Search Results

Search found 621 results on 25 pages for 'optimizer transformations'.

Page 19/25 | < Previous Page | 15 16 17 18 19 20 21 22 23 24 25  | Next Page >

• Transform Your Application Integration with Best Practices from Oracle Customers

  - by Lionel Dubreuil

  You want to transform your application integration into an environment based on a service-oriented architecture (SOA). You also want to utilize business process management (BPM) to improve efficiency, deliver business agility, lower total cost of ownership, and increase business visibility. And you want to hear directly from like-minded professionals who have made those types of transformations. Easy enough. Attend this Webcast series to learn from customers who have successfully integrated with Oracle SOA and BPM solutions.Join us for this series and discover how to: Use a single unified platform for all types of processes Increase real-time process visibility Improve efficiency of existing IT investments Lower up-front costs and achieve faster time to market Gain greater benefit from SOA with the addition of BPM Here's the list of upcoming webcasts: “Migrating to SOA at Choice Hotels” on Thurs., June 21, 2012 — 10 a.m. PT / 1 p.m. ET Hear how Choice Hotels successfully made the transition from a complex legacy environment into a SOA-based shared services infrastructure that accelerated time to market as the company implemented its event-driven Google API project. “San Joaquin County—Optimizing Justice and Public Safety with Oracle BPM and Oracle SOA” on Thurs., July 26, 2012 — 10 a.m. PT / 1 p.m. ET Learn how San Joaquin County moved to a service-oriented architecture foundation and business process management platform to gain efficiency and greater visibility into mission-critical information for public safety. “Streamlining Order to Cash with SOA at Eaton” on Thurs., August 23, 2012 — 10 a.m. PT / 1 p.m. ET Discover how Eaton transitioned from a legacy TIBCO infrastructure. Learn about the company’s reference architecture for a SOA-based Oracle Fusion Distributed Order Orchestration (DOO). “Fast BPM Implementation with Fusion: Production in Five Months” on Thurs., September 13, 2012 — 10 a.m. PT / 1 p.m. ET Learn how Nets Denmark A/S implemented Oracle Unified Business Process Management Suite in just five months. The Webcast will cover the implementation from start to production, including integration with legacy systems. “SOA Implementation at Farmers Insurance” on Thurs., October 18, 2012 — 10 a.m. PT / 1 p.m. ET Learn how Farmers Insurance Group lowered application infrastructure costs, reduced time to market, and introduced flexibility by transforming to a SOA-based infrastructure with SOA governance. Register today!

  Read the article

• box2d resize bodies arround point

  - by philipp

  I have a compound object, consisting of a b2Body, vector-graphics and a list polygons which describe the b2body's shapes. This object has its own transformation matrix to centralize the storage of transformations. So far everything is working quiet fine, even scaling works, but not if i scale around a point. In the initialization phase of the object it is scaled around a point. This happens in this order: transform the main matrix transform the vector graphics and the polygons recreate the b2Body After this function ran, the shapes and all the graphics are exactly where they should be, BUT: after the first steps of the b2World the graphical stuff moves away from the body. When I ran the debugger I found out that the position of the body is 0/0 the red dot shows the center of scaling. the first image shows the basic setup and the second the final position of the graphics. This distance stays constant for the rest of the simulation. If I set the position via myBody.SetPosition( sx, sy ); the whole scenario just plays a bit more distant for the origin. Any Idea how to fix this? EDIT:: I came deeper down to the problem and it lies in the fact that i must not scale the transform matrix for the b2body shapes around the center, but set the b2body's position back to the point after scaling. But how can I calculate that point? EDIT 2 :: I came ever deeper down to it, even solved it, but this is a slow solution and i hope that there is somebody who understands what formula I need. assuming to have a set polygons relative to an origin as basis shapes for a b2body: scaling the whole object around a certain point is done in the following steps: i scale everything around the center except the polygons i create a clone of the polygons matrix i scale this clone around the point i calculate dx, dy as difference of clone.tx - original.tx and clone.ty - original.ty i scale the original polygon matrix NOT around the point i recreate the body i create the fixture i set the position of the body to dx and dy done! So what i an interested in is a formula for dx and dy without cloning matrices, scaling the clone around a point, getting dx and dy and finally scale the vertex matrix.

  Read the article

• Obtaining positional information in the IEnumerable Select extension method

  - by Kyle Burns

  This blog entry is intended to provide a narrow and brief look into a way to use the Select extension method that I had until recently overlooked. Every developer who is using IEnumerable extension methods to work with data has been exposed to the Select extension method, because it is a pretty critical piece of almost every query over a collection of objects.  The method is defined on type IEnumerable and takes as its argument a function that accepts an item from the collection and returns an object which will be an item within the returned collection.  This allows you to perform transformations on the source collection.  A somewhat contrived example would be the following code that transforms a collection of strings into a collection of anonymous objects: 1: var media = new[] {"book", "cd", "tape"}; 2: var transformed = media.Select( item => 3: { 4: Media = item 5: } ); This code transforms the array of strings into a collection of objects which each have a string property called Media. If every developer using the LINQ extension methods already knows this, why am I blogging about it?  I’m blogging about it because the method has another overload that I hadn’t seen before I needed it a few weeks back and I thought I would share a little about it with whoever happens upon my blog.  In the other overload, the function defined in the first overload as: 1: Func<TSource, TResult> is instead defined as: 1: Func<TSource, int, TResult>   The additional parameter is an integer representing the current element’s position in the enumerable sequence.  I used this information in what I thought was a pretty cool way to compare collections and I’ll probably blog about that sometime in the near future, but for now we’ll continue with the contrived example I’ve already started to keep things simple and show how this works.  The following code sample shows how the positional information could be used in an alternating color scenario.  I’m using a foreach loop because IEnumerable doesn’t have a ForEach extension, but many libraries do add the ForEach extension to IEnumerable so you can update the code if you’re using one of these libraries or have created your own. 1: var media = new[] {"book", "cd", "tape"}; 2: foreach (var result in media.Select( 3: (item, index) => 4: new { Item = item, Index = index })) 5: { 6: Console.ForegroundColor = result.Index % 2 == 0 7: ? ConsoleColor.Blue : ConsoleColor.Yellow; 8: Console.WriteLine(result.Item); 9: }

