Search Results

Search found 1898 results on 76 pages for 'paul petrov'.

Page 75/76 | < Previous Page | 71 72 73 74 75 76  | Next Page >

• MSCC: Career & IT Fair 2014

  Already a couple of weeks ago, I've been addressed by Ibraahim and Yunus to see whether it would be interesting to participate in the 1st Career & IT Fair organised by the UoM Computer Club. Well, luckily we met at the Global Windows Azure Bootcamp and I wasn't too sure whether it would be possible for me to attend after all. The main reason is given because of work demand and furthermore due to the fact that the Mauritius Software Craftsmanship Community currently has no advertising material at all. Here's the brief statement of the event: "The UOM Students' Computer Club in collaboration with the UOM Students' Union and UOM CSE Department is organising a 'Career & IT Fair' on the 23rd and 24th April 2014. This event has for objective to provide a platform to tertiary students, secondary students as well as vocational students, the opportunity to meet job recruiters." Luckily, I was reminded that the 23rd is a Wednesday, and therefore I decided that it might be interesting to move our weekly Code & Coffee session to the university and hence be able to attend the career fair. As it turned out it was a great choice and thankfully Pritvi, Nadim as well as Ishwon volunteered to be around at the "community booth". Thankfully, the computer club gave us - the MSCC and the LUGM - one of their spaces in the lobby area of the Paul Octave Wiéhé Auditorium. My impression about the event Very well and professionally organised. Seriously, the lads over at the UoM Computer Club did a great job in organising their 2 days event, and felt very comfortable at any time. Actually, it was kind of amusing to some of the members constantly running around and checking everything. Even though that the whole process went smooth and easy off the hand. There were a couple of interesting pieces of information and announcements during the opening ceremony. For example, the Computer Science faculty is a very young one and has been initiated back in 1988 only - just by 4 staff members at that time. Now, after 25 years they have achieved quite a lot and there are currently 1.000+ active students attending the numerous lectures and courses. But there is no room to rest on previous achievements, and I was kind of surprised to hear that there are plans to extend the campus, and offer new lectures in the fields of nanotechnology, big data handling, and - crossing fingers - the introduction and establishment of a space control centre. Mauritius is already part of the Square Kilometre Array (SKA) and hopefully there will be more activities into that direction in the near future. Community - Awareness and collaboration As stated earlier, I could only spent one morning but luckily other members of the MSCC and the LUGM stayed during the whole two days and provided answers to any interested person. As for me, I took the opportunity to get in touch with the other companies in the lobby. Mainly, to create some awareness about our IT communities but also to see whether there might be options for future engagement in common activities, too. So far, I was able to speak to representatives of the following companies: ACCA Mauritius Business at Work Infomil LinkByNet Microsoft Indian Ocean Islands & French Pacific Spherinity Training Institute Spoon Consulting Ltd. State Informatics Ltd. Unfortunately, I only had a quick chat with an HR representative of LinkByNet but I fully count on our MSCC members like Nitin or LUGM member Ronny to spread our intentions over there.  So far, all of the representatives were really interested in our concepts and activities and I'm currently catching up with an introduction flyer for the MSCC that I'm going to send out to all those contacts via mail. It would be great to have more craftsmen as well as professional support on board. Some pictures from the event MSCC: Fantastic outlook for the near future. Announcements were made on Big data, nanotechnology, and space control centre in Mauritius. Interesting! MSCC: The lobby area was cramped with students. Great way to exchange and network. Good luck to all candidates! Passing the relay staff to... I recommend you to continue to read about the first Career & IT Fair on Ish's blog. He has a great summary and more details on those two days of IT activities than I have. Thanks and feel free to leave a comment (or two)... 

  Read the article

• Sort Data in Windows Phone using Collection View Source

  - by psheriff

  When you write a Windows Phone application you will most likely consume data from a web service somewhere. If that service returns data to you in a sort order that you do not want, you have an easy alternative to sort the data without writing any C# or VB code. You use the built-in CollectionViewSource object in XAML to perform the sorting for you. This assumes that you can get the data into a collection that implements the IEnumerable or IList interfaces.For this example, I will be using a simple Product class with two properties, and a list of Product objects using the Generic List class. Try this out by creating a Product class as shown in the following code:public class Product {  public Product(int id, string name)   {    ProductId = id;    ProductName = name;  }  public int ProductId { get; set; }  public string ProductName { get; set; }}Create a collection class that initializes a property called DataCollection with some sample data as shown in the code below:public class Products : List<Product>{  public Products()  {    InitCollection();  }  public List<Product> DataCollection { get; set; }  List<Product> InitCollection()  {    DataCollection = new List<Product>();    DataCollection.Add(new Product(3,        "PDSA .NET Productivity Framework"));    DataCollection.Add(new Product(1,        "Haystack Code Generator for .NET"));    DataCollection.Add(new Product(2,        "Fundamentals of .NET eBook"));    return DataCollection;  }}Notice that the data added to the collection is not in any particular order. Create a Windows Phone page and add two XML namespaces to the Page.xmlns:scm="clr-namespace:System.ComponentModel;assembly=System.Windows"xmlns:local="clr-namespace:WPSortData"The 'local' namespace is an alias to the name of the project that you created (in this case WPSortData). The 'scm' namespace references the System.Windows.dll and is needed for the SortDescription class that you will use for sorting the data. Create a phone:PhoneApplicationPage.Resources section in your Windows Phone page that looks like the following:<phone:PhoneApplicationPage.Resources>  <local:Products x:Key="products" />  <CollectionViewSource x:Key="prodCollection"      Source="{Binding Source={StaticResource products},                       Path=DataCollection}">    <CollectionViewSource.SortDescriptions>      <scm:SortDescription PropertyName="ProductName"                           Direction="Ascending" />    </CollectionViewSource.SortDescriptions>  </CollectionViewSource></phone:PhoneApplicationPage.Resources>The first line of code in the resources section creates an instance of your Products class. The constructor of the Products class calls the InitCollection method which creates three Product objects and adds them to the DataCollection property of the Products class. Once the Products object is instantiated you now add a CollectionViewSource object in XAML using the Products object as the source of the data to this collection. A CollectionViewSource has a SortDescriptions collection that allows you to specify a set of SortDescription objects. Each object can set a PropertyName and a Direction property. As you see in the above code you set the PropertyName equal to the ProductName property of the Product object and tell it to sort in an Ascending direction.All you have to do now is to create a ListBox control and set its ItemsSource property to the CollectionViewSource object. The ListBox displays the data in sorted order by ProductName and you did not have to write any LINQ queries or write other code to sort the data!<ListBox    ItemsSource="{Binding Source={StaticResource prodCollection}}"   DisplayMemberPath="ProductName" />SummaryIn this blog post you learned that you can sort any data without having to change the source code of where the data comes from. Simply feed the data into a CollectionViewSource in XAML and set some sort descriptions in XAML and the rest is done for you! This comes in very handy when you are consuming data from a source where the data is given to you and you do not have control over the sorting.NOTE: You can download this article and many samples like the one shown in this blog entry at my website. http://www.pdsa.com/downloads. Select “Tips and Tricks”, then “Sort Data in Windows Phone using Collection View Source” from the drop down list.Good Luck with your Coding,Paul Sheriff** SPECIAL OFFER FOR MY BLOG READERS **We frequently offer a FREE gift for readers of my blog. Visit http://www.pdsa.com/Event/Blog for your FREE gift!

  Read the article

• Where Facebook Stands Heading Into 2013

  - by Mike Stiles

  In our last blog, we looked at how Twitter is positioned heading into 2013. Now it’s time to take a similar look at Facebook. 2012, for a time at least, seemed to be the era of Facebook-bashing. Between a far-from-smooth IPO, subsequent stock price declines, and anxiety over privacy, the top social network became a target for comedians, politicians, business journalists, and of course those who were prone to Facebook-bash even in the best of times. But amidst the “this is the end of Facebook” headlines, the company kept experimenting, kept testing, kept innovating, and pressing forward, committed as always to the user experience, while concurrently addressing monetization with greater urgency. Facebook enters 2013 with over 1 billion users around the world. Usage grew 41% in Brazil, Russia, Japan, South Korea and India in 2012. In the Middle East and North Africa, an average 21 new signups happen per minute. Engagement and time spent on the site would impress the harshest of critics. Facebook, while not bulletproof, has become such an integrated daily force in users’ lives, it’s getting hard to imagine any future mass rejection. You want to see a company recognizing weaknesses and shoring them up. Mobile was a weakness in 2012 as Facebook was one of many caught by surprise at the speed of user migration to mobile. But new mobile interfaces, better mobile ads, speed upgrades, standalone Messenger and Pages mobile apps, and the big dollar acquisition of Instagram, were a few indicators Facebook won’t play catch-up any more than it has to. As a user, the cool thing about Facebook is, it knows you. The uncool thing about Facebook is, it knows you. The company’s walking a delicate line between the public’s competing desires for customized experiences and privacy. While the company’s working to make privacy options clearer and easier, Facebook’s Paul Adams says data aggregation can move from acting on what a user is engaging with at the moment to a more holistic view of what they’re likely to want at any given time. To help learn about you, there’s Open Graph. Embedded through diverse partnerships, the idea is to surface what you’re doing and what you care about, and help you discover things via your friends’ activities. Facebook’s Director of Engineering, Mike Vernal, says building mobile social apps connected to Facebook in such ways is the next wave of big innovation. Expect to see that fostered in 2013. The Facebook site experience is always evolving. Some users like that about Facebook, others can’t wait to complain about it…on Facebook. The Facebook focal point, the News Feed, is not sacred and is seeing plenty of experimentation with the insertion of modules. From upcoming concerts, events, suggested Pages you might like, to aggregated “most shared” content from social reader apps, plenty could start popping up between those pictures of what your friends had for lunch.  As for which friends’ lunches you see, that’s a function of the mythic EdgeRank…which is also tinkered with. When Facebook changed it in September, Page admins saw reach go down and the high anxiety set in quickly. Engagement, however, held steady. The adjustment was about relevancy over reach. (And oh yeah, reach was something that could be charged for). Facebook wants users to see what they’re most likely to like, based on past usage and interactions. Adding to the “cream must rise to the top” philosophy, they’re now even trying out ordering post comments based on the engagement the comments get. Boy, it’s getting competitive out there for a social engager. Facebook has to make $$$. To do that, they must offer attractive vehicles to marketers. There are a myriad of ad units. But a key Facebook marketing concept is the Sponsored Story. It’s key because it encourages content that’s good, relevant, and performs well organically. If it is, marketing dollars can amplify it and extend its reach. Brands can expect the rollout of a search product and an ad network. That’s a big deal. It takes, as Open Graph does, the power of Facebook’s user data and carries it beyond the Facebook environment into the digital world at large. No one could target like Facebook can, and some analysts think it could double their roughly $5 billion revenue stream. As every potential revenue nook and cranny is explored, there are the users themselves. In addition to Gifts, Facebook thinks users might pay a few bucks to promote their own posts so more of their friends will see them. There’s also word classifieds could be purchased in News Feeds, though they won’t be called classifieds. And that’s where Facebook stands; a wildly popular destination, a part of our culture, with ever increasing functionalities, the biggest of big data, revenue strategies that appeal to marketers without souring the user experience, new challenges as a now public company, ongoing privacy concerns, and innovations that carry Facebook far beyond its own borders. Anyone care to write a “this is the end of Facebook” headline? @mikestilesPhoto via stock.schng

