "big = many data sets". This is more than just theoretical, it is actually relevant when thinking about big data and how to process it. It is important because it means that the platform that stores data will most likely consist out of multiple solutions. You may be storing logs on something like HDFS, you may store your customer information in Oracle and you may store distilled clickstream information in some distilled form in MySQL. The big question you will need to solve is not what lives where, but how to get it all together and get some value out of all that data. NoSQL and MapReduce Nope, sorry, this is not the killer app... and no I'm not saying this because my business card says Oracle and I'm therefore biased. I think language is important, but as with storage I think pragmatic is better. In other words, some questions can be answered with SQL very efficiently, others can be answered with PERL or TCL others with MR. History should teach us that anyone trying to solve a problem will use any and all tools around. For example, most data warehouses (Big Data 1.0?) get a lot of data in flat files. Everyone then runs a bunch of shell scripts to massage or verify those files and then shoves those files into the database. We've even built shell script support into external tables to allow for this. I think the Big Data projects will do the same. Some people will use MapReduce, although I would argue that things like Cascading are more interesting, some people will use Java. Some data is stored on HDFS making Cascading the way to go, some data is stored in Oracle and SQL does do a good job there. As with storage and with history, be pragmatic and use what fits and neither NoSQL nor MR will be the one and only. Also, a language, while important, does in itself not deliver business value. So while cool it is not a killer app... Vertical Behavioral Analytics This is the killer app! And you are now thinking: "what does that mean?" Let's decompose that heading. First of all, analytics. I would think you had guessed by now that this is really what I'm after, and of course you are right. But not just analytics, which has a very large scope and means many things to many people. I'm not just after Business Intelligence (analytics 1.0?) or data mining (analytics 2.0?) but I'm after something more interesting that you can only do after collecting large volumes of specific data. That all important data is about behavior. What do my customers do? More importantly why do they behave like that? If you can figure that out, you can tailor web sites, stores, products etc. to that behavior and figure out how to be successful. Today's behavior that is somewhat easily tracked is web site clicks, search patterns and all of those things that a web site or web server tracks. that is where the Big Data lives and where these patters are now emerging. Other examples however are emerging, and one of the examples used at the conference was about prediction churn for a telco based on the social network its members are a part of. That social network is not about LinkedIn or Facebook, but about who calls whom. I call you a lot, you switch provider, and I might/will switch too. And that just naturally brings me to the next word, vertical. Vertical in this context means per industry, e.g. communications or retail or government or any other vertical. The reason for being more specific than just behavioral analytics is that each industry has its own data sources, has its own quirky logic and has its own demands and priorities. Of course, the methods and some of the software will be common and some will have both retail and service industry analytics in place (your corner coffee store for example). But the gist of it all is that analytics that can predict customer behavior for a specific focused group of people in a specific industry is what makes Big Data interesting. Building a Vertical Behavioral Analysis System Well, that is going to be interesting. I have not seen much going on in that space and if I had to have some criticism on the cloud connect conference it would be the lack of concrete user cases on big data. The telco example, while a step into the vertical behavioral part is not really on big data. It used a sample of data from the customers' data warehouse. One thing I do think, and this is where I think parts of the NoSQL stuff come from, is that we will be doing this analysis where the data is. Over the past 10 years we at Oracle have called this in-database analytics. I guess we were (too) early? Now the entire market is going there including companies like SAS. In-place btw does not mean "no data movement at all", what it means that you will do this on data's permanent home. For SAS that is kind of the current problem. Most of the inputs live in a data warehouse. So why move it into SAS and back? That all worked with 1 TB data warehouses, but when we are looking at 100TB to 500 TB of distilled data... Comments? As it is still early days with these systems, I'm very interested in seeing reactions and thoughts to some of these thoughts...

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• 202 blog articles

  - by mprove

  All my blog articles under blogs.oracle.com since August 2005: 202 blog articles Apr 2012 blogs.oracle.com design patch Mar 2012 Interaction 12 - Critique Mar 2012 Typing. Clicking. Dancing. Feb 2012 Desktop Mobility in Hospitals with Oracle VDI /video Feb 2012 Interaction 12 in Dublin - Highlights of Day 3 Feb 2012 Interaction 12 in Dublin - Highlights of Day 2 Feb 2012 Interaction 12 in Dublin - Highlights of Day 1 Feb 2012 Shit Interaction Designers Say Feb 2012 Tips'n'Tricks for WebCenter #3: How to display custom page titles in Spaces Jan 2012 Tips'n'Tricks for WebCenter #2: How to create an Admin menu in Spaces and save a lot of time Jan 2012 Tips'n'Tricks for WebCenter #1: How to apply custom resources in Spaces Jan 2012 Merry XMas and a Happy 2012! Dec 2011 One Year Oracle SocialChat - The Movie Nov 2011 Frank Ludolph's Last Working Day Nov 2011 Hans Rosling at TED Oct 2011 200 Countries x 200 Years Oct 2011 Blog Aggregation for Desktop Virtualization Oct 2011 Oracle VDI at OOW 2011 Sep 2011 Design for Conversations & Conversations for Design Sep 2011 All Oracle UX Blogs Aug 2011 Farewell Loriot Aug 2011 Oracle VDI 3.3 Overview Aug 2011 Sutherland's Closing Remarks at HyperKult Aug 2011 Surface and Subface Aug 2011 Back to Childhood in UI Design Jul 2011 The Art of Engineering and The Engineering of Art Jul 2011 Oracle VDI Seminar - June-30 Jun 2011 SGD White Paper May 2011 TEDxHamburg Live Feed May 2011 Oracle VDI in 3 Minutes May 2011 Space Ship Earth 2011 May 2011 blog moving times Apr 2011 Frozen tag cloud Apr 2011 Oracle: Hardware Software Complete in 1953 Apr 2011 Interaction Design with Wireframes Apr 2011 A guide to closing down a project Feb 2011 Oracle VDI 3.2.2 Jan 2011 free VDI charts Jan 2011 Sun Founders Panel 2006 Dec 2010 Sutherland on Leadership Dec 2010 SocialChat: Efficiency of E20 Dec 2010 ALWAYS ON Desktop Virtualization Nov 2010 12,000 Desktops at JavaOne Nov 2010 SocialChat on Sharing Best Practices Oct 2010 Globe of Visitors Oct 2010 SocialChat about the Next Big Thing Oct 2010 Oracle VDI UX Story - Wireframes Oct 2010 What's a PC anyway? Oct 2010 SocialChat on Getting Things Done Oct 2010 SocialChat on Infoglut Oct 2010 IT Twenty Twenty Oct 2010 Desktop Virtualization Webcasts from OOW Oct 2010 Oracle VDI 3.2 Overview Sep 2010 Blog Usability Top 7 Sep 2010 100 and counting Aug 2010 Oracle'izing the VDI Blogs Aug 2010 SocialChat on Apple Aug 2010 SocialChat on Video Conferencing Aug 2010 Oracle VDI 3.2 - Features and Screenshots Aug 2010 SocialChat: Don't stop making waves Aug 2010 SocialChat: Giving Back to the Community Aug 2010 SocialChat on Learning in Meetings Aug 2010 iPAD's Natural User Interface Jul 2010 Last day for Sun Microsystems GmbH Jun 2010 SirValUse Celebration Snippets Jun 2010 10 years SirValUse - Happy Birthday! Jun 2010 Wim on Virtualization May 2010 New Home for Oracle VDI Apr 2010 Renaissance Slide Sorter Comments Apr 2010 Unboxing Sun Ray 3 Plus Apr 2010 Desktop Virtualisierung mit Sun VDI 3.1 Apr 2010 Blog Relaunch Mar 2010 Social Messaging Slides from CeBIT Mar 2010 Social Messaging Talk at CeBIT Feb 2010 Welcome Oracle Jan 2010 My last presentation at Sun Jan 2010 Ivan Sutherland on Leadership Jan 2010 Learning French with Sun VDI Jan 2010 Learning Danish with Sun Ray Jan 2010 VDI workshop in Nieuwegein Jan 2010 Happy New Year 2010 Jan 2010 On Creating Slides Dec 2009 Best VDI Ever Nov 2009 How to store the Big Bang Nov 2009 Social Enterprise Tools. Beipiel Sun. Nov 2009 Nov-19 Nov 2009 PDF and ODF links on your blog Nov 2009 Q&A on VDI and MySQL Cluster Nov 2009 Zürich next week: Swiss Intranet Summit 09 Nov 2009 Designing for a Sustainable World - World Usabiltiy Day, Nov-12 Nov 2009 How to export a desktop from VDI 3 Nov 2009 Virtualisation Roadshow in the UK Nov 2009 Project Wonderland at EDUCAUSE 09 Nov 2009 VDI Roadshow in Dublin, Nov-26, 2009 Nov 2009 Sun VDI at EDUCAUSE 09 Nov 2009 Sun VDI 3.1 Architecture and New Features Oct 2009 VDI 3.1 is Early-Access Sep 2009 Virtualization for MySQL on VMware Sep 2009 Silpion & 13. Stock Sommerparty Sep 2009 Sun Ray and VMware View 3.1.1 2009-08-31 New Set of Sun Ray Status Icons 2009-08-25 Virtualizing the VDI Core? 2009-08-23 World Usability Day Hamburg 2009 - CfP 2009-07-16 Rising Sun 2009-07-15 featuring twittermeme 2009-06-19 ISC09 Student Party on June-20 /Hamburg 2009-06-18 Before and behind the curtain of JavaOne 2009-06-09 20k desktops at JavaOne 2009-06-01 sweet microblogging 2009-05-25 VDI 3 - Why you need 3 VDI hosts and what you can do about that? 2009-05-21 IA Konferenz 2009 2009-05-20 Sun VDI 3 UX Story - Power of the Web 2009-05-06 Planet of Sun and Oracle User Experience Design 2009-04-22 Sun VDI 3 UX Story - User Research 2009-04-08 Sun VDI 3 UX Story - Concept Workshops 2009-04-06 Localized documentation for Sun Ray Connector for VMware View Manager 1.1 2009-04-03 Sun VDI 3 Press Release 2009-03-25 Sun VDI 3 launches today! 2009-03-25 Sun Ray Connector for VMware View Manager 1.1 Update 2009-03-11 desktop virtualization wiki relaunch 2009-03-06 VDI 3 at CeBIT hall 6, booth E36 2009-03-02 Keyboard layout problems with Sun Ray Connector for VMware VDM 2009-02-23 wikis.sun.com tips & tricks 2009-02-23 Sun VDI 3 is in Early Access 2009-02-09 VirtualCenter unable to decrypt passwords 2009-02-02 Sun & VMware Desktop Training 2009-01-30 VDI at next09? 2009-01-16 Sun VDI: How to use virtual machines with multiple network adapters 2009-01-07 Sun Ray and VMware View 2009-01-07 Hamburg World Usability Day 2008 - Webcasts 2009-01-06 Sun Ray Connector for VMware VDM slides 2008-12-15 mother of all demos 2008-12-08 Build your own Thumper 2008-12-03 Troubleshooting Sun Ray Connector for VMware VDM 2008-12-02 My Roller Tag Cloud 2008-11-28 Sun Ray Connector: SSL connection to VDM 2008-11-25 Setting up SSL and Sun Ray Connector for VMware VDM 2008-11-13 Inspiration for Today and Tomorrow 2008-10-23 Sun Ray Connector for VMware VDM released 2008-10-14 From Sketchpad to ILoveSketch 2008-10-09 Desktop Virtualization on Xing 2008-10-06 User Experience Forum on Xing 2008-10-06 Sun Ray Connector for VMware VDM certified 2008-09-17 Virtual Clouds over Las Vegas 2008-09-14 Bill Verplank sketches metaphors 2008-09-04 End of Early Access - Sun Ray Connector for VMware 2008-08-27 Early Access: Sun Ray Connector for VMware Virtual Desktop Manager 2008-08-12 Sun Virtual Desktop Connector - Insides on Recycling Part 2 2008-07-20 Sun Virtual Desktop Connector - Insides on Recycling Part 3 2008-07-20 Sun Virtual Desktop Connector - Insides on Recycling 2008-07-20 lost in wiki space 2008-07-07 Evolution of the Desktop 2008-06-17 Virtual Desktop Webcast 2008-06-16 Woodstock 2008-06-16 What's a Desktop PC anyway? 2008-06-09 Virtual-T-Box 2008-06-05 Virtualization Glossary 2008-05-06 Five User Experience Principles 2008-04-25 Virtualization News Feed 2008-04-21 Acetylcholinesterase - Second Season 2008-04-18 Acetylcholinesterase - End of Signal 2007-12-31 Produkt-Management ist... 2007-10-22 Usability Verbände, Verteiler und Netzwerke. 2007-10-02 The Meaning is the Message 2007-09-28 Visualization Methods 2007-09-10 Inhouse und Open Source Projekte – Usability verankern und Synergien nutzen 2007-09-03 Der Schwabe Darth Vader entdeckt das Virale Marketing 2007-08-29 Dick Hardt 3.0 on Identity 2.0 2007-08-27 quality of written text depends on the tool 2007-07-27 podcasts for reboot9 2007-06-04 It is the user's itch that need to be scratched 2007-05-25 A duel at reboot9 2007-05-14 Taxonomien und Folksonomien - Tagging als neues HCI-Element 2007-05-10 Dueling Interaction Models of Personal-Computing and Web-Computing 2007-03-01 22.März: Weizenbaum. Rebel at Work. /Filmpremiere Hamburg 2007-02-25 Bruce Sterling at UbiComp 2006 /webcast 2006-11-12 FSOSS 2006 /webcasts 2006-11-10 Highway 101 2006-11-09 User Experience Roundtable Hamburg: EuroGEL 2006 2006-11-08 Douglas Adams' Hyperland (BBC 1990) 2006-10-08 Taxonomien und Folksonomien – Tagging als neues HCI-Element 2006-09-13 Usability im Unternehmen 2006-09-13 Doug does HyperScope 2006-08-26 TED Talks and TechTalks 2006-08-21 Kai Krause über seine Freundschaft zu Douglas Adams 2006-07-20 Rebel At Work: Film Portrait on Weizenbaum 2006-07-04 Gabriele Fischer, mp3 2006-06-07 Dick Hardt at ETech 06 2006-06-05 Weinberger: From Control to Conversation 2006-04-16 Eye Tracking at User Experience Roundtable Hamburg 2006-04-14 dropping knowledge 2006-04-09 GEL 2005 2006-03-13 slide photos of reboot7 2006-03-04 Dick Hardt on Identity 2.0 2006-02-28 User Experience Newsletter #13: Versioning 2006-02-03 Ester Dyson on Choice and Happyness 2006-02-02 Requirements-Engineering im Spannungsfeld von Individual- und Produktsoftware 2006-01-15 User Experience Newsletter #12: Intuition Quiz 2005-11-30 User Experience und Requirements-Engineering für Software-Projekte 2005-10-31 Ivan Sutherland on "Research and Fun" 2005-10-18 Ars Electronica / Mensch und Computer 2005 2005-09-14 60 Jahre nach Memex: Über die Unvereinbarkeit von Desktop- und Web-Paradigma 2005-08-31 reboot 7 2005-06-30