  Read the article

• Synchronizing ODSEE and OUD

  - by Etienne Remillon

  When it comes to synchronizing between ODSEE and OUD, what should be the best options ? Couple  options are available - Use one of OUD internal capability called Replication Gateway - Use our synchronization tool called Directory Integration Platform part of Oracle Directory Services Plus - Manuel export and import Let's check pro and cons on each method. Replication Gateway is the natural, out of the box solution to perform the task. We created this as a feature of OUD because it works at our replication protocol level. The gateway perform the required adaptation between the ODSEE's replication protocol and OUD's one. The benefits of doing this is that it provide strong consistency between the to type of directories. This fully leverage conflict management implemented in the replication protocols to ensure that changes are applied in a coherent and ordered manner. It does not require specific modification on existing ODSEE production instances such as turning on "retro changelog". Changes are propagated at near speed of replication in both directions. Replication Gateway can also synchronize information that are stored internally in the directory server such as "xxxxx" account locking managed at ODSEE server level and not via the nsyyyy attribute. OUD replication gateway does no require any specific tools or installation specific procedure. It is manged like other OUD component with monitoring and configuration via the standard console. OUD Replication Gateway does not perform adaptation between ODSEE and OUD. Using Directory Integration Protocol as external component to OUD, brings flexibility in remapping and transformations between ODSEE and OUD. There is a price to pay in using DIP to perform the synchronization task. You will have to turn on the retro change log to get access to changes on the ODSEE side (this will impact disk and CPU usage and performances which could be a serious challenge for your existing ODSEE environment (if you have not provisioned additional hardware and instances). You will not benefits of conflict resolution management and this might have to be addressed at application level, which is not always possible to implement. Using export and import seams very simple, but this methodology cannot ensure an highly available deployment with up to date entries on booth sides. This solution can be used if full HA with up-to-date data is not needed (during synchronization time). It often used  if data-cleaning need to take place to avoid polluting a new environment with old un-necessary data.

  Read the article

• Is MongoDB a good choice or not for my application?

  - by shubham

  I have a Reporting application which stores the reports in xml format as recieved from source (XML schema is not defined, it can be any format) and those reports contain some keys and values. Like jobid, setid be keys for 1 type of report and userid, groupId for another type of report etc. The type of keys that can be referred from the document is determined by the namespaces used in the xml doc. These keys are stored on the basis of namespace used in the xml document. For e.g. If a tag in xml fragment uses namespace= "myspace1", then I have keys A and B for myspace1 stored in another table. It will fetch those keys from that table for this namespace, look for their values in xml doc and store it in another table along with the pointer to this xml document (Id of a record storing complete xml document in a cell). Use cases: When the user comes and queries for that key and value, I return the document or a set of documents that are having those key/value pairs. When the user comes and queries for a certain key and provide a name for xslt (pre stored), I fetch the set of documents fulfilling that criteria and convert that xml to html with the specified xslt. When the user comes and asks for a particular fragment of a doc then it can fetch a subset from a particular document also. When the user comes and queries for top x values of a certain key, I return the set of documents that are having top 10 values of that key. I am using DB2 database for its support of xml along with relational capabilities. That makes easier for me to run xpath expressions and fetch values of keys and also aggregate a set of documents fullfilling a criteria, all on the database side. Problems: DB2 stores XML doc of upto 2GB in size. Retrieval is very slow. If some thing involves many documents, then it takes significant time for things to show up in browser, and the user has to wait. Can MongoDb help in this case, as it is document oriented? can I do xml related xpath queries and document transformations on db side? Or is it ok to use both in such a case?

  Read the article

• What Precalculus knowledge is required before learning Discrete Math Computer Science topics?

  - by Ein Doofus

  Below I've listed the chapters from a Precalculus book as well as the author recommended Computer Science chapters from a Discrete Mathematics book. Although these chapters are from two specific books on these subjects I believe the topics are generally the same between any Precalc or Discrete Math book. What Precalculus topics should one know before starting these Discrete Math Computer Science topics?: Discrete Mathematics CS Chapters 1.1 Propositional Logic 1.2 Propositional Equivalences 1.3 Predicates and Quantifiers 1.4 Nested Quantifiers 1.5 Rules of Inference 1.6 Introduction to Proofs 1.7 Proof Methods and Strategy 2.1 Sets 2.2 Set Operations 2.3 Functions 2.4 Sequences and Summations 3.1 Algorithms 3.2 The Growths of Functions 3.3 Complexity of Algorithms 3.4 The Integers and Division 3.5 Primes and Greatest Common Divisors 3.6 Integers and Algorithms 3.8 Matrices 4.1 Mathematical Induction 4.2 Strong Induction and Well-Ordering 4.3 Recursive Definitions and Structural Induction 4.4 Recursive Algorithms 4.5 Program Correctness 5.1 The Basics of Counting 5.2 The Pigeonhole Principle 5.3 Permutations and Combinations 5.6 Generating Permutations and Combinations 6.1 An Introduction to Discrete Probability 6.4 Expected Value and Variance 7.1 Recurrence Relations 7.3 Divide-and-Conquer Algorithms and Recurrence Relations 7.5 Inclusion-Exclusion 8.1 Relations and Their Properties 8.2 n-ary Relations and Their Applications 8.3 Representing Relations 8.5 Equivalence Relations 9.1 Graphs and Graph Models 9.2 Graph Terminology and Special Types of Graphs 9.3 Representing Graphs and Graph Isomorphism 9.4 Connectivity 9.5 Euler and Hamilton Ptahs 10.1 Introduction to Trees 10.2 Application of Trees 10.3 Tree Traversal 11.1 Boolean Functions 11.2 Representing Boolean Functions 11.3 Logic Gates 11.4 Minimization of Circuits 12.1 Language and Grammars 12.2 Finite-State Machines with Output 12.3 Finite-State Machines with No Output 12.4 Language Recognition 12.5 Turing Machines Precalculus Chapters R.1 The Real-Number System R.2 Integer Exponents, Scientific Notation, and Order of Operations R.3 Addition, Subtraction, and Multiplication of Polynomials R.4 Factoring R.5 Rational Expressions R.6 Radical Notation and Rational Exponents R.7 The Basics of Equation Solving 1.1 Functions, Graphs, Graphers 1.2 Linear Functions, Slope, and Applications 1.3 Modeling: Data Analysis, Curve Fitting, and Linear Regression 1.4 More on Functions 1.5 Symmetry and Transformations 1.6 Variation and Applications 1.7 Distance, Midpoints, and Circles 2.1 Zeros of Linear Functions and Models 2.2 The Complex Numbers 2.3 Zeros of Quadratic Functions and Models 2.4 Analyzing Graphs of Quadratic Functions 2.5 Modeling: Data Analysis, Curve Fitting, and Quadratic Regression 2.6 Zeros and More Equation Solving 2.7 Solving Inequalities 3.1 Polynomial Functions and Modeling 3.2 Polynomial Division; The Remainder and Factor Theorems 3.3 Theorems about Zeros of Polynomial Functions 3.4 Rational Functions 3.5 Polynomial and Rational Inequalities 4.1 Composite and Inverse Functions 4.2 Exponential Functions and Graphs 4.3 Logarithmic Functions and Graphs 4.4 Properties of Logarithmic Functions 4.5 Solving Exponential and Logarithmic Equations 4.6 Applications and Models: Growth and Decay 5.1 Systems of Equations in Two Variables 5.2 System of Equations in Three Variables 5.3 Matrices and Systems of Equations 5.4 Matrix Operations 5.5 Inverses of Matrices 5.6 System of Inequalities and Linear Programming 5.7 Partial Fractions 6.1 The Parabola 6.2 The Circle and Ellipse 6.3 The Hyperbola 6.4 Nonlinear Systems of Equations

  Read the article

• MySQL Connect in Only 5 Days – Some Fun Stuff!