  Read the article

• Best Method For Evaluating Existing Software or New Software

  How many of us have been faced with having to decide on an off-the-self or a custom built component, application, or solution to integrate in to an existing system or to be the core foundation of a new system? What is the best method for evaluating existing software or new software still in the design phase? One of the industry preferred methodologies to use is the Active Reviews for Intermediate Designs (ARID) evaluation process.  ARID is a hybrid mixture of the Active Design Review (ADR) methodology and the Architectural Tradeoff Analysis Method (ATAM). So what is ARID? ARD’s main goal is to ensure quality, detailed designs in software. One way in which it does this is by empowering reviewers by assigning generic open ended survey questions. This approach attempts to remove the possibility for allowing the standard answers such as “Yes” or “No”. The ADR process ignores the “Yes”/”No” questions due to the fact that they can be leading based on how the question is asked. Additionally these questions tend to receive less thought in comparison to more open ended questions. Common Active Design Review Questions What possible exceptions can occur in this component, application, or solution? How should exceptions be handled in this component, application, or solution? Where should exceptions be handled in this component, application, or solution? How should the component, application, or solution flow based on the design? What is the maximum execution time for every component, application, or solution? What environments can this component, application, or solution? What data dependencies does this component, application, or solution have? What kind of data does this component, application, or solution require? Ok, now I know what ARID is, how can I apply? Let’s imagine that your organization is going to purchase an off-the-shelf (OTS) solution for its customer-relationship management software. What process would we use to ensure that the correct purchase is made? If we use ARID, then we will have a series of 9 steps broken up by 2 phases in order to ensure that the correct OTS solution is purchases. Phase 1 Identify the Reviewers Prepare the Design Briefing Prepare the Seed Scenarios Prepare the Materials When identifying reviewers for a design it is preferred that they be pulled from a candidate pool comprised of developers that are going to implement the design. The believe is that developers actually implementing the design will have more a vested interest in ensuring that the design is correct prior to the start of code. Design debriefing consist of a summary of the design, examples of the design solving real world examples put in to use and should be no longer than two hours typically. The primary goal of this briefing is to adequately summarize the design so that the review members could actually implement the design. In the example of purchasing an OTS product I would attempt to review my briefing prior to its distribution with the review facilitator to ensure that nothing was excluded that should have not been. This practice will also allow me to test the length of the briefing to ensure that can be delivered in an appropriate about of time. Seed Scenarios are designed to illustrate conceptualized scenarios when applied with a set of sample data. These scenarios can then be used by the reviewers in the actual evaluation of the software, All materials needed for the evaluation should be prepared ahead of time so that they can be reviewed prior to and during the meeting. Materials Included: Presentation Seed Scenarios Review Agenda Phase 2 Present ARID Present Design Brainstorm and prioritize scenarios Apply scenarios Summarize Prior to the start of any ARID review meeting the Facilitator should define the remaining steps of ARID so that all the participants know exactly what they are doing prior to the start of the review process. Once the ARID rules have been laid out, then the lead designer presents an overview of the design which typically takes about two hours. During this time no questions about the design or rational are allowed to be asked by the review panel as a standard, but they are written down for use latter in the process. After the presentation the list of compiled questions is then summarized and sent back to the lead designer as areas that need to be addressed further. In the example of purchasing an OTS product issues could arise regarding security, the implementation needed or even if this is this the correct product to solve the needed solution. After the Design presentation a brainstorming and prioritize scenarios process begins by reducing the seed scenarios down to just the highest priority scenarios.  These will then be used to test the design for suitability. Once the selected scenarios have been defined the reviewers apply the examples provided in the presentation to the scenarios. The intended output of this process is to provide code or pseudo code that makes use of the examples provided while solving the selected seed scenarios. As a standard rule, the designers of the systems are not allowed to help the review board unless they all become stuck. When this occurs it is documented and along with the reason why the designer needed to help the review panel back on track. Once all of the scenarios have been completed the review facilitator reviews with the group issues that arise during the process. Then the reviewers will be polled as to efficacy of the review experience. References: Clements, Paul., Kazman, Rick., Klien, Mark. (2002). Evaluating Software Architectures: Methods and Case Studies Indianapolis, IN: Addison-Wesley

  Read the article

• How Important is Project Team Communication in the Public Sector?

  - by Melissa Centurio Lopes

  Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* 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:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; 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;} Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* 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:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; 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;} By Paul Bender, Director of Public Administration Strategy, Oracle Primavera It goes without saying that communication between project team members is a core competency that connects every member of a project team to a common set of strategies, goals and actions. If these components are not effectively shared by project leads and understood by stakeholders, project outcomes can be jeopardized and budgets may incur unnecessary risk. As reported by PMI’s 2013 Pulse of the Profession, an organization’s ability to meet project timelines, budgets and especially goals significantly impacts its ability to survive—and even thrive. The Pulse study revealed that the most crucial success factor in project management is effective communication to all stakeholders—a critical core competency for public agencies. PMI’s 2013 Pulse of the Profession report revealed that US$135 million is at risk for every US$1 billion spent on a project. Further research on the importance of effective project team communication uncovers that a startling 56 percent (US$75 million of that US$135 million) is at risk due to ineffective communication. Simply stated: public agencies cannot execute strategic initiatives unless they can effectively communicate their strategic alignment and business benefits. Executives and project managers around the world agree that poor communication between project team members contributes to project failure. A Forbes Insights 2010 Strategic Initiatives Study “Adapting Corporate Strategy to the Changing Economy,” found that nine out of ten CEOs believe that communication is critical to the success of their strategic initiatives, and nearly half of respondents cite communication as an integral and active component of their strategic planning and execution process. Project managers see it similarly from their side as well. According to PMI’s Pulse research, 55 percent of project managers agree that effective communication to all stakeholders is the most critical success factor in project management. As we all know, not all projects succeed. On average, two in five projects do not meet their original goals and business intent, and one-half of those unsuccessful projects are related to ineffective communication. Results reveal that while all aspects of project communication can be challenging to public agencies, the biggest problem areas are: A gap in understanding the business benefits. Challenges surrounding the language used to deliver project-related information, which is often unclear and peppered with project management jargon. Public agencies -- federal, state, and local -- have difficulty communicating with the appropriate levels with clarity and detail. This difficulty is likely exacerbated by the divide between each key audience and its understanding of project-specific, technical language. For those involved in public sector project and portfolio management, I would be interested to hear your thoughts and please visit Primavera EPPM solutions for public sector.