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• What's up with LDoms: Part 4 - Virtual Networking Explained

  - by Stefan Hinker

  I'm back from my summer break (and some pressing business that kept me away from this), ready to continue with Oracle VM Server for SPARC ;-) In this article, we'll have a closer look at virtual networking.  Basic connectivity as we've seen it in the first, simple example, is easy enough.  But there are numerous options for the virtual switches and virtual network ports, which we will discuss in more detail now.   In this section, we will concentrate on virtual networking - the capabilities of virtual switches and virtual network ports - only.  Other options involving hardware assignment or redundancy will be covered in separate sections later on. There are two basic components involved in virtual networking for LDoms: Virtual switches and virtual network devices.  The virtual switch should be seen just like a real ethernet switch.  It "runs" in the service domain and moves ethernet packets back and forth.  A virtual network device is plumbed in the guest domain.  It corresponds to a physical network device in the real world.  There, you'd be plugging a cable into the network port, and plug the other end of that cable into a switch.  In the virtual world, you do the same:  You create a virtual network device for your guest and connect it to a virtual switch in a service domain.  The result works just like in the physical world, the network device sends and receives ethernet packets, and the switch does all those things ethernet switches tend to do. If you look at the reference manual of Oracle VM Server for SPARC, there are numerous options for virtual switches and network devices.  Don't be confused, it's rather straight forward, really.  Let's start with the simple case, and work our way to some more sophisticated options later on.  In many cases, you'll want to have several guests that communicate with the outside world on the same ethernet segment.  In the real world, you'd connect each of these systems to the same ethernet switch.  So, let's do the same thing in the virtual world: root@sun # ldm add-vsw net-dev=nxge2 admin-vsw primary root@sun # ldm add-vnet admin-net admin-vsw mars root@sun # ldm add-vnet admin-net admin-vsw venus We've just created a virtual switch called "admin-vsw" and connected it to the physical device nxge2.  In the physical world, we'd have powered up our ethernet switch and installed a cable between it and our big enterprise datacenter switch.  We then created a virtual network interface for each one of the two guest systems "mars" and "venus" and connected both to that virtual switch.  They can now communicate with each other and with any system reachable via nxge2.  If primary were running Solaris 10, communication with the guests would not be possible.  This is different with Solaris 11, please see the Admin Guide for details.  Note that I've given both the vswitch and the vnet devices some sensible names, something I always recommend. Unless told otherwise, the LDoms Manager software will automatically assign MAC addresses to all network elements that need one.  It will also make sure that these MAC addresses are unique and reuse MAC addresses to play nice with all those friendly DHCP servers out there.  However, if we want to do this manually, we can also do that.  (One reason might be firewall rules that work on MAC addresses.)  So let's give mars a manually assigned MAC address: root@sun # ldm set-vnet mac-addr=0:14:4f:f9:c4:13 admin-net mars Within the guest, these virtual network devices have their own device driver.  In Solaris 10, they'd appear as "vnet0".  Solaris 11 would apply it's usual vanity naming scheme.  We can configure these interfaces just like any normal interface, give it an IP-address and configure sophisticated routing rules, just like on bare metal.  In many cases, using Jumbo Frames helps increase throughput performance.  By default, these interfaces will run with the standard ethernet MTU of 1500 bytes.  To change this,  it is usually sufficient to set the desired MTU for the virtual switch.  This will automatically set the same MTU for all vnet devices attached to that switch.  Let's change the MTU size of our admin-vsw from the example above: root@sun # ldm set-vsw mtu=9000 admin-vsw primary Note that that you can set the MTU to any value between 1500 and 16000.  Of course, whatever you set needs to be supported by the physical network, too. Another very common area of network configuration is VLAN tagging. This can be a little confusing - my advise here is to be very clear on what you want, and perhaps draw a little diagram the first few times.  As always, keeping a configuration simple will help avoid errors of all kind.  Nevertheless, VLAN tagging is very usefull to consolidate different networks onto one physical cable.  And as such, this concept needs to be carried over into the virtual world.  Enough of the introduction, here's a little diagram to help in explaining how VLANs work in LDoms: Let's remember that any VLANs not explicitly tagged have the default VLAN ID of 1. In this example, we have a vswitch connected to a physical network that carries untagged traffic (VLAN ID 1) as well as VLANs 11, 22, 33 and 44.  There might also be other VLANs on the wire, but the vswitch will ignore all those packets.  We also have two vnet devices, one for mars and one for venus.  Venus will see traffic from VLANs 33 and 44 only.  For VLAN 44, venus will need to configure a tagged interface "vnet44000".  For VLAN 33, the vswitch will untag all incoming traffic for venus, so that venus will see this as "normal" or untagged ethernet traffic.  This is very useful to simplify guest configuration and also allows venus to perform Jumpstart or AI installations over this network even if the Jumpstart or AI server is connected via VLAN 33.  Mars, on the other hand, has full access to untagged traffic from the outside world, and also to VLANs 11,22 and 33, but not 44.  On the command line, we'd do this like this: root@sun # ldm add-vsw net-dev=nxge2 pvid=1 vid=11,22,33,44 admin-vsw primary root@sun # ldm add-vnet admin-net pvid=1 vid=11,22,33 admin-vsw mars root@sun # ldm add-vnet admin-net pvid=33 vid=44 admin-vsw venus Finally, I'd like to point to a neat little option that will make your live easier in all those cases where configurations tend to change over the live of a guest system.  It's the "id=<somenumber>" option available for both vswitches and vnet devices.  Normally, Solaris in the guest would enumerate network devices sequentially.  However, it has ways of remembering this initial numbering.  This is good in the physical world.  In the virtual world, whenever you unbind (aka power off and disassemble) a guest system, remove and/or add network devices and bind the system again, chances are this numbering will change.  Configuration confusion will follow suit.  To avoid this, nail down the initial numbering by assigning each vnet device it's device-id explicitly: root@sun # ldm add-vnet admin-net id=1 admin-vsw venus Please consult the Admin Guide for details on this, and how to decipher these network ids from Solaris running in the guest. Thanks for reading this far.  Links for further reading are essentially only the Admin Guide and Reference Manual and can be found above.  I hope this is useful and, as always, I welcome any comments.

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• How to get SQL Railroad Diagrams from MSDN BNF syntax notation.

  - by Phil Factor

  pre {margin-bottom:.0001pt; font-size:8.0pt; font-family:"Courier New"; margin-left: 0cm; margin-right: 0cm; margin-top: 0cm; } On SQL Server Books-On-Line, in the Transact-SQL Reference (database Engine), every SQL Statement has its syntax represented in  ‘Backus–Naur Form’ notation (BNF)  syntax. For a programmer in a hurry, this should be ideal because It is the only quick way to understand and appreciate all the permutations of the syntax. It is a great feature once you get your eye in. It isn’t the only way to get the information;  You can, of course, reverse-engineer an understanding of the syntax from the examples, but your understanding won’t be complete, and you’ll have wasted time doing it. BNF is a good start in representing the syntax:  Oracle and SQLite go one step further, and have proper railroad diagrams for their syntax, which is a far more accessible way of doing it. There are three problems with the BNF on MSDN. Firstly, it is isn’t a standard version of  BNF, but an ancient fork from EBNF, inherited from Sybase. Secondly, it is excruciatingly difficult to understand, and thirdly it has a number of syntactic and semantic errors. The page describing DML triggers, for example, currently has the absurd BNF error that makes it state that all statements in the body of the trigger must be separated by commas.  There are a few other detail problems too. Here is the offending syntax for a DML trigger, pasted from MSDN. Trigger on an INSERT, UPDATE, or DELETE statement to a table or view (DML Trigger) CREATE TRIGGER [ schema_name . ]trigger_name ON { table | view } [ WITH <dml_trigger_option> [ ,...n ] ] { FOR | AFTER | INSTEAD OF } { [ INSERT ] [ , ] [ UPDATE ] [ , ] [ DELETE ] } [ NOT FOR REPLICATION ] AS { sql_statement [ ; ] [ ,...n ] | EXTERNAL NAME <method specifier [ ; ] > }   <dml_trigger_option> ::=     [ ENCRYPTION ]     [ EXECUTE AS Clause ]   <method_specifier> ::=  This should, of course, be /* Trigger on an INSERT, UPDATE, or DELETE statement to a table or view (DML Trigger) */ CREATE TRIGGER [ schema_name . ]trigger_name ON { table | view } [ WITH <dml_trigger_option> [ ,...n ] ] { FOR | AFTER | INSTEAD OF } { [ INSERT ] [ , ] [ UPDATE ] [ , ] [ DELETE ] } [ NOT FOR REPLICATION ] AS { {sql_statement [ ; ]} [ ...n ] | EXTERNAL NAME <method_specifier> [ ; ] }   <dml_trigger_option> ::=     [ ENCRYPTION ]     [ EXECUTE AS CLAUSE ]   <method_specifier> ::=     assembly_name.class_name.method_name I’d love to tell Microsoft when I spot errors like this so they can correct them but I can’t. Obviously, there is a mechanism on MSDN to get errors corrected by using comments, but that doesn’t work for me (*Error occurred while saving your data.”), and when I report that the comment system doesn’t work to MSDN, I get no reply. I’ve been trying to create railroad diagrams for all the important SQL Server SQL statements, as good as you’d find for Oracle, and have so far published the CREATE TABLE and ALTER TABLE railroad diagrams based on the BNF. Although I’ve been aware of them, I’ve never realised until recently how many errors there are. Then, Colin Daley created a translator for the SQL Server dialect of  BNF which outputs standard EBNF notation used by the W3C. The example MSDN BNF for the trigger would be rendered as … /* Trigger on an INSERT, UPDATE, or DELETE statement to a table or view (DML Trigger) */ create_trigger ::= 'CREATE TRIGGER' ( schema_name '.' ) ? trigger_name 'ON' ( table | view ) ( 'WITH' dml_trigger_option ( ',' dml_trigger_option ) * ) ? ( 'FOR' | 'AFTER' | 'INSTEAD OF' ) ( ( 'INSERT' ) ? ( ',' ) ? ( 'UPDATE' ) ? ( ',' ) ? ( 'DELETE' ) ? ) ( 'NOT FOR REPLICATION' ) ? 'AS' ( ( sql_statement ( ';' ) ? ) + | 'EXTERNAL NAME' method_specifier ( ';' ) ? )   dml_trigger_option ::= ( 'ENCRYPTION' ) ? ( 'EXECUTE AS CLAUSE' ) ?   method_specifier ::= assembly_name '.' class_name '.' method_name Colin’s intention was to allow anyone to paste SQL Server’s BNF notation into his website-based parser, and from this generate classic railroad diagrams via Gunther Rademacher's Railroad Diagram Generator.  Colin's application does this for you: you're not aware that you are moving to a different site.  Because Colin's 'translator' it is a parser, it will pick up syntax errors. Once you’ve fixed the syntax errors, you will get the syntax in the form of a human-readable railroad diagram and, in this form, the semantic mistakes become flamingly obvious. Gunter’s Railroad Diagram Generator is brilliant. To be able, after correcting the MSDN dialect of BNF, to generate a standard EBNF, and from thence to create railroad diagrams for SQL Server’s syntax that are as good as Oracle’s, is a great boon, and many thanks to Colin for the idea. Here is the result of the W3C EBNF from Colin’s application then being run through the Railroad diagram generator. create_trigger: dml_trigger_option: method_specifier:   Now that’s much better, you’ll agree. This is pretty easy to understand, and at this point any error is immediately obvious. This should be seriously useful, and it is to me. However  there is that snag. The BNF is generally incorrect, and you can’t expect the average visitor to mess about with it. The answer is, of course, to correct the BNF on MSDN and maybe even add railroad diagrams for the syntax. Stop giggling! I agree it won’t happen. In the meantime, we need to collaboratively store and publish these corrected syntaxes ourselves as we do them. How? GitHub?  SQL Server Central?  Simple-Talk? What should those of us who use the system  do with our corrected EBNF so that anyone can use them without hassle?