  - by Bertrand Matthelié

  72 1024x768 Normal 0 false false false EN-US X-NONE 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-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} We’ve recently blogged about the various MySQL Connect sessions focused on MySQL Cluster, InnoDB, the MySQL Optimizer and MySQL Replication. But we also wanted to draw your attention to some great opportunities to network and have fun! That’s also part of what makes a good conference... MySQL Connect Reception San Francisco Hilton - Continental Ballroom 6:30 p.m.–8:30 p.m. A great opportunity to network with Oracle’s MySQL engineers, partners having a booth in the exhibition hall and just about everyone at MySQL Connect. Long time MySQL users will see many familiar faces, and new users will be able to build valuable relationships. A must attend reception for sure! Taylor Street Open House 7:00 p.m.–9:00 p.m. After two intense days at MySQL Connect, you’ll get the chance to relax and continue networking at the Taylor Street Café Open House on Sunday evening. Perhaps recharging batteries for a full week at Oracle OpenWorld… The Oracle OpenWorld Music Festival Starting on Sunday eve and running through the entire duration of Oracle OpenWorld, the first Oracle OpenWorld Musical Festival features some of today’s breakthrough musicians. It’s five nights of back-to-back performances in the heart of San Francisco. Registered Oracle conference attendees get free admission, so remember your badge when you head to a show. More information here. You can check out the full MySQL Connect program here as well as in the September edition of the MySQL newsletter. Not registered yet? You can still save US$ 300 over the on-site fee – Register Now!

  Read the article

• Attaching two objects and changing their world matrices accordingly

  - by A-Type

  I'm having a hard time wrapping my head around the transformations required to bind two objects together in either a two-way or one-way relationship. I will need to implement both types. For the first case, I want to be able to 'couple' two ships together in space. The ships have different mass, of course. Forces applied to either ship will use combined mass and moment of inertia to calculate and move both ships. The trick is, being sure that the point at which they are coupled remains the same, and they don't move at all relative to each other. The second case is similar: I want a ship to be able to enter the atmosphere of a planet and move relative to the planet. The planet will be orbiting the sun, which is fixed at 0,0,0. Essentially, when the ship is sitting still outside of the atmosphere, the planet will move past it on its course-- but when the ship is sitting still inside the atmosphere, it moves and rotates with the planet, so that it is always relative to the horizon. Essentially, the vertices which make up the ship are now transformed just like the ones that make up the planet, except that the ship can move itself around relative to the planet. I get the feeling I can implement both of these with the same code. Essentially, I am thinking of giving each object (which I call Fixtures) a list of "slave" Fixtures onto which that Fixture's world matrix is imposed. So, this would be the planet imposing its world on any contained ships. In the case of coupling, I would simply make each ship a slave of the other, somehow. Obviously I can't just multiply the ship's world matrix by the planet's, or each ship by the others. What I'd like some help with is what calculations to make in order to get a nice, seamless relative world to the other object. I was thinking maybe I could just multiply the world of the slave by the inverse of the master, but then when you couple two ships you would lose all that world data. So, perhaps I need an intermediate "world" which is the absolute world, but use a secondary "final world" to actually transform the objects?

  Read the article

• Enterprise Manager 12c: New DSS Demos Available

  - by Javier Puerta

  Enterprise Manager Cloud Control 12c Application Replay Demo Now Available! User Experience Monitoring with Enterprise Manager Cloud Control 12c and Real User Experience Insight 12R1 Now Available! Oracle Enterprise Manager Cloud Control 12c: Database Management Packs demo upgrade     Enterprise Manager Cloud Control 12c Application Replay Demo Now Available! We are pleased to announce the availability of the Oracle Application Replay demo that showcases some of the key capabilities of performing realistic, production scale testing of your web and packaged Oracle applications. This demo specifically focuses on capturing production web traffic from an E-Business Suite application and replaying the captured workload on a test E-Business Suite application to assess the impact of an application infrastructure change on the workload. The target audiences are application developers, quality assurance teams, IT managers and production control staff that deal in day-to-day change management activities and trouble shooting of production environments. Demo Highlights: Enterprise Manager 12c workflows for capturing application workload Seamless integration of Application Replay with Real User Experience Insight for application workload capture Enterprise Manager 12c centralized workflows for replaying captured application workloads in a test environment Demonstrates how to minimize risk when deploying a complex EBusiness Suite application infrastructure change. Rich reporting capability for performance analysis and problem detection User Experience Monitoring with Enterprise Manager Cloud Control 12c and Real User Experience Insight 12R1 Now Available! We are pleased to announce the availability of the Oracle Real User Experience Insight demo that showcases some of the key capabilities of user experience monitoring. This demo specifically focuses on business reporting, integrated performance diagnostics, tracking of customer journey’s through RUEI’s userflow tracking capabilities and it’s Key Performance Indicators tracking and configuration. Demo Highlights: Application-centric dashboard Integration with Oracle Enterprise Manager 12c – JVMD, ADP and BTM Session diagnostics and user session replay Monitoring through “Key Performance Indicators” (KPI) --- create alerts/incidents FUSION Application centric dashboards & integrated BI Oracle Enterprise Manager Cloud Control 12c: Database Management Packs demo upgrade DSS is pleased to announce an upgrade to the Oracle Enterprise Manager Cloud Control 12c: Database Management Packs demo. While retaining the content from the initial release of the demo—Diagnostic and Tuning Packs, Test Data Management and Data Masking, and Real Application Testing—the demo now includes a new Data Masking for Real Application Testing scenario. Demo Features: Diagnostic and Tuning Packs SQL Performance Analyzer Database Replay Data Masking Masking Real Application Testing workloads Testing pending Optimizer statistics Test Data Management