  Read the article

• VB.Net Dynamically Load DLL

  - by hermiod

  I am trying to write some code that will allow me to dynamically load DLLs into my application, depending on an application setting. The idea is that the database to be accessed is set in the application settings and then this loads the appropriate DLL and assigns it to an instance of an interface for my application to access. This is my code at the moment: Dim SQLDataSource As ICRDataLayer Dim ass As Assembly = Assembly. _ LoadFrom("M:\MyProgs\WebService\DynamicAssemblyLoading\SQLServer\bin\Debug\SQLServer.dll") Dim obj As Object = ass.CreateInstance(GetType(ICRDataLayer).ToString, True) SQLDataSource = DirectCast(obj, ICRDataLayer) MsgBox(SQLDataSource.ModuleName & vbNewLine & SQLDataSource.ModuleDescription) I have my interface (ICRDataLayer) and the SQLServer.dll contains an implementation of this interface. I just want to load the assembly and assign it to the SQLDataSource object. The above code just doesn't work. There are no exceptions thrown, even the Msgbox doesn't appear. I would've expected at least the messagebox appearing with nothing in it, but even this doesn't happen! Is there a way to determine if the loaded assembly implements a specific interface. I tried the below but this also doesn't seem to do anything! For Each loadedType As Type In ass.GetTypes If GetType(ICRDataLayer).IsAssignableFrom(loadedType) Then Dim obj1 As Object = ass.CreateInstance(GetType(ICRDataLayer).ToString, True) SQLDataSource = DirectCast(obj1, ICRDataLayer) End If Next EDIT: New code from Vlad's examples: Module CRDataLayerFactory Sub New() End Sub ' class name is a contract, ' should be the same for all plugins Private Function Create() As ICRDataLayer Return New SQLServer() End Function End Module Above is Module in each DLL, converted from Vlad's C# example. Below is my code to bring in the DLL: Dim SQLDataSource As ICRDataLayer Dim ass As Assembly = Assembly. _ LoadFrom("M:\MyProgs\WebService\DynamicAssemblyLoading\SQLServer\bin\Debug\SQLServer.dll") Dim factory As Object = ass.CreateInstance("CRDataLayerFactory", True) Dim t As Type = factory.GetType Dim method As MethodInfo = t.GetMethod("Create") Dim obj As Object = method.Invoke(factory, Nothing) SQLDataSource = DirectCast(obj, ICRDataLayer) EDIT: Implementation based on Paul Kohler's code Dim file As String For Each file In Directory.GetFiles(baseDir, searchPattern, SearchOption.TopDirectoryOnly) Dim assemblyType As System.Type For Each assemblyType In Assembly.LoadFrom(file).GetTypes Dim s As System.Type() = assemblyType.GetInterfaces For Each ty As System.Type In s If ty.Name.Contains("ICRDataLayer") Then MsgBox(ty.Name) plugin = DirectCast(Activator.CreateInstance(assemblyType), ICRDataLayer) MessageBox.Show(plugin.ModuleName) End If Next I get the following error with this code: Unable to cast object of type 'SQLServer.CRDataSource.SQLServer' to type 'DynamicAssemblyLoading.ICRDataLayer'. The actual DLL is in a different project called SQLServer in the same solution as my implementation code. CRDataSource is a namespace and SQLServer is the actual class name of the DLL. The SQLServer class implements ICRDataLayer, so I don't understand why it wouldn't be able to cast it. Is the naming significant here, I wouldn't have thought it would be.

  Read the article

• *UPDATED* help with django and accented characters?

  - by Asinox

  Hi guys, i have a problem with my accented characters, Django admin save my data without encoding to something like "&aacute;" Example: if im trying a word like " Canción ", i would like to save in this way: Canci&oacute;n, and not Canción. im usign Sociable app: {% load sociable_tags %} {% get_sociable Facebook TwitThis Google MySpace del.icio.us YahooBuzz Live as sociable_links with url=object.get_absolute_url title=object.titulo %} {% for link in sociable_links %} <a href="{{ link.link }}"><img alt="{{ link.site }}" title="{{ link.site }}" src="{{ link.image }}" /></a> {% endfor %} But im getting error if my object.titulo (title of the article) have a accented word. aught KeyError while rendering: u'\xfa' Any idea ? i had in my SETTING: DEFAULT_CHARSET = 'utf-8' i had in my mysql database: utf8_general_ci COMPLETED ERROR: Traceback: File "C:\wamp\bin\Python26\lib\site-packages\django\core\handlers\base.py" in get_response 100. response = callback(request, *callback_args, **callback_kwargs) File "C:\wamp\bin\Python26\lib\site-packages\django\views\generic\date_based.py" in object_detail 366. response = HttpResponse(t.render(c), mimetype=mimetype) File "C:\wamp\bin\Python26\lib\site-packages\django\template\__init__.py" in render 173. return self._render(context) File "C:\wamp\bin\Python26\lib\site-packages\django\template\__init__.py" in _render 167. return self.nodelist.render(context) File "C:\wamp\bin\Python26\lib\site-packages\django\template\__init__.py" in render 796. bits.append(self.render_node(node, context)) File "C:\wamp\bin\Python26\lib\site-packages\django\template\debug.py" in render_node 72. result = node.render(context) File "C:\wamp\bin\Python26\lib\site-packages\django\template\loader_tags.py" in render 125. return compiled_parent._render(context) File "C:\wamp\bin\Python26\lib\site-packages\django\template\__init__.py" in _render 167. return self.nodelist.render(context) File "C:\wamp\bin\Python26\lib\site-packages\django\template\__init__.py" in render 796. bits.append(self.render_node(node, context)) File "C:\wamp\bin\Python26\lib\site-packages\django\template\debug.py" in render_node 72. result = node.render(context) File "C:\wamp\bin\Python26\lib\site-packages\django\template\loader_tags.py" in render 62. result = block.nodelist.render(context) File "C:\wamp\bin\Python26\lib\site-packages\django\template\__init__.py" in render 796. bits.append(self.render_node(node, context)) File "C:\wamp\bin\Python26\lib\site-packages\django\template\debug.py" in render_node 72. result = node.render(context) File "C:\wamp\bin\Python26\lib\site-packages\sociable\templatetags\sociable_tags.py" in render 37. 'link': sociable.genlink(site, **self.values), File "C:\wamp\bin\Python26\lib\site-packages\sociable\sociable.py" in genlink 20. values['title'] = quote_plus(kwargs['title']) File "C:\wamp\bin\Python26\lib\urllib.py" in quote_plus 1228. s = quote(s, safe + ' ') File "C:\wamp\bin\Python26\lib\urllib.py" in quote 1222. res = map(safe_map.__getitem__, s) Exception Type: TemplateSyntaxError at /noticia/2010/jun/10/matan-domingo-paquete-en-la-avenida-san-vicente-de-paul/ Exception Value: Caught KeyError while rendering: u'\xfa' thanks, sorry with my English

  Read the article

• List of freely available programming books

  - by Karan Bhangui

  I'm trying to amass a list of programming books with opensource licenses, like Creative Commons, GPL, etc. The books can be about a particular programming language or about computers in general. Hoping you guys could help: Languages BASH Advanced Bash-Scripting Guide (An in-depth exploration of the art of shell scripting) C The C book C++ Thinking in C++ C++ Annotations How to Think Like a Computer Scientist C# .NET Book Zero: What the C or C++ Programmer Needs to Know About C# and the .NET Framework Illustrated C# 2008 (Dead Link) Data Structures and Algorithms with Object-Oriented Design Patterns in C# Threading in C# Common Lisp Practical Common Lisp On Lisp Java Thinking in Java How to Think Like a Computer Scientist Java Thin-Client Programming JavaScript Eloquent JavaScript Haskell Real world Haskell Learn You a Haskell for Great Good! Objective-C The Objective-C Programming Language Perl Extreme Perl (license not specified - home page is saying "freely available") The Mason Book (Open Publication License) Practical mod_perl (CreativeCommons Attribution Share-Alike License) Higher-Order Perl Learning Perl the Hard Way PHP Practical PHP Programming Zend Framework: Survive the Deep End PowerShell Mastering PowerShell Prolog Building Expert Systems in Prolog Adventure in Prolog Prolog Programming A First Course Logic, Programming and Prolog (2ed) Introduction to Prolog for Mathematicians Learn Prolog Now! Natural Language Processing Techniques in Prolog Python Dive Into Python Dive Into Python 3 How to Think Like a Computer Scientist A Byte of Python Python for Fun Invent Your Own Computer Games With Python Ruby Why's (Poignant) Guide to Ruby Programming Ruby - The Pragmatic Programmer's Guide Mr. Neighborly's Humble Little Ruby Book SQL Practical PostgreSQL x86 assembly Paul Carter's tutorial Lua Programming In Lua (for v5 but still largely relevant) Algorithms and Data Structures Algorithms Data Structures and Algorithms with Object-Oriented Design Patterns in Java Planning Algorithms Frameworks/Projects The Django Book The Pylons Book Introduction to Design Patterns in C++ with Qt 4 (Open Publication License) Version control The SVN Book Mercurial: The Definitive Guide Pro Git UNIX / Linux The Art of Unix Programming Linux Device Drivers, Third Edition Others Structure and Interpretation of Computer Programs The Little Book of Semaphores Mathematical Logic - an Introduction An Introduction to the Theory of Computation Developers Developers Developers Developers Linkers and loaders Beej's Guide to Network Programming Maven: The Definitive Guide I will expand on this list as I get comments or when I think of more :D Related: Programming texts and reference material for my Kindle What are some good free programming books? Can anyone recommend a free software engineering book? Edit: Oh I didn't notice the community wiki feature. Feel free to edit your suggestions right in!

  Read the article

• Nhibernate One-to-one mapping issue with child object insert error

  - by TalkDotNet

  Hi, i've being banging my head against the desk all day with the following Nhibernate problem. Each bank account has one (and only one) set of rates associated with it. The primary key of the bank account table, BankAccountID is also a foreign key and the primary key in the rates table. public class BankAccount { public virtual int BankAccountId { get; set; } public virtual string AccountName { get; set;} public virtual AccountRate AccountRate {get;set;} } public class AccountRate { public virtual int BankAccountId { get; set; } public virtual decimal Rate1 { get; set; } public virtual decimal Rate2 { get; set; } } I have the following HBM mappings for BankAccount: <class name="BankAccount" table="BankAccount"> <id name ="BankAccountId" column="BankAccountId"> <generator class="foreign"> <param name="property"> AccountRate </param> </generator> </id> <property name ="AccountName" column="AccountName" /> <one-to-one name="AccountRate" class="AccountRate" constrained="true" cascade="save-update"/> </class> and the following for AccountRate: <class name="AccountRate" table="AccountRate"> <id name ="BankAccountId" column="BankAccountId"> <generator class="native" /> </id> <property name ="Rate1" column="Rate1" /> <property name ="Rate2" column="Rate2" /> </class> An existing BankAccount object can be read from the database with no problem. However, when a new BankAccount is created , the insert statement fails with; Cannot insert the value NULL into column 'BankAccountId' The issue appears to be that the child object , AccountRate is created first and since it hasn't yet got an identifier from its uncreated parent , the insert fails. I think i'm correct in saying that if the AccountRate property on BankAccount was a collection i could use the following ? Inverse=True in order to force the parent to be inserted first. Can anyone help me with this? i Really dont want to use a collection as there is only a unidirectional one to one relationship between these tables. Thanks Paul

  Read the article

• How to setup a webserver in common lisp?