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• Listing common SQL Code Smells.

  - by Phil Factor

  Once you’ve done a number of SQL Code-reviews, you’ll know those signs in the code that all might not be well. These ’Code Smells’ are coding styles that don’t directly cause a bug, but are indicators that all is not well with the code. . Kent Beck and Massimo Arnoldi seem to have coined the phrase in the "OnceAndOnlyOnce" page of www.C2.com, where Kent also said that code "wants to be simple". Bad Smells in Code was an essay by Kent Beck and Martin Fowler, published as Chapter 3 of the book ‘Refactoring: Improving the Design of Existing Code’ (ISBN 978-0201485677) Although there are generic code-smells, SQL has its own particular coding habits that will alert the programmer to the need to re-factor what has been written. See Exploring Smelly Code   and Code Deodorants for Code Smells by Nick Harrison for a grounding in Code Smells in C# I’ve always been tempted by the idea of automating a preliminary code-review for SQL. It would be so useful to trawl through code and pick up the various problems, much like the classic ‘Lint’ did for C, and how the Code Metrics plug-in for .NET Reflector by Jonathan 'Peli' de Halleux is used for finding Code Smells in .NET code. The problem is that few of the standard procedural code smells are relevant to SQL, and we need an agreed list of code smells. Merrilll Aldrich made a grand start last year in his blog Top 10 T-SQL Code Smells.However, I'd like to make a start by discovering if there is a general opinion amongst Database developers what the most important SQL Smells are. One can be a bit defensive about code smells. I will cheerfully write very long stored procedures, even though they are frowned on. I’ll use dynamic SQL occasionally. You can only use them as an aid for your own judgment and it is fine to ‘sign them off’ as being appropriate in particular circumstances. Also, whole classes of ‘code smells’ may be irrelevant for a particular database. The use of proprietary SQL, for example, is only a ‘code smell’ if there is a chance that the database will have to be ported to another RDBMS. The use of dynamic SQL is a risk only with certain security models. As the saying goes,  a CodeSmell is a hint of possible bad practice to a pragmatist, but a sure sign of bad practice to a purist. Plamen Ratchev’s wonderful article Ten Common SQL Programming Mistakes lists some of these ‘code smells’ along with out-and-out mistakes, but there are more. The use of nested transactions, for example, isn’t entirely incorrect, even though the database engine ignores all but the outermost: but it does flag up the possibility that the programmer thinks that nested transactions are supported. If anything requires some sort of general agreement, the definition of code smells is one. I’m therefore going to make this Blog ‘dynamic, in that, if anyone twitters a suggestion with a #SQLCodeSmells tag (or sends me a twitter) I’ll update the list here. If you add a comment to the blog with a suggestion of what should be added or removed, I’ll do my best to oblige. In other words, I’ll try to keep this blog up to date. The name against each 'smell' is the name of the person who Twittered me, commented about or who has written about the 'smell'. it does not imply that they were the first ever to think of the smell! Use of deprecated syntax such as *= (Dave Howard) Denormalisation that requires the shredding of the contents of columns. (Merrill Aldrich) Contrived interfaces Use of deprecated datatypes such as TEXT/NTEXT (Dave Howard) Datatype mis-matches in predicates that rely on implicit conversion.(Plamen Ratchev) Using Correlated subqueries instead of a join   (Dave_Levy/ Plamen Ratchev) The use of Hints in queries, especially NOLOCK (Dave Howard /Mike Reigler) Few or No comments. Use of functions in a WHERE clause. (Anil Das) Overuse of scalar UDFs (Dave Howard, Plamen Ratchev) Excessive ‘overloading’ of routines. The use of Exec xp_cmdShell (Merrill Aldrich) Excessive use of brackets. (Dave Levy) Lack of the use of a semicolon to terminate statements Use of non-SARGable functions on indexed columns in predicates (Plamen Ratchev) Duplicated code, or strikingly similar code. Misuse of SELECT * (Plamen Ratchev) Overuse of Cursors (Everyone. Special mention to Dave Levy & Adrian Hills) Overuse of CLR routines when not necessary (Sam Stange) Same column name in different tables with different datatypes. (Ian Stirk) Use of ‘broken’ functions such as ‘ISNUMERIC’ without additional checks. Excessive use of the WHILE loop (Merrill Aldrich) INSERT ... EXEC (Merrill Aldrich) The use of stored procedures where a view is sufficient (Merrill Aldrich) Not using two-part object names (Merrill Aldrich) Using INSERT INTO without specifying the columns and their order (Merrill Aldrich) Full outer joins even when they are not needed. (Plamen Ratchev) Huge stored procedures (hundreds/thousands of lines). Stored procedures that can produce different columns, or order of columns in their results, depending on the inputs. Code that is never used. Complex and nested conditionals WHILE (not done) loops without an error exit. Variable name same as the Datatype Vague identifiers. Storing complex data  or list in a character map, bitmap or XML field User procedures with sp_ prefix (Aaron Bertrand)Views that reference views that reference views that reference views (Aaron Bertrand) Inappropriate use of sql_variant (Neil Hambly) Errors with identity scope using SCOPE_IDENTITY @@IDENTITY or IDENT_CURRENT (Neil Hambly, Aaron Bertrand) Schemas that involve multiple dated copies of the same table instead of partitions (Matt Whitfield-Atlantis UK) Scalar UDFs that do data lookups (poor man's join) (Matt Whitfield-Atlantis UK) Code that allows SQL Injection (Mladen Prajdic) Tables without clustered indexes (Matt Whitfield-Atlantis UK) Use of "SELECT DISTINCT" to mask a join problem (Nick Harrison) Multiple stored procedures with nearly identical implementation. (Nick Harrison) Excessive column aliasing may point to a problem or it could be a mapping implementation. (Nick Harrison) Joining "too many" tables in a query. (Nick Harrison) Stored procedure returning more than one record set. (Nick Harrison) A NOT LIKE condition (Nick Harrison) excessive "OR" conditions. (Nick Harrison) User procedures with sp_ prefix (Aaron Bertrand) Views that reference views that reference views that reference views (Aaron Bertrand) sp_OACreate or anything related to it (Bill Fellows) Prefixing names with tbl_, vw_, fn_, and usp_ ('tibbling') (Jeremiah Peschka) Aliases that go a,b,c,d,e... (Dave Levy/Diane McNurlan) Overweight Queries (e.g. 4 inner joins, 8 left joins, 4 derived tables, 10 subqueries, 8 clustered GUIDs, 2 UDFs, 6 case statements = 1 query) (Robert L Davis) Order by 3,2 (Dave Levy) MultiStatement Table functions which are then filtered 'Sel * from Udf() where Udf.Col = Something' (Dave Ballantyne) running a SQL 2008 system in SQL 2000 compatibility mode(John Stafford)

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• SQL SERVER – Shrinking Database is Bad – Increases Fragmentation – Reduces Performance