  Read the article

• How can I achieve a 3D-like effect with spritebatch's rotation and scale parameters

  - by Alic44

  I'm working on a 2d game with a top-down perspective similar to Secret of Mana and the 2D Final Fantasy games, with one big difference being that it's an action rpg using a 3-dimensional physics engine. I'm trying to draw an aimer graphic (basically an arrow) at my characters' feet when they're aiming a ranged weapon. At first I just converted the character's aim vector to radians and passed that into spritebatch, but there was a problem. The position of every object in my world is scaled for perspective when it's drawn to the screen. So if the physics engine coordinates are (1, 0, 1), the screen coords are actually (1, .707) -- the Y and Z axis are scaled by a perspective factor of .707 and then added together to get the screen coordinates. This meant that the direction the aimer graphic pointed (thanks to its rotation value passed into spritebatch) didn't match up with the direction the projectile actually traveled over time. Things looked fine when the characters fired left, right, up, or down, but if you fired on a diagonal the perspective of the physics engine didn't match with the simplistic way I was converting the character's aim direction to a screen rotation. Ok, fast forward to now: I've got the aimer's rotation matched up with the path the projectile will actually take, which I'm doing by decomposing a transform matrix which I build from two rotation matrices (one to represent the aimer's rotation, and one to represent the camera's 45 degree rotation on the x axis). My question is, is there a way to get not just rotation from a series of matrix transformations, but to also get a Vector2 scale which would give the aimer the appearance of being a 3d object, being warped by perspective? Orthographic perspective is what I'm going for, I think. So, the aimer arrow would get longer when facing sideways, and shorter when facing north and south because of the perspective. At the same time, it would get wider when facing north and south, and less wide when facing right or left. I'd like to avoid actually drawing the aimer texture in 3d because I'm still using spritebatch's layerdepth parameter at this point in my project, and I don't want to have to figure out how to draw a 3d object within the depth sorting system I already have. I can provide code and more details if this is too vague as a question... This is my first post on stack exchange. Thanks a lot for reading! Note: (I think) I realize it can't be a technically correct 3D perspective, because the spritebatch's vector2 scaling argument doesn't allow for an object to be skewed the way it actually should be. What I'm really interested in is, is there a good way to fake the effect, or should I just drop it and not scale at all? Edit to clarify without the help of a picture (apparently I can't post them yet): I want the aimer arrow to look like it has been painted on the ground at the character's feet, so it should appear to be drawn on the ground plane (in my case the XZ plane) which should be tilted at a 45 degree angle (around the X axis) from the viewing perspective. Alex

  Read the article

• SQL Saturday 194 - Exeter

  - by Dave Ballantyne

  Many kudos goes to Jonathan and Annette Allen and the others on the team for confirming SQL Saturday 194 in Exeter on the 8th and 9th of March.  The event home page is here http://www.sqlsaturday.com/194/eventhome.aspx and I delighted that myself and Dave Morrison will be presenting a full day pre-con on the 8th on favourite subjects “TSQL and Internals”. Here is the full abstract : TSQL and internals - When faced with performance issues there are many lines of attack. Tuning the engine itself can get you so far, however for maximum effect you need to understand how the engine and how it translates SQL statements into performable actions. This is not a simple task, it is a massive task to deal with a multi-table join and the number of permutations can be immense. To back up this knowledge, we can create better performing TSQL and understand the impact that is has upon the engine and recognize the pitfalls and gotcha’s that exist in SQLServer. Ultimately, there is no ‘best way’ to perform a single task only many variations of ‘it depends’ , but now we can pick the most appropriate option for the required dataload. Over the years, there have been many myths and misconceptions have grown around the product, some have basis in older versions and some are just wrong. Continuing to build on the knowledge given so far these issue will be explored and broken down and proved or disproved. Finally we will look to the future and explore SQL Server 2012 and the new functionality that that brings and some of the common uses that we will be able to address. After completion of this days pre-con, attendees will have a more complete knowledge of execution plans, and how they relate to the physical and logical actions that SQLServer will be executing on their behalf. The attendees will also have a more rounded and fuller knowledge of TSQL and the implications of incorrectly defining a query. Dave is a fountain of knowledge on execution plans and optimizer internals and ,though i may flatter myself, I’m no shrinking violet when it comes to TSQL and such matters.  I hope that if you cant join us, then there are other pre-cons available from other experts in their fields that may ‘float you boat’ too.  The pre-con page is http://sqlsouthwest.co.uk/SQLSaturday_precon.htm Also, excitingly, this pre-con day is sponsored by Fusion-IO which is a great boon for the day. If you want a more of this then i am offering a 2 day TSQL course starting on the 19th of March. More details on this are available here

  Read the article

• Upgrading from SQL2000 database to SQL Express 2008 R2

  - by itwb

  Hi, We have a web application which uses a MSSQL 2000 backend database. We are currently paying a ridiculous amount for Shared Hosting, with the database costs alone costing us $150 per month (MSSQL 100mb extra space is $40 per month). Our database size is 896.38 MB I am looking at getting a Virtual Private Server and upgrading the database to a MSSQL2008 Express database. I am aware that the Express version is limited to a 10GB database (with R2), and is constrained to a single CPU. I have also been offered SQL Server 2008 Web Edition for $19/per month, but I cannot find many details on the difference between Express and Web. Any suggestions here? What I would also like to know is: If we upgrade the database to MSSQL 2008 database, is there any issues with possible data transformations in the future? I.e. Is it possible to download and mount it with SQL Server 2008 Standard edition? I'm more concerned about how to get data in and out of the database through SQL Management tools. Are there any other issues that I might face? Thanks, Mike

  Read the article

• PhpMyAdmin Missing parameter:

  - by Ali

  Everything was working fine until this moment I want to create a new database and I'm receiving this error db_create.php: Missing parameter: new_db (FAQ 2.8) Also when I was trying to export my database I also receive the following error export.php: Missing parameter: what (FAQ 2.8) export.php: Missing parameter: export_type (FAQ 2.8) When I looked it FAQ 2.8 from the suggested link in PHPMYADMIN 2.8 I get "Missing parameters" errors, what can I do? Here are a few points to check: In config.inc.php, try to leave the $cfg['PmaAbsoluteUri'] directive empty. See also FAQ 4.7. Maybe you have a broken PHP installation or you need to upgrade your Zend Optimizer. See http://bugs.php.net/bug.php?id=31134. If you are using Hardened PHP with the ini directive varfilter.max_request_variables set to the default (200) or another low value, you could get this error if your table has a high number of columns. Adjust this setting accordingly. (Thanks to Klaus Dorninger for the hint). In the php.ini directive arg_separator.input, a value of ";" will cause this error. Replace it with "&;". If you are using Hardened-PHP, you might want to increase request limits. The directory specified in the php.ini directive session.save_path does not exist or is read-only. I did tried with php.ini to make sure that I've session.save_path = "/tmp" I'm using Mac Xserver and running with MAMP I did tried everything to restart my server and nothing help. Please if anyone help me to give me some suggestion. Apologize if I post in a wrong place.