  - by Serpico

  Several months ago, I was inspired by the magnificent book ANSI Common Lisp written by Paul Graham, and the statement that Lisp could be used as a secret weapon in your web development, published by the same author on his blog. Wow, that is amazing. That is something that I have been looking for long time. The author really developed a successful web applcation and sold it to Yahoo. With those encouraging images, I determined to spend some time (1 year or 2 year, who knows) on learning Common Lisp. Maybe someday I will development my web application and turn into a great Lisp expert. In fact, this is the second time for me to get to study Lisp. The first time was a couple of years ago when I was fascinated by the famous book SICP but found later Scheme was so unbelievably immature for real life application. After reading some chapters of ANSI Common Lisp, I was pretty sure that is a great book full of detailed exploration of Common Lisp. Then I began to set up a web server in Common Lisp. After all, this should be the best way if you want to learn something. Demonstrations are always better than definations. As suggested by the book Practical Common Lisp (by the way, this is also a great book), I chose to install AllegroServe on some Common Lisp implementation. Then, from somewhere else, I learned that Hunchentoot seems to be better than AllegroServe. (I don't remember where and whom this word is from. So don't argue with me.) Ironically, you know what, I never could installed the two packages on any Common Lisp implementation. More annoyingly, I even don't know why. The machine always spit up a lot of jargon and lead me into a chaos. I've tried searching the internet and have not found anything. Could anybody who has successfully installed these packages in Linux tell me how you did it? Have you run into any trouble? How did you figured out what is wrong and fixed it? The more detailed, the more helpful.

  Read the article

• .Net Dynamically Load DLL

  - by hermiod

  I am trying to write some code that will allow me to dynamically load DLLs into my application, depending on an application setting. The idea is that the database to be accessed is set in the application settings and then this loads the appropriate DLL and assigns it to an instance of an interface for my application to access. This is my code at the moment: Dim SQLDataSource As ICRDataLayer Dim ass As Assembly = Assembly. _ LoadFrom("M:\MyProgs\WebService\DynamicAssemblyLoading\SQLServer\bin\Debug\SQLServer.dll") Dim obj As Object = ass.CreateInstance(GetType(ICRDataLayer).ToString, True) SQLDataSource = DirectCast(obj, ICRDataLayer) MsgBox(SQLDataSource.ModuleName & vbNewLine & SQLDataSource.ModuleDescription) I have my interface (ICRDataLayer) and the SQLServer.dll contains an implementation of this interface. I just want to load the assembly and assign it to the SQLDataSource object. The above code just doesn't work. There are no exceptions thrown, even the Msgbox doesn't appear. I would've expected at least the messagebox appearing with nothing in it, but even this doesn't happen! Is there a way to determine if the loaded assembly implements a specific interface. I tried the below but this also doesn't seem to do anything! For Each loadedType As Type In ass.GetTypes If GetType(ICRDataLayer).IsAssignableFrom(loadedType) Then Dim obj1 As Object = ass.CreateInstance(GetType(ICRDataLayer).ToString, True) SQLDataSource = DirectCast(obj1, ICRDataLayer) End If Next EDIT: New code from Vlad's examples: Module CRDataLayerFactory Sub New() End Sub ' class name is a contract, ' should be the same for all plugins Private Function Create() As ICRDataLayer Return New SQLServer() End Function End Module Above is Module in each DLL, converted from Vlad's C# example. Below is my code to bring in the DLL: Dim SQLDataSource As ICRDataLayer Dim ass As Assembly = Assembly. _ LoadFrom("M:\MyProgs\WebService\DynamicAssemblyLoading\SQLServer\bin\Debug\SQLServer.dll") Dim factory As Object = ass.CreateInstance("CRDataLayerFactory", True) Dim t As Type = factory.GetType Dim method As MethodInfo = t.GetMethod("Create") Dim obj As Object = method.Invoke(factory, Nothing) SQLDataSource = DirectCast(obj, ICRDataLayer) EDIT: Implementation based on Paul Kohler's code Dim file As String For Each file In Directory.GetFiles(baseDir, searchPattern, SearchOption.TopDirectoryOnly) Dim assemblyType As System.Type For Each assemblyType In Assembly.LoadFrom(file).GetTypes Dim s As System.Type() = assemblyType.GetInterfaces For Each ty As System.Type In s If ty.Name.Contains("ICRDataLayer") Then MsgBox(ty.Name) plugin = DirectCast(Activator.CreateInstance(assemblyType), ICRDataLayer) MessageBox.Show(plugin.ModuleName) End If Next I get the following error with this code: Unable to cast object of type 'SQLServer.CRDataSource.SQLServer' to type 'DynamicAssemblyLoading.ICRDataLayer'. The actual DLL is in a different project called SQLServer in the same solution as my implementation code. CRDataSource is a namespace and SQLServer is the actual class name of the DLL. The SQLServer class implements ICRDataLayer, so I don't understand why it wouldn't be able to cast it. Is the naming significant here, I wouldn't have thought it would be.

  Read the article

• Is there a scheduling algorithm that optimizes for "maker's schedules"?

  - by John Feminella

  You may be familiar with Paul Graham's essay, "Maker's Schedule, Manager's Schedule". The crux of the essay is that for creative and technical professionals, meetings are anathema to productivity, because they tend to lead to "schedule fragmentation", breaking up free time into chunks that are too small to acquire the focus needed to solve difficult problems. In my firm we've seen significant benefits by minimizing the amount of disruption caused, but the brute-force algorithm we use to decide schedules is not sophisticated enough to handle scheduling large groups of people well. (*) What I'm looking for is if there's are any well-known algorithms which minimize this productivity disruption, among a group of N makers and managers. In our model, There are N people. Each person pi is either a maker (Mk) or a manager (Mg). Each person has a schedule si. Everyone's schedule is H hours long. A schedule consists of a series of non-overlapping intervals si = [h1, ..., hj]. An interval is either free or busy. Two adjacent free intervals are equivalent to a single free interval that spans both. A maker's productivity is maximized when the number of free intervals is minimized. A manager's productivity is maximized when the total length of free intervals is maximized. Notice that if there are no meetings, both the makers and the managers experience optimum productivity. If meetings must be scheduled, then makers prefer that meetings happen back-to-back, while managers don't care where the meeting goes. Note that because all disruptions are treated as equally harmful to makers, there's no difference between a meeting that lasts 1 second and a meeting that lasts 3 hours if it segments the available free time. The problem is to decide how to schedule M different meetings involving arbitrary numbers of the N people, where each person in a given meeting must place a busy interval into their schedule such that it doesn't overlap with any other busy interval. For each meeting Mt the start time for the busy interval must be the same for all parties. Does an algorithm exist to solve this problem or one similar to it? My first thought was that this looks really similar to defragmentation (minimize number of distinct chunks), and there are a lot of algorithms about that. But defragmentation doesn't have much to do with scheduling. Thoughts? (*) Practically speaking this is not really a problem, because it's rare that we have meetings with more than ~5 people at once, so the space of possibilities is small.

  Read the article

• Why am I unable to telnet to a local port that has a listening service?