  - by pinaldave

  Earlier, I had written two articles related to Shrinking Database. I wrote about why Shrinking Database is not good. SQL SERVER – SHRINKDATABASE For Every Database in the SQL Server SQL SERVER – What the Business Says Is Not What the Business Wants I received many comments on Why Database Shrinking is bad. Today we will go over a very interesting example that I have created for the same. Here are the quick steps of the example. Create a test database Create two tables and populate with data Check the size of both the tables Size of database is very low Check the Fragmentation of one table Fragmentation will be very low Truncate another table Check the size of the table Check the fragmentation of the one table Fragmentation will be very low SHRINK Database Check the size of the table Check the fragmentation of the one table Fragmentation will be very HIGH REBUILD index on one table Check the size of the table Size of database is very HIGH Check the fragmentation of the one table Fragmentation will be very low Here is the script for the same. USE MASTER GO CREATE DATABASE ShrinkIsBed GO USE ShrinkIsBed GO -- Name of the Database and Size SELECT name, (size*8) Size_KB FROM sys.database_files GO -- Create FirstTable CREATE TABLE FirstTable (ID INT, FirstName VARCHAR(100), LastName VARCHAR(100), City VARCHAR(100)) GO -- Create Clustered Index on ID CREATE CLUSTERED INDEX [IX_FirstTable_ID] ON FirstTable ( [ID] ASC ) ON [PRIMARY] GO -- Create SecondTable CREATE TABLE SecondTable (ID INT, FirstName VARCHAR(100), LastName VARCHAR(100), City VARCHAR(100)) GO -- Create Clustered Index on ID CREATE CLUSTERED INDEX [IX_SecondTable_ID] ON SecondTable ( [ID] ASC ) ON [PRIMARY] GO -- Insert One Hundred Thousand Records INSERT INTO FirstTable (ID,FirstName,LastName,City) SELECT TOP 100000 ROW_NUMBER() OVER (ORDER BY a.name) RowID, 'Bob', CASE WHEN ROW_NUMBER() OVER (ORDER BY a.name)%2 = 1 THEN 'Smith' ELSE 'Brown' END, CASE WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 1 THEN 'New York' WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 5 THEN 'San Marino' WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 3 THEN 'Los Angeles' ELSE 'Houston' END FROM sys.all_objects a CROSS JOIN sys.all_objects b GO -- Name of the Database and Size SELECT name, (size*8) Size_KB FROM sys.database_files GO -- Insert One Hundred Thousand Records INSERT INTO SecondTable (ID,FirstName,LastName,City) SELECT TOP 100000 ROW_NUMBER() OVER (ORDER BY a.name) RowID, 'Bob', CASE WHEN ROW_NUMBER() OVER (ORDER BY a.name)%2 = 1 THEN 'Smith' ELSE 'Brown' END, CASE WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 1 THEN 'New York' WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 5 THEN 'San Marino' WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 3 THEN 'Los Angeles' ELSE 'Houston' END FROM sys.all_objects a CROSS JOIN sys.all_objects b GO -- Name of the Database and Size SELECT name, (size*8) Size_KB FROM sys.database_files GO -- Check Fragmentations in the database SELECT avg_fragmentation_in_percent, fragment_count FROM sys.dm_db_index_physical_stats (DB_ID(), OBJECT_ID('SecondTable'), NULL, NULL, 'LIMITED') GO Let us check the table size and fragmentation. Now let us TRUNCATE the table and check the size and Fragmentation. USE MASTER GO CREATE DATABASE ShrinkIsBed GO USE ShrinkIsBed GO -- Name of the Database and Size SELECT name, (size*8) Size_KB FROM sys.database_files GO -- Create FirstTable CREATE TABLE FirstTable (ID INT, FirstName VARCHAR(100), LastName VARCHAR(100), City VARCHAR(100)) GO -- Create Clustered Index on ID CREATE CLUSTERED INDEX [IX_FirstTable_ID] ON FirstTable ( [ID] ASC ) ON [PRIMARY] GO -- Create SecondTable CREATE TABLE SecondTable (ID INT, FirstName VARCHAR(100), LastName VARCHAR(100), City VARCHAR(100)) GO -- Create Clustered Index on ID CREATE CLUSTERED INDEX [IX_SecondTable_ID] ON SecondTable ( [ID] ASC ) ON [PRIMARY] GO -- Insert One Hundred Thousand Records INSERT INTO FirstTable (ID,FirstName,LastName,City) SELECT TOP 100000 ROW_NUMBER() OVER (ORDER BY a.name) RowID, 'Bob', CASE WHEN ROW_NUMBER() OVER (ORDER BY a.name)%2 = 1 THEN 'Smith' ELSE 'Brown' END, CASE WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 1 THEN 'New York' WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 5 THEN 'San Marino' WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 3 THEN 'Los Angeles' ELSE 'Houston' END FROM sys.all_objects a CROSS JOIN sys.all_objects b GO -- Name of the Database and Size SELECT name, (size*8) Size_KB FROM sys.database_files GO -- Insert One Hundred Thousand Records INSERT INTO SecondTable (ID,FirstName,LastName,City) SELECT TOP 100000 ROW_NUMBER() OVER (ORDER BY a.name) RowID, 'Bob', CASE WHEN ROW_NUMBER() OVER (ORDER BY a.name)%2 = 1 THEN 'Smith' ELSE 'Brown' END, CASE WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 1 THEN 'New York' WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 5 THEN 'San Marino' WHEN ROW_NUMBER() OVER (ORDER BY a.name)%10 = 3 THEN 'Los Angeles' ELSE 'Houston' END FROM sys.all_objects a CROSS JOIN sys.all_objects b GO -- Name of the Database and Size SELECT name, (size*8) Size_KB FROM sys.database_files GO -- Check Fragmentations in the database SELECT avg_fragmentation_in_percent, fragment_count FROM sys.dm_db_index_physical_stats (DB_ID(), OBJECT_ID('SecondTable'), NULL, NULL, 'LIMITED') GO You can clearly see that after TRUNCATE, the size of the database is not reduced and it is still the same as before TRUNCATE operation. After the Shrinking database operation, we were able to reduce the size of the database. If you notice the fragmentation, it is considerably high. The major problem with the Shrink operation is that it increases fragmentation of the database to very high value. Higher fragmentation reduces the performance of the database as reading from that particular table becomes very expensive. One of the ways to reduce the fragmentation is to rebuild index on the database. Let us rebuild the index and observe fragmentation and database size. -- Rebuild Index on FirstTable ALTER INDEX IX_SecondTable_ID ON SecondTable REBUILD GO -- Name of the Database and Size SELECT name, (size*8) Size_KB FROM sys.database_files GO -- Check Fragmentations in the database SELECT avg_fragmentation_in_percent, fragment_count FROM sys.dm_db_index_physical_stats (DB_ID(), OBJECT_ID('SecondTable'), NULL, NULL, 'LIMITED') GO You can notice that after rebuilding, Fragmentation reduces to a very low value (almost same to original value); however the database size increases way higher than the original. Before rebuilding, the size of the database was 5 MB, and after rebuilding, it is around 20 MB. Regular rebuilding the index is rebuild in the same user database where the index is placed. This usually increases the size of the database. Look at irony of the Shrinking database. One person shrinks the database to gain space (thinking it will help performance), which leads to increase in fragmentation (reducing performance). To reduce the fragmentation, one rebuilds index, which leads to size of the database to increase way more than the original size of the database (before shrinking). Well, by Shrinking, one did not gain what he was looking for usually. Rebuild indexing is not the best suggestion as that will create database grow again. I have always remembered the excellent post from Paul Randal regarding Shrinking the database is bad. I suggest every one to read that for accuracy and interesting conversation. Let us run following script where we Shrink the database and REORGANIZE. -- Name of the Database and Size SELECT name, (size*8) Size_KB FROM sys.database_files GO -- Check Fragmentations in the database SELECT avg_fragmentation_in_percent, fragment_count FROM sys.dm_db_index_physical_stats (DB_ID(), OBJECT_ID('SecondTable'), NULL, NULL, 'LIMITED') GO -- Shrink the Database DBCC SHRINKDATABASE (ShrinkIsBed); GO -- Name of the Database and Size SELECT name, (size*8) Size_KB FROM sys.database_files GO -- Check Fragmentations in the database SELECT avg_fragmentation_in_percent, fragment_count FROM sys.dm_db_index_physical_stats (DB_ID(), OBJECT_ID('SecondTable'), NULL, NULL, 'LIMITED') GO -- Rebuild Index on FirstTable ALTER INDEX IX_SecondTable_ID ON SecondTable REORGANIZE GO -- Name of the Database and Size SELECT name, (size*8) Size_KB FROM sys.database_files GO -- Check Fragmentations in the database SELECT avg_fragmentation_in_percent, fragment_count FROM sys.dm_db_index_physical_stats (DB_ID(), OBJECT_ID('SecondTable'), NULL, NULL, 'LIMITED') GO You can see that REORGANIZE does not increase the size of the database or remove the fragmentation. Again, I no way suggest that REORGANIZE is the solution over here. This is purely observation using demo. Read the blog post of Paul Randal. Following script will clean up the database -- Clean up USE MASTER GO ALTER DATABASE ShrinkIsBed SET SINGLE_USER WITH ROLLBACK IMMEDIATE GO DROP DATABASE ShrinkIsBed GO There are few valid cases of the Shrinking database as well, but that is not covered in this blog post. We will cover that area some other time in future. Additionally, one can rebuild index in the tempdb as well, and we will also talk about the same in future. Brent has written a good summary blog post as well. Are you Shrinking your database? Well, when are you going to stop Shrinking it? Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Index, SQL Performance, SQL Query, SQL Scripts, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology

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• SQL SERVER – Extending SQL Azure with Azure worker role – Guest Post by Paras Doshi

  - by pinaldave

  This is guest post by Paras Doshi. Paras Doshi is a research Intern at SolidQ.com and a Microsoft student partner. He is currently working in the domain of SQL Azure. SQL Azure is nothing but a SQL server in the cloud. SQL Azure provides benefits such as on demand rapid provisioning, cost-effective scalability, high availability and reduced management overhead. To see an introduction on SQL Azure, check out the post by Pinal here In this article, we are going to discuss how to extend SQL Azure with the Azure worker role. In other words, we will attempt to write a custom code and host it in the Azure worker role; the aim is to add some features that are not available with SQL Azure currently or features that need to be customized for flexibility. This way we extend the SQL Azure capability by building some solutions that run on Azure as worker roles. To understand Azure worker role, think of it as a windows service in cloud. Azure worker role can perform background processes, and to handle processes such as synchronization and backup, it becomes our ideal tool. First, we will focus on writing a worker role code that synchronizes SQL Azure databases. Before we do so, let’s see some scenarios in which synchronization between SQL Azure databases is beneficial: scaling out access over multiple databases enables us to handle workload efficiently As of now, SQL Azure database can be hosted in one of any six datacenters. By synchronizing databases located in different data centers, one can extend the data by enabling access to geographically distributed data Let us see some scenarios in which SQL server to SQL Azure database synchronization is beneficial To backup SQL Azure database on local infrastructure Rather than investing in local infrastructure for increased workloads, such workloads could be handled by cloud Ability to extend data to different datacenters located across the world to enable efficient data access from remote locations Now, let us develop cloud-based app that synchronizes SQL Azure databases. For an Introduction to developing cloud based apps, click here Now, in this article, I aim to provide a bird’s eye view of how a code that synchronizes SQL Azure databases look like and then list resources that can help you develop the solution from scratch. Now, if you newly add a worker role to the cloud-based project, this is how the code will look like. (Note: I have added comments to the skeleton code to point out the modifications that will be required in the code to carry out the SQL Azure synchronization. Note the placement of Setup() and Sync() function.) Click here (http://parasdoshi1989.files.wordpress.com/2011/06/code-snippet-1-for-extending-sql-azure-with-azure-worker-role1.pdf ) Enabling SQL Azure databases synchronization through sync framework is a two-step process. In the first step, the database is provisioned and sync framework creates tracking tables, stored procedures, triggers, and tables to store metadata to enable synchronization. This is one time step. The code for the same is put in the setup() function which is called once when the worker role starts. Now, the second step is continuous (or on demand) synchronization of SQL Azure databases by propagating changes between databases. This is done on a continuous basis by calling the sync() function in the while loop. The code logic to synchronize changes between SQL Azure databases should be put in the sync() function. Discussing the coding part step by step is out of the scope of this article. Therefore, let me suggest you a resource, which is given here. Also, note that before you start developing the code, you will need to install SYNC framework 2.1 SDK (download here). Further, you will reference some libraries before you start coding. Details regarding the same are available in the article that I just pointed to. You will be charged for data transfers if the databases are not in the same datacenter. For pricing information, go here Currently, a tool named DATA SYNC, which is built on top of sync framework, is available in CTP that allows SQL Azure <-> SQL server and SQL Azure <-> SQL Azure synchronization (without writing single line of code); however, in some cases, the custom code shown in this blogpost provides flexibility that is not available with Data SYNC. For instance, filtering is not supported in the SQL Azure DATA SYNC CTP2; if you wish to have such a functionality now, then you have the option of developing a custom code using SYNC Framework. Now, this code can be easily extended to synchronize at some schedule. Let us say we want the databases to get synchronized every day at 10:00 pm. This is what the code will look like now: (http://parasdoshi1989.files.wordpress.com/2011/06/code-snippet-2-for-extending-sql-azure-with-azure-worker-role.pdf) Don’t you think that by writing such a code, we are imitating the functionality provided by the SQL server agent for a SQL server? Think about it. We are scheduling our administrative task by writing custom code – in other words, we have developed a “Light weight SQL server agent for SQL Azure!” Since the SQL server agent is not currently available in cloud, we have developed a solution that enables us to schedule tasks, and thus we have extended SQL Azure with the Azure worker role! Now if you wish to track jobs, you can do so by storing this data in SQL Azure (or Azure tables). The reason is that Windows Azure is a stateless platform, and we will need to store the state of the job ourselves and the choice that you have is SQL Azure or Azure tables. Note that this solution requires custom code and also it is not UI driven; however, for now, it can act as a temporary solution until SQL server agent is made available in the cloud. Moreover, this solution does not encompass functionalities that a SQL server agent provides, but it does open up an interesting avenue to schedule some of the tasks such as backup and synchronization of SQL Azure databases by writing some custom code in the Azure worker role. Now, let us see one more possibility – i.e., running BCP through a worker role in Azure-hosted services and then uploading the backup files either locally or on blobs. If you upload it locally, then consider the data transfer cost. If you upload it to blobs residing in the same datacenter, then no transfer cost applies but the cost on blob size applies. So, before choosing the option, you need to evaluate your preferences keeping the cost associated with each option in mind. In this article, I have shown that Azure worker role solution could be developed to synchronize SQL Azure databases. Moreover, a light-weight SQL server agent for SQL Azure can be developed. Also we discussed the possibility of running BCP through a worker role in Azure-hosted services for backing up our precious SQL Azure data. Thus, we can extend SQL Azure with the Azure worker role. But remember: you will be charged for running Azure worker roles. So at the end of the day, you need to ask – am I willing to build a custom code and pay money to achieve this functionality? I hope you found this blog post interesting. If you have any questions/feedback, you can comment below or you can mail me at Paras[at]student-partners[dot]com Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, SQL, SQL Authority, SQL Azure, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• CodePlex Daily Summary for Friday, September 07, 2012