  Read the article

• eAccelerator Issue - Cache Directory Empty.

  - by Tom

  Hi all, Hoping someone can give me a hand with this. I've recently installated eAccelerator 0.9.6.1 - On a CentOS LAMP server. Had it working fine, using the /tmp/accelerator as the cache directory. php.ini set up: zend_extension="/usr/local/lib/php/extensions/no-debug-non-zts-20060613/eaccelerator.so" eaccelerator.shm_size="200" eaccelerator.cache_dir="/var/cache/eaccelerator" eaccelerator.enable="1" eaccelerator.optimizer="1" eaccelerator.check_mtime="1" eaccelerator.debug="0" eaccelerator.filter="" eaccelerator.shm_max="0" eaccelerator.shm_ttl="3600" eaccelerator.shm_prune_period="180" eaccelerator.shm_only="1" eaccelerator.compress="1" eaccelerator.compress_level="9" php -v output: PHP 5.2.12 (cli) (built: Feb 3 2010 00:34:28) Copyright (c) 1997-2009 The PHP Group Zend Engine v2.2.0, Copyright (c) 1998-2009 Zend Technologies with eAccelerator v0.9.6.1, Copyright (c) 2004-2010 eAccelerator, by eAccelerator with the ionCube PHP Loader v3.3.20, Copyright (c) 2002-2010, by ionCube Ltd. I had to remove the cache directory as I was testing something. Remade it, re-set permissions and found that eAccelerator was no longer creating cache files within the folder. I thought it might be down to ownership rights on the folder so chown'd it apache.apache and this made no difference. I recreated the directory in /var/cache instead and editted php.ini to point to the new cache dir location, chmod'd, chown'd etc. and still eAccelerator is not creating any of the cache files in the directory (just empty). Could someone suggest what I might be doing incorrectly here. I've read through numerous pages to try and troubleshoot the issue to no avail. Any help appreciated.

  Read the article

• ADFS v.2.0 transitive trust in a federation scenario

  - by masi

  Currently i'm working with ADFS to establish a federated trust between two separated domains. My question is simple: does ADFS v. 2.0 support transitive trust across federated identity providers? I know that ADFS v 1.0 does not, as stated in this document on page 9. But when looking on the claims rules that come with ADFS 2.0 it seems to be possible, as a Microsoft partner confirmed. However: the documentation on this topic is a mess! Simply no ADFS v. 2.0 related statements on this topic that i was able to find (IF you got any documentation on this PLEASE help me out guys!). To be more clear, lets assume this scenario: Federation provider (A) trust federation provider (B) which trusts identity provider (C). So, does (A) trust identities comming from (C) across (B)? Also, if it is possible there are some things that i'm specially interested in: Is it possible to restrict the transitive trust in ADFS in any way? If so, how? How does the transitive trust affect the Issuer and OriginalIssuer properties of the claims? If transitive trust is used together with claims transformations and provider (B) would transform incomming claims from (C) in a way that they are transformed into (new) claims of same type an value, how would this affect the Issuer and OriginalIssuer properties?

  Read the article

• How to stop Firefox on an SSD from freezing when using the search box or submitting a form?

  - by sblair

  Firefox usually freezes for about a second whenever I search for something from the toolbar search box, when submitting a form, or when clearing the search box history. I suspect it has something to do with the auto-complete feature. Using Windows 7's Resource Monitor, the problem seems to be from the file: C:\Users\<username>\AppData\Roaming\Mozilla\Firefox\Profiles\<profile>\formhistory.sqlite-journal I believe this is a temporary file which caches database writes. The following screenshot shows the very high response times from six different searches, and that the queue length on drive C shoots off the scale: My Firefox profile is on an Intel X25-M G2 SSD. The problem doesn't seem to occur if I create a new profile on a hard disk drive. However, I'd like to know why the problem exists on the SSD in the first place (because it's an annoying problem which contradicts the reason I bought an SSD, and it might happen with other applications too), and how to prevent it. It still occurs if Firefox is started in safe mode, and with the recent beta versions. Updates: VACUUMing the Firefox profile databases does not help with this problem. The SSD Optimizer in the Intel SSD Toolbox does not help either.

  Read the article

• After upgrading to 2008 R2 Enterprise and installing more RAM, Windows can only see 4.00 GB

  - by Tom Crane

  (I have also posted this on technet but I'm running out of ideas) I've upgraded from Windows Server 2008 R2 Standard to Enterprise in order to make use of more RAM. The server previously had 32GB of RAM. The upgrade from Standard to Enterprise, using DISM, seemed to go OK, so I powered down and installed the RAM. This a Dell Poweredge T710, I was taking it from 32GB to 72GB. The BIOS recognised the RAM, although I needed to change from "Advanced ECC" to "Optimizer" mode for it to use all of it. After rebooting, windows can see the RAM but in the system panel will display: Installed memory (RAM): 72.0 GB (4.00 GB usable) In the resource monitor, the remainder of the RAM is showing as reserved for hardware. I've tried various RAM configurations, including reverting it to the same chips and same configuration as before the upgrade, but always just 4.00 GB is showing up as usable. Following some threads on these forums I've gone into msconfig and set the maximum memory "by hand" but that doesn't fix the problem. BIOS doesn't seem to have anything that looks like memory remapping which is another suggestion that has come up. How do I make this RAM available to Windows? It was available before the upgrade, because I could use the full 32GB RAM the server had to start with. A screenshot (this is after reverting to the original RAM configuration) http://screencast.com/t/5FuzevdNb I don't know if it's related, but my remote desktop configuration has also disappeared: screencast.com/t/mYedomeQWS (the bottom half of this dialog should allow me to configure Remote Desktop, it was working before the upgrade but now it isn't).

  Read the article

• Gifsicle: How to set it to not overwrite the original GIF file if the resulting modified GIF file is larger than the original?