  - by Skip Huffman

  I suspect this is either a very simple question, or a very complex one. I have a headless server running ubuntu 10.04 that I can ssh into. I have full root access to the system. I am trying to set up an ssh tunnel to allow me to vnc to the system (but that isn't my question. I have vnc running on port 5903, here is the netstat output for that: Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 0.0.0.0:5903 0.0.0.0:* LISTEN 7173/Xtightvnc tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 465/sshd But when I try to telnet to that port, from within the same system and login, I get unable to connect errors # telnet localhost 5903 Trying ::1... Trying 127.0.0.1... telnet: Unable to connect to remote host: Connection timed out I am able to telnet to port 22 (as a verification) ~# telnet localhost 22 Trying ::1... Connected to localhost. Escape character is '^]'. SSH-2.0-OpenSSH_5.3p1 Debian-3ubuntu7 I have tried to open up any possible ports using ufw (probably clumsy fashion) # ufw status numbered Status: active To Action From -- ------ ---- [ 1] 5903 ALLOW IN Anywhere [ 2] 22 ALLOW IN Anywhere What else might be blocking this connection locally? Thank you, Edit: The only reference to port 5903 in iptable -L -n is this: Chain ufw-user-input (1 references) target prot opt source destination ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:5903 ACCEPT udp -- 0.0.0.0/0 0.0.0.0/0 udp dpt:5903 ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:22 ACCEPT udp -- 0.0.0.0/0 0.0.0.0/0 udp dpt:22 ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:8080 ACCEPT udp -- 0.0.0.0/0 0.0.0.0/0 udp dpt:8080 I can post the whole output if that will be useful. hosts.allow and hosts.deny both contain only comments. Re-Edit: Some other questions pointed me to nmap, so I ran a portscan through that utility: # nmap -v -sT localhost -p1-65535 Starting Nmap 5.00 ( http://nmap.org ) at 2011-11-09 09:58 PST NSE: Loaded 0 scripts for scanning. Warning: Hostname localhost resolves to 2 IPs. Using 127.0.0.1. Initiating Connect Scan at 09:58 Scanning localhost (127.0.0.1) [65535 ports] Discovered open port 22/tcp on 127.0.0.1 Connect Scan Timing: About 18.56% done; ETC: 10:01 (0:02:16 remaining) Connect Scan Timing: About 44.35% done; ETC: 10:00 (0:01:17 remaining) Completed Connect Scan at 10:00, 112.36s elapsed (65535 total ports) Host localhost (127.0.0.1) is up (0.00s latency). Interesting ports on localhost (127.0.0.1): Not shown: 65533 filtered ports PORT STATE SERVICE 22/tcp open ssh 80/tcp closed http Read data files from: /usr/share/nmap Nmap done: 1 IP address (1 host up) scanned in 112.43 seconds Raw packets sent: 0 (0B) | Rcvd: 0 (0B) I think this shows that 5903 is blocked somehow. Which I pretty much knew. The question remains what is blocking it and how to modify. Re-re-edit: To check Paul Lathrop's suggested answer, I first verified my ip address with ifconfig: eth0 Link encap:Ethernet HWaddr 02:16:3e:42:28:8f inet addr:10.0.10.3 Bcast:10.0.10.255 Mask:255.255.255.0 Then tried to telnet to 5903 from that address: # telnet 10.0.10.3 5903 Trying 10.0.10.3... telnet: Unable to connect to remote host: Connection timed out No luck. Re-re-re-re-edit: Ok, I think I have isolated it a bit to vncserver, not the firewall, darn it. I shut off vncserver and had netcat listen on port 5903. My vnc client then was able to establish a connnection and sit and wait for a response. Looks like I should be chasing a vnc problem. At least that is progress Thanks for the help

  Read the article

• Issue 15: The Benefits of Oracle Exastack

  - by rituchhibber

       SOLUTIONS FOCUS The Benefits of Oracle Exastack Paul ThompsonDirector, Alliances and Solutions Partner ProgramsOracle EMEA Alliances & Channels RESOURCES -- Oracle PartnerNetwork (OPN) Oracle Exastack Program Oracle Exastack Ready Oracle Exastack Optimized Oracle Exastack Labs and Enablement Resources Oracle Exastack Labs Video Tour SUBSCRIBE FEEDBACK PREVIOUS ISSUES Exastack is a revolutionary programme supporting Oracle independent software vendor partners across the entire Oracle technology stack. Oracle's core strategy is to engineer software and hardware together, and our ISV strategy is the same. At Oracle we design engineered systems that are pre-integrated to reduce the cost and complexity of IT infrastructures while increasing productivity and performance. Oracle innovates and optimises performance at every layer of the stack to simplify business operations, drive down costs and accelerate business innovation. Our engineered systems are optimised to achieve enterprise performance levels that are unmatched in the industry. Faster time to production is achieved by implementing pre-engineered and pre-assembled hardware and software bundles. Our strategy of delivering a single-vendor stack simplifies and reduces costs associated with purchasing, deploying, and supporting IT environments for our customers and partners. In parallel to this core engineered systems strategy, the Oracle Exastack Program enables our Oracle ISV partners to leverage a scalable, integrated infrastructure that delivers their applications tuned, tested and optimised for high-performance. Specifically, the Oracle Exastack Program helps ISVs run their solutions on the Oracle Exadata Database Machine, Oracle Exalogic Elastic Cloud, and Oracle SPARC SuperCluster T4-4 - integrated systems products in which the software and hardware are engineered to work together. These products provide OPN members with a lower cost and high performance infrastructure for database and application workloads across on-premise and cloud based environments. Ready and Optimized Oracle Partners can now leverage our new Oracle Exastack Program to become Oracle Exastack Ready and Oracle Exastack Optimized. Partners can achieve Oracle Exastack Ready status through their support for Oracle Solaris, Oracle Linux, Oracle VM, Oracle Database, Oracle WebLogic Server, Oracle Exadata Database Machine, Oracle Exalogic Elastic Cloud, and Oracle SPARC SuperCluster T4-4. By doing this, partners can demonstrate to their customers that their applications are available on the latest major releases of these products. The Oracle Exastack Ready programme helps customers readily differentiate Oracle partners from lesser software developers, and identify applications that support Oracle engineered systems. Achieving Oracle Exastack Optimized status demonstrates that an OPN member has proven itself against goals for performance and scalability on Oracle integrated systems. This status enables end customers to readily identify Oracle partners that have tested and tuned their solutions for optimum performance on an Oracle Exadata Database Machine, Oracle Exalogic Elastic Cloud, and Oracle SPARC SuperCluster T4-4. These ISVs can display the Oracle Exadata Optimized, Oracle Exalogic Optimized or Oracle SPARC SuperCluster Optimized logos on websites and on all their collateral to show that they have tested and tuned their application for optimum performance. Deliver higher value to customers Oracle's investment in engineered systems enables ISV partners to deliver higher value to customer business processes. New innovations are enabled through extreme performance unachievable through traditional best-of-breed multi-vendor server/software approaches. Core product requirements can be launched faster, enabling ISVs to focus research and development investment on core competencies in order to bring value to market as quickly as possible. Through Exastack, partners no longer have to worry about the underlying product stack, which allows greater focus on the development of intellectual property above the stack. Partners are not burdened by platform issues and can concentrate simply on furthering their applications. The advantage to end customers is that partners can focus all efforts on business functionality, rather than bullet-proofing underlying technologies, and so will inevitably deliver application updates faster. Exastack provides ISVs with a number of flexible deployment options, such as on-premise or Cloud, while maintaining one single code base for applications regardless of customer deployment preference. Customers buying their solutions from Exastack ISVs can therefore be confident in deploying on their own networks, on private clouds or into a public cloud. The underlying platform will support all conceivable deployments, enabling a focus on the ISV's application itself that wouldn't be possible with other vendor partners. It stands to reason that Exastack accelerates time to value as well as lowering implementation costs all round. There is a big competitive advantage in partners being able to offer customers an optimised, pre-configured solution rather than an assortment of components and a suggested fit. Once a customer has decided to buy an Oracle Exastack Ready or Optimized partner solution, it will be up and running without any need for the customer to conduct testing of its own. Operational costs and complexity are also reduced, thanks to streamlined customer support through standardised configurations and pro-active monitoring. 'Engineered to Work Together' is a significant statement of Oracle strategy. It guarantees smoother deployment of a single vendor solution, clear ownership with no finger-pointing and the peace of mind of the Oracle Support Centre underpinning the entire product stack. Next steps Every OPN member with packaged applications must seriously consider taking steps to become Exastack Ready, or Exastack Optimized at the first opportunity. That first step down the track is to talk to an expert on the OPN Portal, at the Oracle Partner Business Center or to discuss the next steps with the closest Oracle account manager. Oracle Exastack lab environments and other technical enablement resources are available for OPN members wishing to further their knowledge of Oracle Exastack and qualify their applications for Oracle Exastack Optimized. New Boot Camps and Guided Learning Paths (GLPs), tailored specifically for ISVs, are available for Oracle Exadata Database Machine, Oracle Exalogic Elastic Cloud, Oracle Linux, Oracle Solaris, Oracle Database, and Oracle WebLogic Server. More information about these GLPs and Boot Camps (including delivery dates and locations) are posted on the OPN Competency Center and corresponding OPN Knowledge Zones. Learn more about Oracle Exastack labs and ISV specific enablement resources. "Oracle Specialized partners are of course front-and-centre, with potential customers clearly directed to those partners and to Exadata Ready partners as a matter of priority." --More OpenWorld 2011 highlights for Oracle partners and customers Oracle Application Testing Suite 9.3 application testing solution for Web, SOA and Oracle Applications Oracle Application Express Release 4.1 improving the development of database-centric Web 2.0 applications and reports Oracle Unified Directory 11g helping customers manage the critical identity information that drives their business applications Oracle SOA Suite for healthcare integration Oracle Enterprise Pack for Eclipse 11g demonstrating continued commitment to the developer and open source communities Oracle Coherence 3.7.1, the latest release of the industry's leading distributed in-memory data grid Oracle Process Accelerators helping to simplify and accelerate time-to-value for customers' business process management initiatives Oracle's JD Edwards EnterpriseOne on the iPad meeting the increasingly mobile demands of today's workforces Oracle CRM On Demand Release 19 Innovation Pack introducing industry-leading hosted call centre and enterprise-marketing capabilities designed to drive further revenue and productivity while reducing costs and improving the customer experience Oracle's Primavera Portfolio Management 9 for businesses delivering on project portfolio goals with increased versatility, transparency and accuracy Oracle's PeopleSoft Human Capital Management (HCM) 9.1 On Demand Standard Edition helping customers manage their long-term investment in enterprise-wide business applications New versions of Oracle FLEXCUBE Universal Banking and Oracle FLEXCUBE Investor Servicing for Financial Institutions, as well as Oracle Financial Services Enterprise Case Management, Oracle Financial Services Pricing Management, Oracle Financial Management Analytics and Oracle Tax Analytics Oracle Utilities Network Management System 1.11 offering new modelling and analysis features to improve distribution-grid management for electric utilities Oracle Communications Network Charging and Control 4.4 helping communications service providers (CSPs) offer their customers more flexible charging options Plus many, many more technology announcements, enhancements, momentum news and community updates -- Oracle OpenWorld 2012 A date has already been set for Oracle OpenWorld 2012. Held once again in San Francisco, exhibitors, partners, customers and Oracle people will gather from 30 September until 4 November to meet, network and learn together with the rest of the global Oracle community. Register now for Oracle OpenWorld 2012 and save $$$! We'll reward your early planning for Oracle OpenWorld 2012 with reduced rates. Super Saver deals are now available! -- Back to the welcome page