  CodePlex Daily Summary for Friday, September 07, 2012Popular ReleasesUmbraco CMS: Umbraco 4.9.0: Whats newThe media section has been overhauled to support HTML5 uploads, just drag and drop files in, even multiple files are supported on any HTML5 capable browser. The folder content overview is also much improved allowing you to filter it and perform common actions on your media items. The Rich Text Editor’s “Media” button now uses an embedder based on the open oEmbed standard (if you’re upgrading, enable the media button in the Rich Text Editor datatype settings and set TidyEditorConten...menu4web: menu4web 0.4.1 - javascript menu for web sites: This release is for those who believe that global variables are evil. menu4web has been wrapped into m4w singleton object. Added "Vertical Tabs" example which illustrates object notation.WinRT XAML Toolkit: WinRT XAML Toolkit - 1.2.1: WinRT XAML Toolkit based on the Windows 8 RTM SDK. Download the latest source from the SOURCE CODE page. For compiled version use NuGet. You can add it to your project in Visual Studio by going to View/Other Windows/Package Manager Console and entering: PM> Install-Package winrtxamltoolkit Features AsyncUI extensions Controls and control extensions Converters Debugging helpers Imaging IO helpers VisualTree helpers Samples Recent changes NOTE: Namespace changes DebugConsol...iPDC - Free Phasor Data Concentrator: iPDC-v1.3.1: iPDC suite version-1.3.1, Modifications and Bug Fixed (from v 1.3.0) New User Manual for iPDC-v1.3.1 available on websites. Bug resolved : PMU Simulator TCP connection error and hang connection for client (PDC). Now PMU Simulator (server) can communicate more than one PDCs (clients) over TCP and UDP parallely. PMU Simulator is now sending the exact data frames as mentioned in data rate by user. PMU Simulator data rate has been verified by iPDC database entries and PMU Connection Tes...Microsoft SQL Server Product Samples: Database: AdventureWorks OData Feed: The AdventureWorks OData service exposes resources based on specific SQL views. The SQL views are a limited subset of the AdventureWorks database that results in several consuming scenarios: CompanySales Documents ManufacturingInstructions ProductCatalog TerritorySalesDrilldown WorkOrderRouting How to install the sample You can consume the AdventureWorks OData feed from http://services.odata.org/AdventureWorksV3/AdventureWorks.svc. You can also consume the AdventureWorks OData fe...Desktop Google Reader: 1.4.6: Sorting feeds alphabetical is now optional (see preferences window)DotNetNuke® Community Edition CMS: 06.02.03: Major Highlights Fixed issue where mailto: links were not working when sending bulk email Fixed issue where uses did not see friendship relationships Problem is in 6.2, which does not show in the Versions Affected list above. Fixed the issue with cascade deletes in comments in CoreMessaging_Notification Fixed UI issue when using a date fields as a required profile property during user registration Fixed error when running the product in debug mode Fixed visibility issue when...Microsoft Ajax Minifier: Microsoft Ajax Minifier 4.65: Fixed null-reference error in the build task constructor.B INI Sharp Library: B INI Sharp Library v1.0.0.0 Final Realsed: The frist realsedActive Social Migrator: ActiveSocialMigrator 1.0.0 Beta: Beta release for the Active Social Migration tool.EntLib.com????????: ??????demo??-For SQL 2005-2008: EntLibShopping ???v3.0 - ??????demo??，?????SQL SERVER 2005/2008/2008 R2/2012 ??????。 ??（??）??????。 THANKS.Sistem LPK Pemkot Semarang: Panduan Penggunaan Sistem LPK: Panduan cara menggunakan Aplikasi Sistem LPK Bagian Pembangunan Kota SemarangActive Forums for DotNetNuke CMS: Active Forums 5.0.0 RC: RC release of Active Forums 5.0.Droid Explorer: Droid Explorer 0.8.8.7 Beta: Bug in the display icon for apk's, will fix with next release Added fallback icon if unable to get the image/icon from the Cloud Service Removed some stale plugins that were either out dated or incomplete. Added handler for *.ab files for restoring backups Added plugin to create device backups Backups stored in %USERPROFILE%\Android Backups\%DEVICE_ID%\ Added custom folder icon for the android backups directory better error handling for installing an apk bug fixes for the Runn...The Visual Guide for Building Team Foundation Server 2012 Environments: Version 1: --Nearforums - ASP.NET MVC forum engine: Nearforums v8.5: Version 8.5 of Nearforums, the ASP.NET MVC Forum Engine. New features include: Built-in search engine using Lucene.NET Flood control improvements Notifications improvements: sync option and mail body View Roadmap for more details webdeploy package sha1 checksum: 961aff884a9187b6e8a86d68913cdd31f8deaf83WiX Toolset: WiX Toolset v3.6: WiX Toolset v3.6 introduces the Burn bootstrapper/chaining engine and support for Visual Studio 2012 and .NET Framework 4.5. Other minor functionality includes: WixDependencyExtension supports dependency checking among MSI packages. WixFirewallExtension supports more features of Windows Firewall. WixTagExtension supports Software Id Tagging. WixUtilExtension now supports recursive directory deletion. Melt simplifies pure-WiX patching by extracting .msi package content and updating .w...Iveely Search Engine: Iveely Search Engine （0.2.0）: ????ISE?0.1.0??，?????，ISE?0.2.0?????????，???????，????????20???follow?ISE，????，??ISE??????????，??????????，?????????，?????????0.2.0??????，??????????。 Iveely Search Engine ?0.2.0?????????“??????????”，??????，?????????，???????，???????????????????，????、????????????。???0.1.0????????????： 1. ??“????” ??。??????????，?????????，???????????????????。??：????????，????????????，??????????????????。??????。 2. ??“????”??。?0.1.0??????，???????，???????????????，?????????????，????????，?0.2.0?，???????...GmailDefaultMaker: GmailDefaultMaker 3.0.0.2: Add QQ Mail BugfixSmart Data Access layer: Smart Data access Layer Ver 3: In this version support executing inline query is added. Check Documentation section for detail.New ProjectsAdding 2013 Jewish Holidays for Outlook2003: Instruction: Copy the outlook.hol file to your compuer where Outlook2003 is installed. Double click the file, choose "Israel" and continue. That's it Agilcont System: Sistema de contabilidad para empresas privadas de preferencia para cajas que trabajan con efectivo en soles, dolares y con el material oroARB (A Request Broker): The idea is something like a Request Broker, but with some additional functionality.BATTLE.NET - SDK: This SDK provides the ability to use the Battle.net (Blizzard) Services for all supported Games such Diablo 3, World of Warcraft. Container Terminal System: SummaryDeclarative UX Streaming Data Language for the Cloud: Bringing a better communication paradigm for media and data..Get User Profile Information from SharePoint UserProfile Service: Used SharePoint object model to get the user profile information from the User Profile Service.Guess The City & State Windows 8 Source Code: Source code for Guess The City & State in Malaysia Windows 8 AppJquery Tree: This project is to demonstrate tree basic functionality.MCEBuddy 2.x: Convert and Remove Commercials for your Windows Media CenterMvcDesign: MvcDesign engine implementation projectMy Task Manager: This is a task manager module for DotNetNuke. I am using it to get started developing modules.MyAppwithbranches: MyAppwithbranchesProjecte prova: rpyGEO: pyGEO is a python package capable of parsing microarray data files. It also has a primitive plotting function.Scarlet Road: Scarlet Road is a top-down shooter. It's you against an unending horde of monsters.simplecounter: A simple counter, cick and counter.SiteEmpires: ????????Soundcloud Loader: Simple Tool for downloading Tracks from Soundcloud.Windows Phone Samples: Windows Phone code samples.

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• Use Extension method to write cleaner code

  - by Fredrik N

  This blog post will show you step by step to refactoring some code to be more readable (at least what I think). Patrik Löwnedahl gave me some of the ideas when we where talking about making code much cleaner. The following is an simple application that will have a list of movies (Normal and Transfer). The task of the application is to calculate the total sum of each movie and also display the price of each movie. class Program { enum MovieType { Normal, Transfer } static void Main(string[] args) { var movies = GetMovies(); int totalPriceOfNormalMovie = 0; int totalPriceOfTransferMovie = 0; foreach (var movie in movies) { if (movie == MovieType.Normal) { totalPriceOfNormalMovie += 2; Console.WriteLine("$2"); } else if (movie == MovieType.Transfer) { totalPriceOfTransferMovie += 3; Console.WriteLine("$3"); } } } private static IEnumerable<MovieType> GetMovies() { return new List<MovieType>() { MovieType.Normal, MovieType.Transfer, MovieType.Normal }; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } In the code above I’m using an enum, a good way to add types (isn’t it ;)). I also use one foreach loop to calculate the price, the loop has a condition statement to check what kind of movie is added to the list of movies. I want to reuse the foreach only to increase performance and let it do two things (isn’t that smart of me?! ;)). First of all I can admit, I’m not a big fan of enum. Enum often results in ugly condition statements and can be hard to maintain (if a new type is added we need to check all the code in our app to see if we use the enum somewhere else). I don’t often care about pre-optimizations when it comes to write code (of course I have performance in mind). I rather prefer to use two foreach to let them do one things instead of two. So based on what I don’t like and Martin Fowler’s Refactoring catalog, I’m going to refactoring this code to what I will call a more elegant and cleaner code. First of all I’m going to use Split Loop to make sure the foreach will do one thing not two, it will results in two foreach (Don’t care about performance here, if the results will results in bad performance, you can refactoring later, but computers are so fast to day, so iterating through a list is not often so time consuming.) Note: The foreach actually do four things, will come to is later. var movies = GetMovies(); int totalPriceOfNormalMovie = 0; int totalPriceOfTransferMovie = 0; foreach (var movie in movies) { if (movie == MovieType.Normal) { totalPriceOfNormalMovie += 2; Console.WriteLine("$2"); } } foreach (var movie in movies) { if (movie == MovieType.Transfer) { totalPriceOfTransferMovie += 3; Console.WriteLine("$3"); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } To remove the condition statement we can use the Where extension method added to the IEnumerable<T> and is located in the System.Linq namespace: foreach (var movie in movies.Where( m => m == MovieType.Normal)) { totalPriceOfNormalMovie += 2; Console.WriteLine("$2"); } foreach (var movie in movies.Where( m => m == MovieType.Transfer)) { totalPriceOfTransferMovie += 3; Console.WriteLine("$3"); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The above code will still do two things, calculate the total price, and display the price of the movie. I will not take care of it at the moment, instead I will focus on the enum and try to remove them. One way to remove enum is by using the Replace Conditional with Polymorphism. So I will create two classes, one base class called Movie, and one called MovieTransfer. The Movie class will have a property called Price, the Movie will now hold the price:   public class Movie { public virtual int Price { get { return 2; } } } public class MovieTransfer : Movie { public override int Price { get { return 3; } } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The following code has no enum and will use the new Movie classes instead: class Program { static void Main(string[] args) { var movies = GetMovies(); int totalPriceOfNormalMovie = 0; int totalPriceOfTransferMovie = 0; foreach (var movie in movies.Where( m => m is Movie)) { totalPriceOfNormalMovie += movie.Price; Console.WriteLine(movie.Price); } foreach (var movie in movies.Where( m => m is MovieTransfer)) { totalPriceOfTransferMovie += movie.Price; Console.WriteLine(movie.Price); } } private static IEnumerable<Movie> GetMovies() { return new List<Movie>() { new Movie(), new MovieTransfer(), new Movie() }; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   If you take a look at the foreach now, you can see it still actually do two things, calculate the price and display the price. We can do some more refactoring here by using the Sum extension method to calculate the total price of the movies:   static void Main(string[] args) { var movies = GetMovies(); int totalPriceOfNormalMovie = movies.Where(m => m is Movie) .Sum(m => m.Price); int totalPriceOfTransferMovie = movies.Where(m => m is MovieTransfer) .Sum(m => m.Price); foreach (var movie in movies.Where( m => m is Movie)) Console.WriteLine(movie.Price); foreach (var movie in movies.Where( m => m is MovieTransfer)) Console.WriteLine(movie.Price); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Now when the Movie object will hold the price, there is no need to use two separate foreach to display the price of the movies in the list, so we can use only one instead: foreach (var movie in movies) Console.WriteLine(movie.Price); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } If we want to increase the Maintainability index we can use the Extract Method to move the Sum of the prices into two separate methods. The name of the method will explain what we are doing: static void Main(string[] args) { var movies = GetMovies(); int totalPriceOfMovie = TotalPriceOfMovie(movies); int totalPriceOfTransferMovie = TotalPriceOfMovieTransfer(movies); foreach (var movie in movies) Console.WriteLine(movie.Price); } private static int TotalPriceOfMovieTransfer(IEnumerable<Movie> movies) { return movies.Where(m => m is MovieTransfer) .Sum(m => m.Price); } private static int TotalPriceOfMovie(IEnumerable<Movie> movies) { return movies.Where(m => m is Movie) .Sum(m => m.Price); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Now to the last thing, I love the ForEach method of the List<T>, but the IEnumerable<T> doesn’t have it, so I created my own ForEach extension, here is the code of the ForEach extension method: public static class LoopExtensions { public static void ForEach<T>(this IEnumerable<T> values, Action<T> action) { Contract.Requires(values != null); Contract.Requires(action != null); foreach (var v in values) action(v); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } I will now replace the foreach by using this ForEach method: static void Main(string[] args) { var movies = GetMovies(); int totalPriceOfMovie = TotalPriceOfMovie(movies); int totalPriceOfTransferMovie = TotalPriceOfMovieTransfer(movies); movies.ForEach(m => Console.WriteLine(m.Price)); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The ForEach on the movies will now display the price of the movie, but maybe we want to display the name of the movie etc, so we can use Extract Method by moving the lamdba expression into a method instead, and let the method explains what we are displaying: movies.ForEach(DisplayMovieInfo); private static void DisplayMovieInfo(Movie movie) { Console.WriteLine(movie.Price); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Now the refactoring is done! Here is the complete code:   class Program { static void Main(string[] args) { var movies = GetMovies(); int totalPriceOfMovie = TotalPriceOfMovie(movies); int totalPriceOfTransferMovie = TotalPriceOfMovieTransfer(movies); movies.ForEach(DisplayMovieInfo); } private static void DisplayMovieInfo(Movie movie) { Console.WriteLine(movie.Price); } private static int TotalPriceOfMovieTransfer(IEnumerable<Movie> movies) { return movies.Where(m => m is MovieTransfer) .Sum(m => m.Price); } private static int TotalPriceOfMovie(IEnumerable<Movie> movies) { return movies.Where(m => m is Movie) .Sum(m => m.Price); } private static IEnumerable<Movie> GetMovies() { return new List<Movie>() { new Movie(), new MovieTransfer(), new Movie() }; } } public class Movie { public virtual int Price { get { return 2; } } } public class MovieTransfer : Movie { public override int Price { get { return 3; } } } pulbic static class LoopExtensions { public static void ForEach<T>(this IEnumerable<T> values, Action<T> action) { Contract.Requires(values != null); Contract.Requires(action != null); foreach (var v in values) action(v); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } I think the new code is much cleaner than the first one, and I love the ForEach extension on the IEnumerable<T>, I can use it for different kind of things, for example: movies.Where(m => m is Movie) .ForEach(DoSomething); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } By using the Where and ForEach extension method, some if statements can be removed and will make the code much cleaner. But the beauty is in the eye of the beholder. What would you have done different, what do you think will make the first example in the blog post look much cleaner than my results, comments are welcome! If you want to know when I will publish a new blog post, you can follow me on twitter: http://www.twitter.com/fredrikn