  - by galacticninja

  About Gifsicle: Gifsicle is a command-line tool for creating, editing, and getting information about GIF images and animations. One of its features is (from its website): Optimize your animations! This stores only the changed portion of each frame, and can radically shrink your GIFs. You can also use transparency to make them even smaller. Gifsicle’s optimizer is pretty powerful, and usually reduces animations to within a couple bytes of the best commercial optimizers. I call Gifsicle through this .BAT file in the Right Click - 'Send to' Menu: @echo off :compressFile "C:\Programs\Compression Scripts\gifsicle\bin\gifsicle.exe" --batch -V -O3 %1% echo. echo. SHIFT if exist %1% goto compressFile PAUSE This animated GIF file, however: http://i.minus.com/i7WdodY5Zwot3.gif, when its compression is optimized with Gifsicle with the above commands, results in a larger-filesized GIF file. Gifsicle overwrites the original GIF file with the resulting larger-filesized GIF file. Initial filesize: 7.57 MiB (7,942,886 bytes). After running through the above commands with Gifsicle: 7.64 MiB (8,017,622 bytes). Is there a way to prevent Gifsicle from overwriting the original file if its output file is larger than the original file, while still overwriting the original file if the output file is smaller? Details: OS: Windows 7 Gifsicle version: 1.63, from the binary provided here: http://www.lcdf.org/gifsicle/ Gifsicle manual

  Read the article

• High-performance Academic Server [closed]

  - by PHPsmith

  Suppose I want to build a server for the university's academic interests. The server is dedicated only to a site, where users (students and lecturers) just view and fill the academic data. But at a time (e.g. once a semester), about 12,000 students will access the site simultaneously. Due to limitation of resources, I have to build the server using free software (except for the operating system Windows 7, the university has been prepared). The hardware is also limited to the usual 4-core computers (eg, Ivy Bridge Intel Core i7-3770) with approximately 16GB of memory (DDR3 1600 MHz), equipped with an RJ-45 port (Intel 82 579 Gigabit Ethernet). With all these limitations, I have to choose the software (web server, database, etc) are appropriate for this purpose is achieved. I decided to create a site in PHP. Please help me by answering the following questions based on your expertise. (my prime candidate software to consider after googling) Web server which is faster & stable & secure, when implemented and optimized for PHP? And why? (nginx) PHP accelerator which is faster & stable & compatible with the selected web server? And why? (APC with Zend Optimizer+) Database which is faster & stable & secure, when implemented and optimized for selected web server and selected PHP accelerator? (MySQL) Are there any errors that have been or will be happening from my condition is? If there is, please enlighten me? Is there anything else I need to know in order to achieve this goal? If there is, please enlighten me? I understand that the performance also depends on the implementation of source-code program, so I assume it will create a site with the best efficiency (e.g. using AJAX).

  Read the article

• Ubuntu + LigHTTPd: Server requests taking ages

  - by ctrl_freak

  I've had an issue since upgrading my distro a couple of weeks ago from hardy; receiving data after making a request has increasing intervals of nothing, as you can see from the picture below. http://i49.tinypic.com/2w5lvr9.png I have since reinstalled fresh from an Ubuntu 10.04 Server (i386) disk, but am still having the same issues. I'm running on a LigHTTPd, MySQL, PHP5 stack. The surprising thing is, that local browsing using lynx is super fast, as expected. Initially, after reinstalling, I copied over the old configuration files from the previous installation, but have since reinstalled LigHTTPd and rebuilt the config file from scratch. The only correlation I could find, was that I attempted installation of ionCube and Zend Optimizer for a script I was testing, however I would think that it could no longer impact seeing I had reinstalled the OS. I have also removed Suhosin just in case, however it had no impact. I'm thinking it possibly has something to do with networking, but I wouldn't know where to start. The server is manually assigned an IP by it's MAC address on the router. The fact that the time seems to be exponential (to a point) worries me. I've tried strace'ing the LigHTTPd and MySQL processes, however I couldn't see anything obvious, not that I'd really know what I'm looking for. RAM and CPU usage don't seem to be out of the ordinary, but I can't say its perfect.. I'm hoping someone has experienced the same, or can point me in a direction, as searching has proved fruitless as I don't know anything specific. Config files can be posted, if requested.

  Read the article

• SharePoint.DesignFactory.ContentFiles–building WCM sites

  - by svdoever

  One of the use cases where we use the SharePoint.DesignFactory.ContentFiles tooling is in building SharePoint Publishing (WCM) solutions for SharePoint 2007, SharePoint 2010 and Office365. Publishing solutions are often solutions that have one instance, the publishing site (possibly with subsites), that in most cases need to go through DTAP. If you dissect a publishing site, in most case you have the following findings: The publishing site spans a site collection The branding of the site is specified in the root site, because: Master pages live in the root site (/_catalogs/masterpage) Page layouts live in the root site (/_catalogs/masterpage) The style library lives in the root site ( /Style Library) and contains images, css, javascript, xslt transformations for your CQWP’s, … Preconfigured web parts live in the root site (/_catalogs/wp) The root site and subsites contains a document library called Pages (or your language-specific version of it) containing publishing pages using the page layouts and master pages The site collection contains content types, fields and lists When using the SharePoint.DesignFactory.ContentFiles tooling it is very easy to create, test, package and deploy the artifacts that can be uploaded to the SharePoint content database. This can be done in a fast and simple way without the need to create and deploy WSP packages. If we look at the above list of artifacts we can use SharePoint.DesignFactory.ContentFiles for master pages, page layouts, the style library, web part configurations, and initial publishing pages (these are normally made through the SharePoint web UI). Some artifacts like content types, fields and lists in the above list can NOT be handled by SharePoint.DesignFactory.ContentFiles, because they can’t be uploaded to the SharePoint content database. The good thing is that these artifacts are the artifacts that don’t change that much in the development of a SharePoint Publishing solution. There are however multiple ways to create these artifacts: Use paper script: create them manually in each of the environments based on documentation Automate the creation of the artifacts using (PowerShell) script Develop a WSP package to create these artifacts I’m not a big fan of the third option (see my blog post Thoughts on building deployable and updatable SharePoint solutions). It is a lot of work to create content types, fields and list definitions using all kind of XML files, and it is not allowed to modify these artifacts when in use. I know… SharePoint 2010 has some content type upgrade possibilities, but I think it is just too cumbersome. The first option has the problem that content types and fields get ID’s, and that these ID’s must be used by the metadata on for example page layouts. No problem for SharePoint.DesignFactory.ContentFiles, because it supports deploy-time resolving of these ID’s using PowerShell. For example consider the following metadata definition for the page layout contactpage-wcm.aspx.properties.ps1: Metadata page layout # This script must return a hashtable @{ name=value; ... } of field name-value pairs # for the content file that this script applies to. # On deployment to SharePoint, these values are written as fields in the corresponding list item (if any) # Note that fields must exist; they can be updated but not created or deleted. # This script is called right after the file is deployed to SharePoint.   # You can use the script parameters and arbitrary PowerShell code to interact with SharePoint. # e.g. to calculate properties and values at deployment time.   param([string]$SourcePath, [string]$RelativeUrl, $Context) @{     "ContentTypeId" = $Context.GetContentTypeID('GeneralPage');     "MasterPageDescription" = "Cloud Aviator Contact pagelayout (wcm - don't use)";     "PublishingHidden" = "1";     "PublishingAssociatedContentType" = $Context.GetAssociatedContentTypeInfo('GeneralPage') } The PowerShell functions GetContentTypeID and GetAssociatedContentTypeInfo can at deploy-time resolve the required information from the server we are deploying to. I personally prefer the second option: automate creation through PowerShell, because there are PowerShell scripts available to export content types and fields. An example project structure for a typical SharePoint WCM site looks like: Note that this project uses DualLayout. So if you build Publishing sites using SharePoint, checkout out the completely free SharePoint.DesignFactory.ContentFiles tooling and start flying!