  Read the article

• I Hereby Resolve… (T-SQL Tuesday #14)

  - by smisner

  It’s time for another T-SQL Tuesday, hosted this month by Jen McCown (blog|twitter), on the topic of resolutions. Specifically, “what techie resolutions have you been pondering, and why?” I like that word – pondering – because I ponder a lot. And while there are many things that I do already because of my job, there are many more things that I ponder about doing…if only I had the time. Then I ponder about making time, but then it’s back to work! In 2010, I was moderately more successful in making time for things that I ponder about than I had been in years past, and I hope to continue that trend in 2011. If Jen hadn’t settled on this topic, I could keep my ponderings to myself and no one would ever know the outcome, but she’s egged me on (and everyone else that chooses to participate)! So here goes… For me, having resolve to do something means that I wouldn’t be doing that something as part of my ordinary routine. It takes extra effort to make time for it. It’s not something that I do once and check off a list, but something that I need to commit to over a period of time. So with that in mind, I hereby resolve… To Learn Something New… One of the things I love about my job is that I get to do a lot of things outside of my ordinary routine. It’s a veritable smorgasbord of opportunity! So what more could I possibly add to that list of things to do? Well, the more I learn, the more I realize I have so much more to learn. It would be much easier to remain in ignorant bliss, but I was born to learn. Constantly. (And apparently to teach, too– my father will tell you that as a small child, I had the neighborhood kids gathered together to play school – in the summer. I’m sure they loved that – but they did it!) These are some of things that I want to dedicate some time to learning this year: Spatial data. I have a good understanding of how maps in Reporting Services works, and I can cobble together a simple T-SQL spatial query, but I know I’m only scratching the surface here. Rob Farley (blog|twitter) posted interesting examples of combining maps and PivotViewer, and I think there’s so many more creative possibilities. I’ve always felt that pictures (including charts and maps) really help people get their minds wrapped around data better, and because a lot of data has a geographic aspect to it, I believe developing some expertise here will be beneficial to my work. PivotViewer. Not only is PivotViewer combined with maps a useful way to visualize data, but it’s an interesting way to work with data. If you haven’t seen it yet, check out this interactive demonstration using Netflx OData feed. According to Rob Farley, learning how to work with PivotViewer isn’t trivial. Just the type of challenge I like! Security. You’ve heard of the accidental DBA? Well, I am the accidental security person – is there a word for that role? My eyes used to glaze over when having to study about security, or  when reading anything about it. Then I had a problem long ago that no one could figure out – not even the vendor’s tech support – until I rolled up my sleeves and painstakingly worked through the myriad of potential problems to resolve a very thorny security issue. I learned a lot in the process, and have been able to share what I’ve learned with a lot of people. But I’m not convinced their eyes weren’t glazing over, too. I don’t take it personally – it’s just a very dry topic! So in addition to deepening my understanding about security, I want to find a way to make the subject as it relates to SQL Server and business intelligence more accessible and less boring. Well, there’s actually a lot more that I could put on this list, and a lot more things I have plans to do this coming year, but I run the risk of overcommitting myself. And then I wouldn’t have time… To Have Fun! My name is Stacia and I’m a workaholic. When I love what I do, it’s difficult to separate out the work time from the fun time. But there are some things that I’ve been meaning to do that aren’t related to business intelligence for which I really need to develop some resolve. And they are techie resolutions, too, in a roundabout sort of way! Photography. When my husband and I went on an extended camping trip in 2009 to Yellowstone and the Grand Tetons, I had a nice little digital camera that took decent pictures. But then I saw the gorgeous cameras that other tourists were toting around and decided I needed one too. So I bought a Nikon D90 and have started to learn to use it, but I’m definitely still in the beginning stages. I traveled so much in 2010 and worked on two book projects that I didn’t have a lot of free time to devote to it. I was very inspired by Kimberly Tripp’s (blog|twitter) and Paul Randal’s (blog|twitter) photo-adventure in Alaska, though, and plan to spend some dedicated time with my camera this year. (And hopefully before I move to Alaska – nothing set in stone yet, but we hope to move to a remote location – with Internet access – later this year!) Astronomy. I have this cool telescope, but it suffers the same fate as my camera. I have been gone too much and busy with other things that I haven’t had time to work with it. I’ll figure out how it works, and then so much time passes by that I forget how to use it. I have this crazy idea that I can actually put the camera and the telescope together for astrophotography, but I think I need to start simple by learning how to use each component individually. As long as I’m living in Las Vegas, I know I’ll have clear skies for nighttime viewing, but when we move to Alaska, we’ll be living in a rain forest. I have no idea what my opportunities will be like there – except I know that when the sky is clear, it will be far more amazing than anything I can see in Vegas – even out in the desert - because I’ll be so far away from city light pollution. I’ve been contemplating putting together a blog on these topics as I learn. As many of my fellow bloggers in the SQL Server community know, sometimes the best way to learn something is to sit down and write about it. I’m just stumped by coming up with a clever name for the new blog, which I was thinking about inaugurating with my move to Alaska. Except that I don’t know when that will be exactly, so we’ll just have to wait and see which comes first!

  Read the article

• TechEd 2010 Day One – How I Travel

  - by BuckWoody

  Normally when I blog on the first day of a conference, well, there hasn’t been a first day yet. So I talk about the value of a conference or some other facet. And normally in my (non-conference) blogs, I show you how I have learned to be a data professional – things I’ve learned how to do over the years. But in all that time, I don’t think I’ve ever talked about a big part of my job – traveling. I’ve traveled a lot throughout the years, when I’ve taught, gone to conferences, consulted and in my current role assisting Microsoft customers with large-scale database system designs.  So I’ll share a few thoughts about what I do. Keep in mind that I travel for short durations, just a day or so, and sometimes I travel internationally. For those I prepare differently – what I’m talking about here is what I do for a multi-day, same-country trip. Hopefully you find it useful. I’ll tag a few other travelers I know to add their thoughts.  Preparing for Travel   When I’m notified of a trip, I begin researching the location. I find the flights, hotel and (if I have to) a car to use while I’m away. We have an in-house system we use to book the travel, but when I travel not-for-Microsoft I use Expedia and Kayak to find what I need.  Traveling on Sunday and Friday is the worst. I have to do it sometimes (like this week) and it’s always a bad idea. But you can blunt the impact by booking as early as you can stand it. That means I have to be up super-early, but the flights are normally on time. I stay flexible, and always have a backup plan in case the flights are delayed or canceled.  For the hotel, I tend to go on the cheaper side, and I look for older hotels that have been renovated, or quirky ones. For instance, in Boise, ID recently I stayed at a 60’s-themed (think Mad-Men) hotel that was very cool. Always I go on the less expensive side – I find the “luxury” hotels nail me for Internet, food, everything. The cheaper places include all kinds of things, and even have breakfasts, shuttles and all kinds of things that start to add up. I even call ahead to make sure there’s an iron and ironing board available, since I’ll need those when I get there.  I find any way I can not to get a car. I use mass-transit wherever possible, and try to make friends and pay their gas to take me places. In a pinch, I’ll use a taxi. It ends up being cheaper, faster, and less stressful all around.  Packing  Over the years I’ve learned never to check luggage whenever I can. To do that, I lay out everything I want to take with me on the bed, and then try and make sure I’m really going to use it. I wear a dark wool set of pants, which I can clean and wear in hot and cold climates. I bring undies and socks of course, and for most places I have to wear “dress up” shirts. I bring at least two print T-Shirts in case I want to dress down for something while I’m gone, but I only bring one set of shoes. All the  clothes are rolled as tightly as possible as I learned in the military. Then I use those to cushion the electronics I take.  For toiletries I bring a shaver, toothpaste and toothbrush, D/O and a small brush. Everything else the hotel will provide.  For entertainment, I take a small Zune, a full PC-Headset (so I can make IP calls on the road) and my laptop. I don’t take books or anything else – everything is electronic. I use E-books (downloaded from our Library), Audio-Books (on the Zune) and I also bring along a Kaossilator (more here) to play music in the hotel room or even on the plane without being heard.  If I can, I pack into one roll-on bag. There’s not a lot better than this one, but I also have a Bag I was given as a prize for something or other here at Microsoft. Either way, I like something with less pockets and more big, open compartments. Everything gets rolled up and packed in, with all of the wires and charges in small bags my wife made for me. The laptop (and anything I don’t want gate-checked) goes on top or in an outside pouch so I can grab it quickly if I have to gate-check the bag. As much as I can, I try to go in one bag. When I can’t (like this week) I use this bag since it can expand, roll up, crush and even be put away later. It’s super-heavy canvas and worth the price. This allows me to not check a bag.  Journey Logistics The day of the trip, I have everything ready since I’m getting up early. I pack a few small snacks inside a plastic large-mouth water bottle, which protects the snacks and lets me get water in the terminal. I bring along those little powdered drink mixes to add to the water.  At the airport, I make a beeline for the power-outlets. I charge up my laptop and phone, and download all my e-mails so I can work on them off-line in the air. I don’t travel as often as I used to – just every month or so now, so I don’t have a membership to an airline club. If I travel much more, I’ll invest in one again – they are WELL worth the money, for the wifi, food and quiet if for nothing else.  I print out my logistics on paper and put that in my pocket – flight numbers, hotel addresses and phones for everything. That way if I have to make a change, I don’t have to boot up anything or even have power to be able to roll with the punches if things change.  Working While Away  While I’m away I realize I’m going to be swamped with things at the conference or with my clients. So I turn on Out-Of-Office notifications to let people know I won’t be as responsive, and I keep my Outlook calendar up to date so my co-workers know what I’m up to. I even update it with hotel and phone info in case they really need to reach me. I share my calendar with my wife so my family knows what I’m doing as well.  I check my e-mail during breaks, but I only respond to them in the evening or early morning at the hotel. I tweet during conferences. The point is to be as present as possible during the event or when I’m at the clients. Both deserve it.  So those are my initial thoughts. I’ll tag Brent Ozar, Brad McGeHee and Paul Randal, and they can tag whomever they wish. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