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• C#/.NET Little Pitfalls: The Dangers of Casting Boxed Values

  - by James Michael Hare

  Starting a new series to parallel the Little Wonders series.  In this series, I will examine some of the small pitfalls that can occasionally trip up developers. Introduction: Of Casts and Conversions What happens when we try to assign from an int and a double and vice-versa? 1: double pi = 3.14; 2: int theAnswer = 42; 3:  4: // implicit widening conversion, compiles! 5: double doubleAnswer = theAnswer; 6:  7: // implicit narrowing conversion, compiler error! 8: int intPi = pi; As you can see from the comments above, a conversion from a value type where there is no potential data loss is can be done with an implicit conversion.  However, when converting from one value type to another may result in a loss of data, you must make the conversion explicit so the compiler knows you accept this risk.  That is why the conversion from double to int will not compile with an implicit conversion, we can make the conversion explicit by adding a cast: 1: // explicit narrowing conversion using a cast, compiler 2: // succeeds, but results may have data loss: 3: int intPi = (int)pi; So for value types, the conversions (implicit and explicit) both convert the original value to a new value of the given type.  With widening and narrowing references, however, this is not the case.  Converting reference types is a bit different from converting value types.  First of all when you perform a widening or narrowing you don’t really convert the instance of the object, you just convert the reference itself to the wider or narrower reference type, but both the original and new reference type both refer back to the same object. Secondly, widening and narrowing for reference types refers the going down and up the class hierarchy instead of referring to precision as in value types.  That is, a narrowing conversion for a reference type means you are going down the class hierarchy (for example from Shape to Square) whereas a widening conversion means you are going up the class hierarchy (from Square to Shape).  1: var square = new Square(); 2:  3: // implicitly convers because all squares are shapes 4: // (that is, all subclasses can be referenced by a superclass reference) 5: Shape myShape = square; 6:  7: // implicit conversion not possible, not all shapes are squares! 8: // (that is, not all superclasses can be referenced by a subclass reference) 9: Square mySquare = (Square) myShape; So we had to cast the Shape back to Square because at that point the compiler has no way of knowing until runtime whether the Shape in question is truly a Square.  But, because the compiler knows that it’s possible for a Shape to be a Square, it will compile.  However, if the object referenced by myShape is not truly a Square at runtime, you will get an invalid cast exception. Of course, there are other forms of conversions as well such as user-specified conversions and helper class conversions which are beyond the scope of this post.  The main thing we want to focus on is this seemingly innocuous casting method of widening and narrowing conversions that we come to depend on every day and, in some cases, can bite us if we don’t fully understand what is going on!  The Pitfall: Conversions on Boxed Value Types Can Fail What if you saw the following code and – knowing nothing else – you were asked if it was legal or not, what would you think: 1: // assuming x is defined above this and this 2: // assignment is syntactically legal. 3: x = 3.14; 4:  5: // convert 3.14 to int. 6: int truncated = (int)x; You may think that since x is obviously a double (can’t be a float) because 3.14 is a double literal, but this is inaccurate.  Our x could also be dynamic and this would work as well, or there could be user-defined conversions in play.  But there is another, even simpler option that can often bite us: what if x is object? 1: object x; 2:  3: x = 3.14; 4:  5: int truncated = (int) x; On the surface, this seems fine.  We have a double and we place it into an object which can be done implicitly through boxing (no cast) because all types inherit from object.  Then we cast it to int.  This theoretically should be possible because we know we can explicitly convert a double to an int through a conversion process which involves truncation. But here’s the pitfall: when casting an object to another type, we are casting a reference type, not a value type!  This means that it will attempt to see at runtime if the value boxed and referred to by x is of type int or derived from type int.  Since it obviously isn’t (it’s a double after all) we get an invalid cast exception! Now, you may say this looks awfully contrived, but in truth we can run into this a lot if we’re not careful.  Consider using an IDataReader to read from a database, and then attempting to select a result row of a particular column type: 1: using (var connection = new SqlConnection("some connection string")) 2: using (var command = new SqlCommand("select * from employee", connection)) 3: using (var reader = command.ExecuteReader()) 4: { 5: while (reader.Read()) 6: { 7: // if the salary is not an int32 in the SQL database, this is an error! 8: // doesn't matter if short, long, double, float, reader [] returns object! 9: total += (int) reader["annual_salary"]; 10: } 11: } Notice that since the reader indexer returns object, if we attempt to convert using a cast to a type, we have to make darn sure we use the true, actual type or this will fail!  If the SQL database column is a double, float, short, etc this will fail at runtime with an invalid cast exception because it attempts to convert the object reference! So, how do you get around this?  There are two ways, you could first cast the object to its actual type (double), and then do a narrowing cast to on the value to int.  Or you could use a helper class like Convert which analyzes the actual run-time type and will perform a conversion as long as the type implements IConvertible. 1: object x; 2:  3: x = 3.14; 4:  5: // if you want to cast, must cast out of object to double, then 6: // cast convert. 7: int truncated = (int)(double) x; 8:  9: // or you can call a helper class like Convert which examines runtime 10: // type of the value being converted 11: int anotherTruncated = Convert.ToInt32(x); Summary You should always be careful when performing a conversion cast from values boxed in object that you are actually casting to the true type (or a sub-type). Since casting from object is a widening of the reference, be careful that you either know the exact, explicit type you expect to be held in the object, or instead avoid the cast and use a helper class to perform a safe conversion to the type you desire. Technorati Tags: C#,.NET,Pitfalls,Little Pitfalls,BlackRabbitCoder

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• How to Organize a Programming Language Club

  - by Ben Griswold

  I previously noted that we started a language club at work.  You know, I searched around but I couldn’t find a copy of the How to Organize a Programming Language Club Handbook. Maybe it’s sold out?  Yes, Stack Overflow has quite a bit of information on how to learn and teach new languages and there’s also a good number of online tutorials which provide language introductions but I was interested in group learning.  After   two months of meetings, I present to you the Unofficial How to Organize a Programming Language Club Handbook.  1. Gauge interest. Start by surveying prospects. “Excuse me, smart-developer-whom-I-work-with-and-I-think-might-be-interested-in-learning-a-new-coding-language-with-me. Are you interested in learning a new language with me?” If you’re lucky, you work with a bunch of really smart folks who aren’t shy about teaching/learning in a group setting and you’ll have a collective interest in no time.  Simply suggesting the idea is the only effort required.  If you don’t work in this type of environment, maybe you should consider a new place of employment.  2. Make it official. Send out a “Welcome to the Club” email: There’s been talk of folks itching to learn new languages – Python, Scala, F# and Haskell to name a few.  Rather than taking on new languages alone, let’s learn in the open.  That’s right.  Let’s start a languages club.  We’ll have everything a real club needs – secret handshake, goofy motto and a high-and-mighty sense that we’re better than everybody else. T-shirts?  Hell YES!  Anyway, I’ve thrown this idea around the office and no one has laughed at me yet so please consider this your very official invitation to be in THE club. [Insert your ideas about how the club might be run, solicit feedback and suggestions, ask what other folks would like to get out the club, comment about club hazing practices and talk up the T-shirts even more. Finally, call out the languages you are interested in learning and ask the group for their list.] 3.  Send out invitations to the first meeting.  Don’t skimp!  Hallmark greeting cards for everyone.  Personalized.  Hearts over the I’s and everything.  Oh, and be sure to include the list of suggested languages with vote count.  Here the list of languages we are interested in: Python 5 Ruby 4 Objective-C 3 F# 2 Haskell 2 Scala 2 Ada 1 Boo 1 C# 1 Clojure 1 Erlang 1 Go 1 Pi 1 Prolog 1 Qt 1 4.  At the first meeting, there must be cake.  Lots of cake. And you should tackle some very important questions: Which language should we start with?  You can immediately go with the top vote getter or you could do as we did and designate each person to provide a high-level review of each of the proposed languages over the next two weeks.  After all presentations are completed, vote on the language. Our high-level review consisted of answers to a series of questions. Decide how often and where the group will meet.  We, for example, meet for a brown bag lunch every Wednesday.  Decide how you’re going to learn.  We determined that the best way to learn is to just dive in and write code.  After choosing our first language (Python), we talked about building an application, or performing coding katas, but we ultimately choose to complete a series of Project Euler problems.  We kept it simple – each member works out the same two problems each week in preparation of a code review the following Wednesday. 5.  Code, Review, Learn.  Prior to the weekly meeting, everyone uploads their solutions to our internal wiki.  Each Project Euler problem has a dedicated page.  In the meeting, we use a really fancy HD projector to show off each member’s solution.  It is very important to use an HD projector.  Again, don’t skimp!  Each code author speaks to their solution, everyone else comments, applauds, points fingers and laughs, etc.  As much as I’ve learned from solving the problems on my own, I’ve learned at least twice as much at the group code review.  6.  Rinse. Lather. Repeat.  We’ve hosted the language club for 7 weeks now.  The first meeting just set the stage.  The next two meetings provided a review of the languages followed by a first language selection.  The remaining meetings focused on Python and Project Euler problems.  Today we took a vote as to whether or not we’re ready to switch to another language and/or another problem set.  Pretty much everyone wants to stay the course for a few more weeks at least.  Until then, we’ll continue to code the next two solutions, review and learn. Again, we’ve been having a good time with the programming language club.  I’m glad it got off the ground.  What do you think?  Would you be interested in a language club?  Any suggestions on what we might do better?

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• SQL Monitor’s data repository