  Read the article

• “Query cost (relative to the batch)” <> Query cost relative to batch

  - by Dave Ballantyne

  OK, so that is quite a contradictory title, but unfortunately it is true that a common misconception is that the query with the highest percentage relative to batch is the worst performing.  Simply put, it is a lie, or more accurately we dont understand what these figures mean. Consider the two below simple queries: SELECT * FROM Person.BusinessEntity JOIN Person.BusinessEntityAddress ON Person.BusinessEntity.BusinessEntityID = Person.BusinessEntityAddress.BusinessEntityID go SELECT * FROM Sales.SalesOrderDetail JOIN Sales.SalesOrderHeader ON Sales.SalesOrderDetail.SalesOrderID = Sales.SalesOrderHeader.SalesOrderID After executing these and looking at the plans, I see this : So, a 13% / 87% split ,  but 13% / 87% of WHAT ? CPU ? Duration ? Reads ? Writes ? or some magical weighted algorithm ?  In a Profiler trace of the two we can find the metrics we are interested in. CPU and duration are well out but what about reads (210 and 1935)? To save you doing the maths, though you are more than welcome to, that’s a 90.2% / 9.8% split.  Close, but no cigar. Lets try a different tact.  Looking at the execution plan the “Estimated Subtree cost” of query 1 is 0.29449 and query 2 its 1.96596.  Again to save you the maths that works out to 13.03% and 86.97%, round those and thats the figures we are after.  But, what is the worrying word there ? “Estimated”.  So these are not “actual”  execution costs,  but what’s the problem in comparing the estimated costs to derive a meaning of “Most Costly”.  Well, in the case of simple queries such as the above , probably not a lot.  In more complicated queries , a fair bit. By modifying the second query to also show the total number of lines on each order SELECT *,COUNT(*) OVER (PARTITION BY Sales.SalesOrderDetail.SalesOrderID) FROM Sales.SalesOrderDetail JOIN Sales.SalesOrderHeader ON Sales.SalesOrderDetail.SalesOrderID = Sales.SalesOrderHeader.SalesOrderID The split in percentages is now 6% / 94% and the profiler metrics are : Even more of a discrepancy. Estimates can be out with actuals for a whole host of reasons,  scalar UDF’s are a particular bug bear of mine and in-fact the cost of a udf call is entirely hidden inside the execution plan.  It always estimates to 0 (well, a very small number). Take for instance the following udf Create Function dbo.udfSumSalesForCustomer(@CustomerId integer) returns money as begin Declare @Sum money Select @Sum= SUM(SalesOrderHeader.TotalDue) from Sales.SalesOrderHeader where CustomerID = @CustomerId return @Sum end If we have two statements , one that fires the udf and another that doesn't: Select CustomerID from Sales.Customer order by CustomerID go Select CustomerID,dbo.udfSumSalesForCustomer(Customer.CustomerID) from Sales.Customer order by CustomerID The costs relative to batch is a 50/50 split, but the has to be an actual cost of firing the udf. Indeed profiler shows us : No where even remotely near 50/50!!!! Moving forward to window framing functionality in SQL Server 2012 the optimizer sees ROWS and RANGE ( see here for their functional differences) as the same ‘cost’ too SELECT SalesOrderDetailID,SalesOrderId, SUM(LineTotal) OVER(PARTITION BY salesorderid ORDER BY Salesorderdetailid RANGE unbounded preceding) from Sales.SalesOrderdetail go SELECT SalesOrderDetailID,SalesOrderId, SUM(LineTotal) OVER(PARTITION BY salesorderid ORDER BY Salesorderdetailid Rows unbounded preceding) from Sales.SalesOrderdetail By now it wont be a great display to show you the Profiler trace reads a *tiny* bit different. So moral of the story, Percentage relative to batch can give a rough ‘finger in the air’ measurement, but dont rely on it as fact.

  Read the article

• What makes them click ?

  - by Piet

  The other day (well, actually some weeks ago while relaxing at the beach in Kos) I read ‘Neuro Web Design - What makes them click?’ by Susan Weinschenk. (http://neurowebbook.com) The book is a fast and easy read (no unnecessary filler) and a good introduction on how your site’s visitors can be steered in the direction you want them to go. The Obvious The book handles some of the more known/proven techniques, like for example that ratings/testimonials of other people can help sell your product or service. Another well known technique it talks about is inducing a sense of scarcity/urgency in the visitor. Only 2 seats left! Buy now and get 33% off! It’s not because these are known techniques that they stop working. Luckily 2/3rd of the book handles less obvious techniques, otherwise it wouldn’t be worth buying. The Not So Obvious A less known influencing technique is reciprocity. And then I’m not talking about swapping links with another website, but the fact that someone is more likely to do something for you after you did something for them first. The book cites some studies (I always love the facts and figures) and gives some actual examples of how to implement this in your site’s design, which is less obvious when you think about it. Want to know more ? Buy the book! Other interesting sources For a more general introduction to the same principles, I’d suggest ‘Yes! 50 Secrets from the Science of Persuasion’. ‘Yes!…’ cites some of the same studies (it seems there’s a rather limited pool of studies covering this subject), but of course doesn’t show how to implement these techniques in your site’s design. I read ‘Yes!…’ last year, making ‘Neuro Web Design’ just a little bit less interesting. !!!Always make sure you’re able to measure your changes. If you haven’t yet, check out the advanced segmentation in Google Analytics (don’t be afraid because it says ‘beta’, it works just fine) and Google Website Optimizer. Worth Buying? Can I recommend it ? Sure, why not. I think it can be useful for anyone who ever had to think about the design or content of a site. You don’t have to be a marketing guy to want a site you’re involved with to be successful. The content/filler ratio is excellent too: you don’t need to wade through dozens of pages to filter out the interesting bits. (unlike ‘The Design of Sites’, which contains too much useless info and because it’s in dead-tree format, you can’t google it) If you like it, you might also check out ‘Yes! 50 Secrets from the Science of Persuasion’. Tip for people living in Europe: check Amazon UK for your book buying needs. Because of the low UK Pound exchange rate, it’s usually considerably cheaper and faster to get a book delivered to your doorstep by Amazon UK compared to having to order it at the local book store or web-shop.