  Read the article

• Using SQL Execution Plans to discover the Swedish alphabet

  - by Rob Farley

  SQL Server is quite remarkable in a bunch of ways. In this post, I’m using the way that the Query Optimizer handles LIKE to keep it SARGable, the Execution Plans that result, Collations, and PowerShell to come up with the Swedish alphabet. SARGability is the ability to seek for items in an index according to a particular set of criteria. If you don’t have SARGability in play, you need to scan the whole index (or table if you don’t have an index). For example, I can find myself in the phonebook easily, because it’s sorted by LastName and I can find Farley in there by moving to the Fs, and so on. I can’t find everyone in my suburb easily, because the phonebook isn’t sorted that way. I can’t even find people who have six letters in their last name, because also the book is sorted by LastName, it’s not sorted by LEN(LastName). This is all stuff I’ve looked at before, including in the talk I gave at SQLBits in October 2010. If I try to find everyone who’s names start with F, I can do that using a query a bit like: SELECT LastName FROM dbo.PhoneBook WHERE LEFT(LastName,1) = 'F'; Unfortunately, the Query Optimizer doesn’t realise that all the entries that satisfy LEFT(LastName,1) = 'F' will be together, and it has to scan the whole table to find them. But if I write: SELECT LastName FROM dbo.PhoneBook WHERE LastName LIKE 'F%'; then SQL is smart enough to understand this, and performs an Index Seek instead. To see why, I look further into the plan, in particular, the properties of the Index Seek operator. The ToolTip shows me what I’m after: You’ll see that it does a Seek to find any entries that are at least F, but not yet G. There’s an extra Predicate in there (a Residual Predicate if you like), which checks that each LastName is really LIKE F% – I suppose it doesn’t consider that the Seek Predicate is quite enough – but most of the benefit is seen by its working out the Seek Predicate, filtering to just the “at least F but not yet G” section of the data. This got me curious though, particularly about where the G comes from, and whether I could leverage it to create the Swedish alphabet. I know that in the Swedish language, there are three extra letters that appear at the end of the alphabet. One of them is ä that appears in the word Västerås. It turns out that Västerås is quite hard to find in an index when you’re looking it up in a Swedish map. I talked about this briefly in my five-minute talk on Collation from SQLPASS (the one which was slightly less than serious). So by looking at the plan, I can work out what the next letter is in the alphabet of the collation used by the column. In other words, if my alphabet were Swedish, I’d be able to tell what the next letter after F is – just in case it’s not G. It turns out it is… Yes, the Swedish letter after F is G. But I worked this out by using a copy of my PhoneBook table that used the Finnish_Swedish_CI_AI collation. I couldn’t find how the Query Optimizer calculates the G, and my friend Paul White (@SQL_Kiwi) tells me that it’s frustratingly internal to the QO. He’s particularly smart, even if he is from New Zealand. To investigate further, I decided to do some PowerShell, leveraging the Get-SqlPlan function that I blogged about recently (make sure you also have the SqlServerCmdletSnapin100 snap-in added). I started by indicating that I was going to use Finnish_Swedish_CI_AI as my collation of choice, and that I’d start whichever letter cam straight after the number 9. I figure that this is a cheat’s way of guessing the first letter of the alphabet (but it doesn’t actually work in Unicode – luckily I’m using varchar not nvarchar. Actually, there are a few aspects of this code that only work using ASCII, so apologies if you were wanting to apply it to Greek, Japanese, etc). I also initialised my $alphabet variable. $collation = 'Finnish_Swedish_CI_AI'; $firstletter = '9'; $alphabet = ''; Now I created the table for my test. A single field would do, and putting a Clustered Index on it would suffice for the Seeks. Invoke-Sqlcmd -server . -data tempdb -query "create table dbo.collation_test (col varchar(10) collate $collation primary key);" Now I get into the looping. $c = $firstletter; $stillgoing = $true; while ($stillgoing) { I construct the query I want, seeking for entries which start with whatever $c has reached, and get the plan for it: $query = "select col from dbo.collation_test where col like '$($c)%';"; [xml] $pl = get-sqlplan $query "." "tempdb"; At this point, my $pl variable is a scary piece of XML, representing the execution plan. A bit of hunting through it showed me that the EndRange element contained what I was after, and that if it contained NULL, then I was done. $stillgoing = ($pl.ShowPlanXML.BatchSequence.Batch.Statements.StmtSimple.QueryPlan.RelOp.IndexScan.SeekPredicates.SeekPredicateNew.SeekKeys.EndRange -ne $null); Now I could grab the value out of it (which came with apostrophes that needed stripping), and append that to my $alphabet variable.   if ($stillgoing)   {  $c=$pl.ShowPlanXML.BatchSequence.Batch.Statements.StmtSimple.QueryPlan.RelOp.IndexScan.SeekPredicates.SeekPredicateNew.SeekKeys.EndRange.RangeExpressions.ScalarOperator.ScalarString.Replace("'","");     $alphabet += $c;   } Finally, finishing the loop, dropping the table, and showing my alphabet! } Invoke-Sqlcmd -server . -data tempdb -query "drop table dbo.collation_test;"; $alphabet; When I run all this, I see that the Swedish alphabet is ABCDEFGHIJKLMNOPQRSTUVXYZÅÄÖ, which matches what I see at Wikipedia. Interesting to see that the letters on the end are still there, even with Case Insensitivity. Turns out they’re not just “letters with accents”, they’re letters in their own right. I’m sure you gave up reading long ago, and really aren’t that fazed about the idea of doing this using PowerShell. I chose PowerShell because I’d already come up with an easy way of grabbing the estimated plan for a query, and PowerShell does allow for easy navigation of XML. I find the most interesting aspect of this as the fact that the Query Optimizer uses the next letter of the alphabet to maintain the SARGability of LIKE. I’m hoping they do something similar for a whole bunch of operations. Oh, and the fact that you know how to find stuff in the IKEA catalogue. Footnote: If you are interested in whether this works in other languages, you might want to consider the following screenshot, which shows that in principle, it should work with Japanese. It might be a bit harder to run this in PowerShell though, as I’m not sure how it translates. In Hiragana, the Japanese alphabet starts ?, ?, ?, ?, ?, ...