  - by Chris Lambrou

  As one of the developers of SQL Monitor, I often get requests passed on by our support people from customers who are looking to dip into SQL Monitor’s own data repository, in order to pull out bits of information that they’re interested in. Since there’s clearly interest out there in playing around directly with the data repository, I thought I’d write some blog posts to start to describe how it all works. The hardest part for me is knowing where to begin, since the schema of the data repository is pretty big. Hmmm… I guess it’s tricky for anyone to write anything but the most trivial of queries against the data repository without understanding the hierarchy of monitored objects, so perhaps my first post should start there. I always imagine that whenever a customer fires up SSMS and starts to explore their SQL Monitor data repository database, they become immediately bewildered by the schema – that was certainly my experience when I did so for the first time. The following query shows the number of different object types in the data repository schema: SELECT type_desc, COUNT(*) AS [count] FROM sys.objects GROUP BY type_desc ORDER BY type_desc;  type_desccount 1DEFAULT_CONSTRAINT63 2FOREIGN_KEY_CONSTRAINT181 3INTERNAL_TABLE3 4PRIMARY_KEY_CONSTRAINT190 5SERVICE_QUEUE3 6SQL_INLINE_TABLE_VALUED_FUNCTION381 7SQL_SCALAR_FUNCTION2 8SQL_STORED_PROCEDURE100 9SYSTEM_TABLE41 10UNIQUE_CONSTRAINT54 11USER_TABLE193 12VIEW124 With 193 tables, 124 views, 100 stored procedures and 381 table valued functions, that’s quite a hefty schema, and when you browse through it using SSMS, it can be a bit daunting at first. So, where to begin? Well, let’s narrow things down a bit and only look at the tables belonging to the data schema. That’s where all of the collected monitoring data is stored by SQL Monitor. The following query gives us the names of those tables: SELECT sch.name + '.' + obj.name AS [name] FROM sys.objects obj JOIN sys.schemas sch ON sch.schema_id = obj.schema_id WHERE obj.type_desc = 'USER_TABLE' AND sch.name = 'data' ORDER BY sch.name, obj.name; This query still returns 110 tables. I won’t show them all here, but let’s have a look at the first few of them:  name 1data.Cluster_Keys 2data.Cluster_Machine_ClockSkew_UnstableSamples 3data.Cluster_Machine_Cluster_StableSamples 4data.Cluster_Machine_Keys 5data.Cluster_Machine_LogicalDisk_Capacity_StableSamples 6data.Cluster_Machine_LogicalDisk_Keys 7data.Cluster_Machine_LogicalDisk_Sightings 8data.Cluster_Machine_LogicalDisk_UnstableSamples 9data.Cluster_Machine_LogicalDisk_Volume_StableSamples 10data.Cluster_Machine_Memory_Capacity_StableSamples 11data.Cluster_Machine_Memory_UnstableSamples 12data.Cluster_Machine_Network_Capacity_StableSamples 13data.Cluster_Machine_Network_Keys 14data.Cluster_Machine_Network_Sightings 15data.Cluster_Machine_Network_UnstableSamples 16data.Cluster_Machine_OperatingSystem_StableSamples 17data.Cluster_Machine_Ping_UnstableSamples 18data.Cluster_Machine_Process_Instances 19data.Cluster_Machine_Process_Keys 20data.Cluster_Machine_Process_Owner_Instances 21data.Cluster_Machine_Process_Sightings 22data.Cluster_Machine_Process_UnstableSamples 23… There are two things I want to draw your attention to: The table names describe a hierarchy of the different types of object that are monitored by SQL Monitor (e.g. clusters, machines and disks). For each object type in the hierarchy, there are multiple tables, ending in the suffixes _Keys, _Sightings, _StableSamples and _UnstableSamples. Not every object type has a table for every suffix, but the _Keys suffix is especially important and a _Keys table does indeed exist for every object type. In fact, if we limit the query to return only those tables ending in _Keys, we reveal the full object hierarchy: SELECT sch.name + '.' + obj.name AS [name] FROM sys.objects obj JOIN sys.schemas sch ON sch.schema_id = obj.schema_id WHERE obj.type_desc = 'USER_TABLE' AND sch.name = 'data' AND obj.name LIKE '%_Keys' ORDER BY sch.name, obj.name;  name 1data.Cluster_Keys 2data.Cluster_Machine_Keys 3data.Cluster_Machine_LogicalDisk_Keys 4data.Cluster_Machine_Network_Keys 5data.Cluster_Machine_Process_Keys 6data.Cluster_Machine_Services_Keys 7data.Cluster_ResourceGroup_Keys 8data.Cluster_ResourceGroup_Resource_Keys 9data.Cluster_SqlServer_Agent_Job_History_Keys 10data.Cluster_SqlServer_Agent_Job_Keys 11data.Cluster_SqlServer_Database_BackupType_Backup_Keys 12data.Cluster_SqlServer_Database_BackupType_Keys 13data.Cluster_SqlServer_Database_CustomMetric_Keys 14data.Cluster_SqlServer_Database_File_Keys 15data.Cluster_SqlServer_Database_Keys 16data.Cluster_SqlServer_Database_Table_Index_Keys 17data.Cluster_SqlServer_Database_Table_Keys 18data.Cluster_SqlServer_Error_Keys 19data.Cluster_SqlServer_Keys 20data.Cluster_SqlServer_Services_Keys 21data.Cluster_SqlServer_SqlProcess_Keys 22data.Cluster_SqlServer_TopQueries_Keys 23data.Cluster_SqlServer_Trace_Keys 24data.Group_Keys The full object type hierarchy looks like this: Cluster Machine LogicalDisk Network Process Services ResourceGroup Resource SqlServer Agent Job History Database BackupType Backup CustomMetric File Table Index Error Services SqlProcess TopQueries Trace Group Okay, but what about the individual objects themselves represented at each level in this hierarchy? Well that’s what the _Keys tables are for. This is probably best illustrated by way of a simple example – how can I query my own data repository to find the databases on my own PC for which monitoring data has been collected? Like this: SELECT clstr._Name AS cluster_name, srvr._Name AS instance_name, db._Name AS database_name FROM data.Cluster_SqlServer_Database_Keys db JOIN data.Cluster_SqlServer_Keys srvr ON db.ParentId = srvr.Id -- Note here how the parent of a Database is a Server JOIN data.Cluster_Keys clstr ON srvr.ParentId = clstr.Id -- Note here how the parent of a Server is a Cluster WHERE clstr._Name = 'dev-chrisl2' -- This is the hostname of my own PC ORDER BY clstr._Name, srvr._Name, db._Name;  cluster_nameinstance_namedatabase_name 1dev-chrisl2SqlMonitorData 2dev-chrisl2master 3dev-chrisl2model 4dev-chrisl2msdb 5dev-chrisl2mssqlsystemresource 6dev-chrisl2tempdb 7dev-chrisl2sql2005SqlMonitorData 8dev-chrisl2sql2005TestDatabase 9dev-chrisl2sql2005master 10dev-chrisl2sql2005model 11dev-chrisl2sql2005msdb 12dev-chrisl2sql2005mssqlsystemresource 13dev-chrisl2sql2005tempdb 14dev-chrisl2sql2008SqlMonitorData 15dev-chrisl2sql2008master 16dev-chrisl2sql2008model 17dev-chrisl2sql2008msdb 18dev-chrisl2sql2008mssqlsystemresource 19dev-chrisl2sql2008tempdb These results show that I have three SQL Server instances on my machine (a default instance, one named sql2005 and one named sql2008), and each instance has the usual set of system databases, along with a database named SqlMonitorData. Basically, this is where I test SQL Monitor on different versions of SQL Server, when I’m developing. There are a few important things we can learn from this query: Each _Keys table has a column named Id. This is the primary key. Each _Keys table has a column named ParentId. A foreign key relationship is defined between each _Keys table and its parent _Keys table in the hierarchy. There are two exceptions to this, Cluster_Keys and Group_Keys, because clusters and groups live at the root level of the object hierarchy. Each _Keys table has a column named _Name. This is used to uniquely identify objects in the table within the scope of the same shared parent object. Actually, that last item isn’t always true. In some cases, the _Name column is actually called something else. For example, the data.Cluster_Machine_Services_Keys table has a column named _ServiceName instead of _Name (sorry for the inconsistency). In other cases, a name isn’t sufficient to uniquely identify an object. For example, right now my PC has multiple processes running, all sharing the same name, Chrome (one for each tab open in my web-browser). In such cases, multiple columns are used to uniquely identify an object within the scope of the same shared parent object. Well, that’s it for now. I’ve given you enough information for you to explore the _Keys tables to see how objects are stored in your own data repositories. In a future post, I’ll try to explain how monitoring data is stored for each object, using the _StableSamples and _UnstableSamples tables. If you have any questions about this post, or suggestions for future posts, just submit them in the comments section below.

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• CodePlex Daily Summary for Sunday, May 02, 2010

  CodePlex Daily Summary for Sunday, May 02, 2010New ProjectsAdventureWorks in Access: AdventureWorks database in Access format. Data has been ported in Access starting from Adventure Works database for SQL Server 2008.amplifi: This project is still under construction. We will add more information here as soon as it is available.ASP.NET MVC Bug Tracker: Bug Track written in C# ASP.NET MVC 2BigDecimal: BigDecimal is an attempt to create a number class that can have large precision. It is developed in vb.net (.net 4).CBM-Command: Coming soon....Chuyou: ChuyouCMinus: A C Minus Compiler!Complex and advanced mathematical functions: Mathematics toolkit is a Class Library Project which help Programmers to Calculate Mathematics Functions easily.Confuser: Confuser is a obfuscator for .NET. It is developed in C# and using Mono.Cecil for assembly manipulation.easypos: Micro punto de venta que permite ventas express de ropa, que se acopla fácil y transaparente con el ERP Click OneElmech Address Book: Web based Address Book for maintaining details of your business clients. This project targets Suppliers - Traders - Manufacturers - users. Applicat...Feed Viewer: Feed Viewer is able to synchronize subscribed feed and red news among all computers you are using. It understands both RSS and Atom format. It can ...Google URL Shortener, C#: Implementation in C# of generating short URLs by Goo.gl service (Google URL Shortener)MARS - Medical Assistant Record System: MARS - Medical Assistant Record SystemRx Contrib: Rx Contrib is a library which contain extensions for the Rx frameworkSimple Service Administration Tool: A simple tool to start/stop/restart a service of a WinNT based system. The tool is placed in the task bar as a notify icon, so the specified servic...Vis3D: Visual 3D controls for Silverlight.VisContent: XML content controls for ASP.NET.Windows Phone 7 database: This project implements a Isolated Storage (IsolatedStorage) based database for Windows Phone 7. The database consists of table object, each one s...New Releases$log$ / Keyword Substitution / Expansion Check-In Policy (TFS - LogSubstPol): LogSubstPol_v1.2010.0.4 (VS2010): LogSubstPol is a TFS check-in policy which insertes the check-in comments and other keywords into your source code, so you can keep track of the ch...Bojinx: Bojinx Core V4.5.1: The following new features were added: You can now use either BojinxMXMLContext or ContextModule to configure your application or module context. ...CBM-Command: Initial Public Demonstration: Initial public demonstration version. Can browse attached drives and display directory of any attached drive. A common question is "How does it w...Confuser: Confuser v1.0: It is the Confuser v1.0 that used to confuse the reverse-engineers :)Font Family Name Retrieval: 2nd Release: Added New MKV Font Extractor application to showcase the library. MKV Font Extractor depends on MKVToolnix to be installed before it will work. R...Google URL Shortener, C#: Goo.gl-CS v1 Beta: Extract the ZIP file to any location. Two files have to be in the same folder!HouseFly controls: HouseFly controls alpha 0.9.6.1: HouseFly controls release 0.9.6.1 alphaIsWiX: IsWiX 1.0.261.0: Build 1.0.261.0 - built against Fireworks 1.0.264.0. Adds support for VS2010 Integration to support WiX 3.5 beta releases.Managed Extensibility Framework (MEF) Contrib: MefContrib 0.9.2.0: Added conventions based catalog (read more at http://www.thecodejunkie.com/2010/03/bringing-convention-based-registration.html) MEF + Unity integ...MARS - Medical Assistant Record System: license: licenseNSIS Autorun: NSIS Autorun 0.1.5: This release includes source code, executable binary, files and example materials.PHP.net: Release 0.0.0.1: This is the first release of PHP.Net. The features available in this release are: new File Save File Save As Open File In the rar file is th...Rx Contrib: V1: Rx Contrib is ongoing effort for community additions for Rx. Current features are: ReactiveQueue: ISubject that does not loose values if there are ...Silverlight 4.0 Popup Menu: Context Menu for Silverlight 4 v1.0: - Added a margin for icon display. - Added the PopupMenuItem class which is a derivative of the DockPanel. - Find* methods can now drill down the v...Silverlight 4.0 Popup Menu: Context Menu for Silverlight 4 v1.1 Beta: - Added a margin for icon display. - Added the PopupMenuItem class which is a derivative of the DockPanel. - Added a AddSeperator method. - The Fin...Simple Service Administration Tool: SSATool 0.1.3: New Simple Service Administration Tool Version 0.1.3 compiled with Visual Studio .NET 2010.sMAPedit: sMAPedit v0.7a + Map-Pack: Required Additional Map-Pack Added: height setting by color picker (shift+leftclick)sMAPedit: sMAPedit v0.7b: Fixed: force a gargabe collection update to prevent pictureBox's memory leaksqwarea: Sqwarea 0.0.228.0 (alpha): This release corrects a critical bug in ConnexityNotifier service. We strongly recommend you to upgrade to this version. Known bugs : if you open...StackOverflow Desktop Client in C# and WPF: StackOverflow Client 0.1: Source code for the sample.TortoiseHg: TortoiseHg 1.0.2: This is a bug fix release, we recommend all users upgrade to 1.0.2VCC: Latest build, v2.1.30501.0: Automatic drop of latest buildVidCoder: 0.4.0: Changes: Added ability to queue up multiple video files or titles at once. These queued jobs will use the currently selected encoding settings. Mul...WabbitStudio Z80 Software Tools: Wabbitemu 32-bit Test Release: Wabbitemu Visual Studio build for testing purposesWindows Phone 7 database: Initial Release v1.0: This project implements a Isolated Storage (IsolatedStorage) based database for Windows Phone 7. The usage of this software is very simple. You cre...YouTubeEmbeddedVideo WebControl for ASP.NET: VideoControls version 1: This zip file contains the VideoControls.dll, version 1.Most Popular ProjectsRawrWBFS ManagerAJAX Control Toolkitpatterns & practices – Enterprise LibraryMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)iTuner - The iTunes CompanionASP.NETDotNetNuke® Community EditionMost Active Projectspatterns & practices – Enterprise LibraryRawrIonics Isapi Rewrite FilterHydroServer - CUAHSI Hydrologic Information System Serverpatterns & practices: Azure Security GuidanceTinyProjectNB_Store - Free DotNetNuke Ecommerce Catalog ModuleBlogEngine.NETDambach Linear Algebra FrameworkFacebook Developer Toolkit

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• MSCC: Scripting - Administrator's­ toolbox of magic...