  Read the article

• SQL SERVER – Guest Post – Glenn Berry – Wait Type – Day 26 of 28

  - by pinaldave

  Glenn Berry works as a Database Architect at NewsGator Technologies in Denver, CO. He is a SQL Server MVP, and has a whole collection of Microsoft certifications, including MCITP, MCDBA, MCSE, MCSD, MCAD, and MCTS. He is also an Adjunct Faculty member at University College – University of Denver, where he has been teaching since 2000. He is one wonderful blogger and often blogs at here. I am big fan of the Dynamic Management Views (DMV) scripts of Glenn. His script are extremely popular and the reality is that he has inspired me to start this series with his famous DMV which I have mentioned in very first  wait stats blog post (I had forgot to request his permission to re-use the script but when asked later on his whole hearty approved it). Here is is his excellent blog post on this subject of wait stats: Analyzing cumulative wait stats in SQL Server 2005 and above has become a popular and effective technique for diagnosing performance issues and further focusing your troubleshooting and diagnostic  efforts.  Rather than just guessing about what resource(s) that SQL Server is waiting on, you can actually find out by running a relatively simple DMV query. Once you know what resources that SQL Server is spending the most time waiting on, you can run more specific queries that focus on that resource to get a better idea what is causing the problem. I do want to throw out a few caveats about using wait stats as a diagnostic tool. First, they are most useful when your SQL Server instance is experiencing performance problems. If your instance is running well, with no indication of any resource pressure from other sources, then you should not worry that much about what the top wait types are. SQL Server will always be waiting on some resource, but many wait types are quite benign, and can be safely ignored. In spite of this, I quite often see experienced DBAs obsessing over the top wait type, even when their SQL Server instance is running extremely well. Second, I often see DBAs jump to the wrong conclusion based on seeing a particular well-known wait type. A good example is CXPACKET waits. People typically jump to the conclusion that high CXPACKET waits means that they should immediately change their instance-level MADOP setting to 1. This is not always the best solution. You need to consider your workload type, and look carefully for any important “missing” indexes that might be causing the query optimizer to use a parallel plan to compensate for the missing index. In this case, correcting the index problem is usually a better solution than changing MAXDOP, since you are curing the disease rather than just treating the symptom. Finally, you should get in the habit of clearing out your cumulative wait stats with the  DBCC SQLPERF(‘sys.dm_os_wait_stats’, CLEAR); command. This is especially important if you have made an configuration or index changes, or if your workload has changed recently. Otherwise, your cumulative wait stats will be polluted with the old stats from weeks or months ago (since the last time SQL Server was started or the stats were cleared).  If you make a change to your SQL Server instance, or add an index, you should clear out your wait stats, and then wait a while to see what your new top wait stats are. At any rate, enjoy Pinal Dave’s series on Wait Stats. This blog post has been written by Glenn Berry (Twitter | Blog) Read all the post in the Wait Types and Queue series. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Pinal Dave, PostADay, Readers Contribution, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQL Wait Stats, SQL Wait Types, T SQL, Technology

  Read the article

• A temporary disagreement

  - by Tony Davis

  Last month, Phil Factor caused a furore amongst some MVPs with an article that attempted to offer simple advice to developers regarding the use of table variables, versus local and global temporary tables, in their code. Phil makes clear that the table variables do come with some fairly major limitations.no distribution statistics, no parallel query plans for queries that modify table variables.but goes on to suggest that for reasonably small-scale strategic uses, and with a bit of due care and testing, table variables are a "good thing". Not everyone shares his opinion; in fact, I imagine he was rather aghast to learn that there were those felt his article was akin to pulling the pin out of a grenade and tossing it into the database; table variables should be avoided in almost all cases, according to their advice, in favour of temp tables. In other words, a fairly major feature of SQL Server should be more-or-less 'off limits' to developers. The problem with temp tables is that, because they are scoped either in the procedure or the connection, it is easy to allow them to hang around for too long, eating up precious memory and bulking up the shared tempdb database. Unless they are explicitly dropped, global temporary tables, and local temporary tables created within a connection rather than within a stored procedure, will persist until the connection is closed or, with connection pooling, until the connection is reused. It's also quite common with ASP.NET applications to have connection leaks, as Bill Vaughn explains in his chapter in the "SQL Server Deep Dives" book, meaning that the web page exits without closing the connection object, maybe due to an error condition. This will then hang around in the heap for what might be hours before picked up by the garbage collector. Table variables are much safer in this regard, since they are batch-scoped and so are cleaned up automatically once the batch is complete, which also means that they are intuitive to use for the developer because they conform to scoping rules that are closer to those in procedural code. On the surface then, an ideal way to deal with issues related to tempdb memory hogging. So why did Phil qualify his recommendation to use Table Variables? This is another of those cases where, like scalar UDFs and table-valued multi-statement UDFs, developers can sometimes get into trouble with a relatively benign-looking feature, due to way it's been implemented in SQL Server. Once again the biggest problem is how they are handled internally, by the SQL Server query optimizer, which can make very poor choices for JOIN orders and so on, in the absence of statistics, especially when joining to tables with highly-skewed data. The resulting execution plans can be horrible, as will be the resulting performance. If the JOIN is to a large table, that will hurt. Ideally, Microsoft would simply fix this issue so that developers can't get burned in this way; they've been around since SQL Server 2000, so Microsoft has had a bit of time to get it right. As I commented in regard to UDFs, when developers discover issues like with such standard features, the database becomes an alien planet to them, where death lurks around each corner, and they continue to avoid these "killer" features years after the problems have been eventually resolved. In the meantime, what is the right approach? Is it to say "hammers can kill, don't ever use hammers", or is it to try to explain, as Phil's article and follow-up blog post have tried to do, what the feature was intended for, why care must be applied in its use, and so enable developers to make properly-informed decisions, without requiring them to delve deep into the inner workings of SQL Server? Cheers, Tony.

  Read the article

< Previous Page | 15 16 17 18 19 20 21 22 23 24 25  | Next Page >