  Finally, we made it to have our April meetup - in May. The most obvious explanation is the increased amount of open source and IT activities that either the MSCC, the Linux User Group of Mauritius (LUGM), or the University of Mauritius Student's Computer Club is organising. It's absolutely incredible to see the recent hype of events here on the island. And I'm loving it! Unfortunately, we also had to deal with arranging for a location this time. It was kind of an odyssey as my requests (and phone calls) haven't been answered, even though I tried it several times - well, kind of disappointing and I have to look into that for future gatherings. In my opinion, it is essential that two parameters of a community meeting are fixed as early as possible: Location, and Date and time You can't just change one or both on the very last minute. Well, this time we had to do it due to unforeseen reasons, and I apologise to any MSCC member which couldn't make it to our April meetup. Okay, lesson learned but now back to the actual meetup report ... Shortly after the meeting I placed the following statement as my first impression: "Spontaneous and improvised :) No, seriously, Ish and Dan had well prepared presentations on shell scripting, mainly focused towards Bourne Again Shell (bash), and the pros and cons of scripting versus actually writing something in a decent programming language. I thought that I could cut myself out of the equation but the demand for information about PowerShell was higher than expected..." Well, it turned out that the interest in Windows PowerShell was high, as I even got a couple of questions on it via social media networks during the evening. I also like to mention that the number of attendees went back to what I would call a "standard" number of participation. This time there were 12 craftsmen, but again a good number of First Timers. Reactions of other attendees Here are some impressions and feedback from our participants: "Enjoyed the bash and powershell (linux / windows) presentations ..." -- Nadim on event comments "He [Daniel] also showed us some syntax loopholes in Bash that could leave someone with bad code." -- Ish on MSCC – Let's talk about Scripting   Glad to see a couple of first time attendees, especially students from the university itself. Some details on the presentations MSCC: First time visit at the University of Mauritius - Phase II Engineering Tower, room 2.9 Gimme some love ... bash and other shells Ish gave a great introduction into shell scripting as he spoke about existing shell environments and a little bit about their history. Furthermore, he talked about various built-in commands, the use of coreutils, the ability to daisy-chain multiple commands using pipes, the importance of the standard I/O streams and their file descriptors in advanced scripting techniques. Combined with a couple of sample statements in the Linux terminal on Ubuntu 14.04 machine it was a solid presentation. Have a closer look at his slides - published on his blog on MSCC – Let's talk about Scripting. Oddities of scripting After the brief introduction into bash it was Daniel's turn to highlight a good number of oddities when working with shell scripts. First of all, it should be clear that scripting is not supposed for any kind of implementations in terms of software but simply to automate administrative procedures and to simplify routine jobs on a system. One of the cool oddities that he mentioned is that everything (!) in a shell is represented by strings; there are no other types like integer, float, date-time, etc. that you'd like to use in a full-fledged programming language. Let's have a look at his sample:  more to come... What's the output? As a conclusion, Daniel suggests that shell scripting should be limited but not restricted to automatic repetitive command stacks and batch jobs, startup wrapper for applications in order to set up the execution environment, and other not too sophisticated jobs. But as soon as it might involve a little bit more logic or you might rely on performance it's better to write an application in Ruby, Python, or Perl (among others of course). This is also enables the possibility to test your code properly. MSCC: Ish talking about Bourne Again Shell (bash) and shell scripting to automate regular tasks MSCC: Daniel gives an overview about the pros and cons of shell scripting versus programming MSCC: PowerShell as your scripting solution on Windows operating systems The path of the Enlightened is long ... and tough. Honestly, even though PowerShell was mentioned without any further details on the meetup's agenda, I didn't expect that there would be demand to give a presentation on Microsoft PowerShell after all. I already took this topic out of the announcement but the audience wanted to have some information. Okay, then let's see what I could do - improvised style. While my machine booted and got hooked up to the projector, I started to talk about the beginnings of PowerShell from back in 2006, and its predecessors MS DOS and Command Prompt. A throwback in history... always good for young people. As usual, Microsoft didn't get it at that time. Instead of listening to their client's needs and demands they ignored the feasibility to administrate Windows server farms without any UI tools. PowerShell is actually a result of this, and seeing that shell scripting is a common, reliable and fast way in an administrator's toolbox for decades, Microsoft had to adapt from their Microsoft Management Console (MMC) to a broader approach. It's not like shell scripting was something new; it is in daily use by alternative operating systems like AIX, HP UX, Solaris, and last but not least Linux. Most interestingly, Microsoft is very good at renovating existing architectures, and over the years PowerShell not only replaced their own combination of Command Prompt and Scripting Hosts (VBScript and CScript) but really turned into a challenging competitor on the market. The shell is easy to extend with cmdlets, and open to other Microsoft products like SQL Server, SharePoint, as well as Third-party software applications. Similar to MMC PowerShell also offers the ability to administer other machine remotely - only without a graphical user interface and therefore it's easier to automate and schedule regular tasks. Following is a sample of a PowerShell script file (extension .ps1): $strComputer = "." $colItems = get-wmiobject -class Win32_BIOS -namespace root\CIMV2 -comp $strComputer foreach ($objItem in $colItems) {write-host "BIOS Characteristics: " $objItem.BiosCharacteristicswrite-host "BIOS Version: " $objItem.BIOSVersionwrite-host "Build Number: " $objItem.BuildNumberwrite-host "Caption: " $objItem.Captionwrite-host "Code Set: " $objItem.CodeSetwrite-host "Current Language: " $objItem.CurrentLanguagewrite-host "Description: " $objItem.Descriptionwrite-host "Identification Code: " $objItem.IdentificationCodewrite-host "Installable Languages: " $objItem.InstallableLanguageswrite-host "Installation Date: " $objItem.InstallDatewrite-host "Language Edition: " $objItem.LanguageEditionwrite-host "List Of Languages: " $objItem.ListOfLanguageswrite-host "Manufacturer: " $objItem.Manufacturerwrite-host "Name: " $objItem.Namewrite-host "Other Target Operating System: " $objItem.OtherTargetOSwrite-host "Primary BIOS: " $objItem.PrimaryBIOSwrite-host "Release Date: " $objItem.ReleaseDatewrite-host "Serial Number: " $objItem.SerialNumberwrite-host "SMBIOS BIOS Version: " $objItem.SMBIOSBIOSVersionwrite-host "SMBIOS Major Version: " $objItem.SMBIOSMajorVersionwrite-host "SMBIOS Minor Version: " $objItem.SMBIOSMinorVersionwrite-host "SMBIOS Present: " $objItem.SMBIOSPresentwrite-host "Software Element ID: " $objItem.SoftwareElementIDwrite-host "Software Element State: " $objItem.SoftwareElementStatewrite-host "Status: " $objItem.Statuswrite-host "Target Operating System: " $objItem.TargetOperatingSystemwrite-host "Version: " $objItem.Versionwrite-host} Which gives you information about your BIOS and Windows OS. Then change the computer name to another one on your network (NetBIOS based) and run the script again. There lots of samples and tutorials at the Microsoft Script Center, and I would advise you to pay a visit over there if you are more interested in PowerShell. The Script Center provides the download links, too. Upcoming Events What are the upcoming events here in Mauritius? So far, we have the following ones (incomplete list as usual) in chronological order: Hacking Defence (14. May 2014) WebCup Maurice (7. & 8. June 2014) Developers Conference (TBA ~ July 2014) Linuxfest 2014 (TBA ~ November 2014) Hopefully, there will be more announcements during the next couple of weeks and months. If you know about any other event, like a bootcamp, a code challenge or hackathon here in Mauritius, please drop me a note in the comment section below this article. Thanks! My resume of the day Spontaneous and improvised :) The new location at the University of Mauritius turned out very well, there is plenty of space, and it could be a good choice for future meetings. Especially, having the ability to get more and more students into our IT community sounds like a great opportunity. Later during the day, I got some promising mails from Nadim regarding future sessions at the local branch of the Middlesex University. Well, we will see in the future... But for now this will be on hold until approximately October when students resume their regular studies. Anyway, it was a good experience at the university, and thanks again to the UoM Student's Computer Club that made the necessary arrangements for the MSCC!

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• Setup and Use SpecFlow BDD with DevExpress XAF

  - by Patrick Liekhus

  Let’s get started with using the SpecFlow BDD syntax for writing tests with the DevExpress XAF EasyTest scripting syntax.  In order for this to work you will need to download and install the prerequisites listed below.  Once they are installed follow the steps outlined below and enjoy. Prerequisites Install the following items: DevExpress eXpress Application Framework (XAF) found here SpecFlow found here Liekhus BDD/XAF Testing library found here Assumptions I am going to assume at this point that you have created your XAF application and have your Module, Win.Module and Win ready for usage.  You should have also set any attributes and/or settings as you see fit. Setup So where to start. Create a new testing project within your solution. I typically call this with a similar naming convention as used by XAF, my project name .FunctionalTests (i.e. AlbumManager.FunctionalTests). Add the following references to your project.  It should look like the reference list below. DevExpress.Data.v11.x DevExpress.Persistent.Base.v11.x DevExpress.Persistent.BaseImpl.v11.x DevExpress.Xpo.v11.2 Liekhus.Testing.BDD.Core Liekhus.Testing.BDD.DevExpress TechTalk.SpecFlow TestExecutor.v11.x (found in %Program Files%\DevExpress 2011.x\eXpressApp Framework\Tools\EasyTest Right click the TestExecutor reference and set the “Copy Local” setting to True.  This forces the TestExecutor executable to be available in the bin directory which is where the EasyTest script will be executed further down in the process. Add an Application Configuration File (app.config) to your test application.  You will need to make a few modifications to have SpecFlow generate Microsoft style unit tests.  First add the section handler for SpecFlow and then set your choice of testing framework.  I prefer MS Tests for my projects. Add the EasyTest configuration file to your project.  Add a new XML file and call it Config.xml. Open the properties window for the Config.xml file and set the “Copy to Ouput Directory” to “Copy Always”. You will setup the Config file according to the specifications of the EasyTest library my mapping to your executable and other settings.  You can find the details for the configuration of EasyTest here.  My file looks like this Create a new folder in your test project called “StepDefinitions”.  Add a new SpecFlow Step Definition file item under the StepDefinitions folder.  I typically call this class StepDefinition.cs. Have your step definition inherit from the Liekhus.Testing.BDD.DevExpress.StepDefinition class.  This will give you the default behaviors for your test in the next section. OK.  Now that we have done this series of steps, we will work on simplifying this.  This is an early preview of this new project and is not fully ready for consumption.  If you would like to experiment with it, please feel free.  Our goals are to make this a installable project on it’s own with it’s own project templates and default settings.  This will be coming in later versions.  Currently this project is in Alpha release. Let’s write our first test Remove the basic test that is created for you. We will not use the default test but rather create our own SpecFlow “Feature” files. Add a new item to your project and select the SpecFlow Feature file under C#. Name your feature file as you do your class files after the test they are performing. Writing a feature file uses the Cucumber syntax of Given… When… Then.  Think of it in these terms.  Givens are the pre-conditions for the test.  The Whens are the actual steps for the test being performed.  The Thens are the verification steps that confirm your test either passed or failed.  All of these steps are generated into a an EasyTest format and executed against your XAF project.  You can find more on the Cucumber syntax by using the Secret Ninja Cucumber Scrolls.  This document has several good styles of tests, plus you can get your fill of Chuck Norris vs Ninjas.  Pretty humorous document but full of great content. My first test is going to test the entry of a new Album into the application and is outlined below. The Feature section at the top is more for your documentation purposes.  Try to be descriptive of the test so that it makes sense to the next person behind you.  The Scenario outline is described in the Ninja Scrolls, but think of it as test template.  You can write one test outline and have multiple datasets (Scenarios) executed against that test.  Here are the steps of my test and their descriptions Given I am starting a new test – tells our test to create a new EasyTest file And (Given) the application is open – tells EasyTest to open our application defined in the Config.xml When I am at the “Albums” screen – tells XAF to navigate to the Albums list view And (When) I click the “New:Album” button – tells XAF to click the New Album button on the ribbon And (When) I enter the following information – tells XAF to find the field on the screen and put the value in that field And (When) I click the “Save and Close” button – tells XAF to click the “Save and Close” button on the detail window Then I verify results as “user” – tells the testing framework to execute the EasyTest as your configured user Once you compile and prepare your tests you should see the following in your Test View.  For each of your CreateNewAlbum lines in your scenarios, you will see a new test ready to execute. From here you will use your testing framework of choice to execute the test.  This in turn will execute the EasyTest framework to call back into your XAF application and test your business application. Again, please remember that this is an early preview and we are still working out the details.  Please let us know if you have any comments/questions/concerns. Thanks and happy testing.

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