  Read the article

• The blocking nature of aggregates

  - by Rob Farley

  I wrote a post recently about how query tuning isn’t just about how quickly the query runs – that if you have something (such as SSIS) that is consuming your data (and probably introducing a bottleneck), then it might be more important to have a query which focuses on getting the first bit of data out. You can read that post here.  In particular, we looked at two operators that could be used to ensure that a query returns only Distinct rows. and The Sort operator pulls in all the data, sorts it (discarding duplicates), and then pushes out the remaining rows. The Hash Match operator performs a Hashing function on each row as it comes in, and then looks to see if it’s created a Hash it’s seen before. If not, it pushes the row out. The Sort method is quicker, but has to wait until it’s gathered all the data before it can do the sort, and therefore blocks the data flow. But that was my last post. This one’s a bit different. This post is going to look at how Aggregate functions work, which ties nicely into this month’s T-SQL Tuesday. I’ve frequently explained about the fact that DISTINCT and GROUP BY are essentially the same function, although DISTINCT is the poorer cousin because you have less control over it, and you can’t apply aggregate functions. Just like the operators used for Distinct, there are different flavours of Aggregate operators – coming in blocking and non-blocking varieties. The example I like to use to explain this is a pile of playing cards. If I’m handed a pile of cards and asked to count how many cards there are in each suit, it’s going to help if the cards are already ordered. Suppose I’m playing a game of Bridge, I can easily glance at my hand and count how many there are in each suit, because I keep the pile of cards in order. Moving from left to right, I could tell you I have four Hearts in my hand, even before I’ve got to the end. By telling you that I have four Hearts as soon as I know, I demonstrate the principle of a non-blocking operation. This is known as a Stream Aggregate operation. It requires input which is sorted by whichever columns the grouping is on, and it will release a row as soon as the group changes – when I encounter a Spade, I know I don’t have any more Hearts in my hand. Alternatively, if the pile of cards are not sorted, I won’t know how many Hearts I have until I’ve looked through all the cards. In fact, to count them, I basically need to put them into little piles, and when I’ve finished making all those piles, I can count how many there are in each. Because I don’t know any of the final numbers until I’ve seen all the cards, this is blocking. This performs the aggregate function using a Hash Match. Observant readers will remember this from my Distinct example. You might remember that my earlier Hash Match operation – used for Distinct Flow – wasn’t blocking. But this one is. They’re essentially doing a similar operation, applying a Hash function to some data and seeing if the set of values have been seen before, but before, it needs more information than the mere existence of a new set of values, it needs to consider how many of them there are. A lot is dependent here on whether the data coming out of the source is sorted or not, and this is largely determined by the indexes that are being used. If you look in the Properties of an Index Scan, you’ll be able to see whether the order of the data is required by the plan. A property called Ordered will demonstrate this. In this particular example, the second plan is significantly faster, but is dependent on having ordered data. In fact, if I force a Stream Aggregate on unordered data (which I’m doing by telling it to use a different index), a Sort operation is needed, which makes my plan a lot slower. This is all very straight-forward stuff, and information that most people are fully aware of. I’m sure you’ve all read my good friend Paul White (@sql_kiwi)’s post on how the Query Optimizer chooses which type of aggregate function to apply. But let’s take a look at SQL Server Integration Services. SSIS gives us a Aggregate transformation for use in Data Flow Tasks, but it’s described as Blocking. The definitive article on Performance Tuning SSIS uses Sort and Aggregate as examples of Blocking Transformations. I’ve just shown you that Aggregate operations used by the Query Optimizer are not always blocking, but that the SSIS Aggregate component is an example of a blocking transformation. But is it always the case? After all, there are plenty of SSIS Performance Tuning talks out there that describe the value of sorted data in Data Flow Tasks, describing the IsSorted property that can be set through the Advanced Editor of your Source component. And so I set about testing the Aggregate transformation in SSIS, to prove for sure whether providing Sorted data would let the Aggregate transform behave like a Stream Aggregate. (Of course, I knew the answer already, but it helps to be able to demonstrate these things). A query that will produce a million rows in order was in order. Let me rephrase. I used a query which produced the numbers from 1 to 1000000, in a single field, ordered. The IsSorted flag was set on the source output, with the only column as SortKey 1. Performing an Aggregate function over this (counting the number of rows per distinct number) should produce an additional column with 1 in it. If this were being done in T-SQL, the ordered data would allow a Stream Aggregate to be used. In fact, if the Query Optimizer saw that the field had a Unique Index on it, it would be able to skip the Aggregate function completely, and just insert the value 1. This is a shortcut I wouldn’t be expecting from SSIS, but certainly the Stream behaviour would be nice. Unfortunately, it’s not the case. As you can see from the screenshots above, the data is pouring into the Aggregate function, and not being released until all million rows have been seen. It’s not doing a Stream Aggregate at all. This is expected behaviour. (I put that in bold, because I want you to realise this.) An SSIS transformation is a piece of code that runs. It’s a physical operation. When you write T-SQL and ask for an aggregation to be done, it’s a logical operation. The physical operation is either a Stream Aggregate or a Hash Match. In SSIS, you’re telling the system that you want a generic Aggregation, that will have to work with whatever data is passed in. I’m not saying that it wouldn’t be possible to make a sometimes-blocking aggregation component in SSIS. A Custom Component could be created which could detect whether the SortKeys columns of the input matched the Grouping columns of the Aggregation, and either call the blocking code or the non-blocking code as appropriate. One day I’ll make one of those, and publish it on my blog. I’ve done it before with a Script Component, but as Script components are single-use, I was able to handle the data knowing everything about my data flow already. As per my previous post – there are a lot of aspects in which tuning SSIS and tuning execution plans use similar concepts. In both situations, it really helps to have a feel for what’s going on behind the scenes. Considering whether an operation is blocking or not is extremely relevant to performance, and that it’s not always obvious from the surface. In a future post, I’ll show the impact of blocking v non-blocking and synchronous v asynchronous components in SSIS, using some of LobsterPot’s Script Components and Custom Components as examples. When I get that sorted, I’ll make a Stream Aggregate component available for download.

  Read the article

• The blocking nature of aggregates

  - by Rob Farley

  I wrote a post recently about how query tuning isn’t just about how quickly the query runs – that if you have something (such as SSIS) that is consuming your data (and probably introducing a bottleneck), then it might be more important to have a query which focuses on getting the first bit of data out. You can read that post here.  In particular, we looked at two operators that could be used to ensure that a query returns only Distinct rows. and The Sort operator pulls in all the data, sorts it (discarding duplicates), and then pushes out the remaining rows. The Hash Match operator performs a Hashing function on each row as it comes in, and then looks to see if it’s created a Hash it’s seen before. If not, it pushes the row out. The Sort method is quicker, but has to wait until it’s gathered all the data before it can do the sort, and therefore blocks the data flow. But that was my last post. This one’s a bit different. This post is going to look at how Aggregate functions work, which ties nicely into this month’s T-SQL Tuesday. I’ve frequently explained about the fact that DISTINCT and GROUP BY are essentially the same function, although DISTINCT is the poorer cousin because you have less control over it, and you can’t apply aggregate functions. Just like the operators used for Distinct, there are different flavours of Aggregate operators – coming in blocking and non-blocking varieties. The example I like to use to explain this is a pile of playing cards. If I’m handed a pile of cards and asked to count how many cards there are in each suit, it’s going to help if the cards are already ordered. Suppose I’m playing a game of Bridge, I can easily glance at my hand and count how many there are in each suit, because I keep the pile of cards in order. Moving from left to right, I could tell you I have four Hearts in my hand, even before I’ve got to the end. By telling you that I have four Hearts as soon as I know, I demonstrate the principle of a non-blocking operation. This is known as a Stream Aggregate operation. It requires input which is sorted by whichever columns the grouping is on, and it will release a row as soon as the group changes – when I encounter a Spade, I know I don’t have any more Hearts in my hand. Alternatively, if the pile of cards are not sorted, I won’t know how many Hearts I have until I’ve looked through all the cards. In fact, to count them, I basically need to put them into little piles, and when I’ve finished making all those piles, I can count how many there are in each. Because I don’t know any of the final numbers until I’ve seen all the cards, this is blocking. This performs the aggregate function using a Hash Match. Observant readers will remember this from my Distinct example. You might remember that my earlier Hash Match operation – used for Distinct Flow – wasn’t blocking. But this one is. They’re essentially doing a similar operation, applying a Hash function to some data and seeing if the set of values have been seen before, but before, it needs more information than the mere existence of a new set of values, it needs to consider how many of them there are. A lot is dependent here on whether the data coming out of the source is sorted or not, and this is largely determined by the indexes that are being used. If you look in the Properties of an Index Scan, you’ll be able to see whether the order of the data is required by the plan. A property called Ordered will demonstrate this. In this particular example, the second plan is significantly faster, but is dependent on having ordered data. In fact, if I force a Stream Aggregate on unordered data (which I’m doing by telling it to use a different index), a Sort operation is needed, which makes my plan a lot slower. This is all very straight-forward stuff, and information that most people are fully aware of. I’m sure you’ve all read my good friend Paul White (@sql_kiwi)’s post on how the Query Optimizer chooses which type of aggregate function to apply. But let’s take a look at SQL Server Integration Services. SSIS gives us a Aggregate transformation for use in Data Flow Tasks, but it’s described as Blocking. The definitive article on Performance Tuning SSIS uses Sort and Aggregate as examples of Blocking Transformations. I’ve just shown you that Aggregate operations used by the Query Optimizer are not always blocking, but that the SSIS Aggregate component is an example of a blocking transformation. But is it always the case? After all, there are plenty of SSIS Performance Tuning talks out there that describe the value of sorted data in Data Flow Tasks, describing the IsSorted property that can be set through the Advanced Editor of your Source component. And so I set about testing the Aggregate transformation in SSIS, to prove for sure whether providing Sorted data would let the Aggregate transform behave like a Stream Aggregate. (Of course, I knew the answer already, but it helps to be able to demonstrate these things). A query that will produce a million rows in order was in order. Let me rephrase. I used a query which produced the numbers from 1 to 1000000, in a single field, ordered. The IsSorted flag was set on the source output, with the only column as SortKey 1. Performing an Aggregate function over this (counting the number of rows per distinct number) should produce an additional column with 1 in it. If this were being done in T-SQL, the ordered data would allow a Stream Aggregate to be used. In fact, if the Query Optimizer saw that the field had a Unique Index on it, it would be able to skip the Aggregate function completely, and just insert the value 1. This is a shortcut I wouldn’t be expecting from SSIS, but certainly the Stream behaviour would be nice. Unfortunately, it’s not the case. As you can see from the screenshots above, the data is pouring into the Aggregate function, and not being released until all million rows have been seen. It’s not doing a Stream Aggregate at all. This is expected behaviour. (I put that in bold, because I want you to realise this.) An SSIS transformation is a piece of code that runs. It’s a physical operation. When you write T-SQL and ask for an aggregation to be done, it’s a logical operation. The physical operation is either a Stream Aggregate or a Hash Match. In SSIS, you’re telling the system that you want a generic Aggregation, that will have to work with whatever data is passed in. I’m not saying that it wouldn’t be possible to make a sometimes-blocking aggregation component in SSIS. A Custom Component could be created which could detect whether the SortKeys columns of the input matched the Grouping columns of the Aggregation, and either call the blocking code or the non-blocking code as appropriate. One day I’ll make one of those, and publish it on my blog. I’ve done it before with a Script Component, but as Script components are single-use, I was able to handle the data knowing everything about my data flow already. As per my previous post – there are a lot of aspects in which tuning SSIS and tuning execution plans use similar concepts. In both situations, it really helps to have a feel for what’s going on behind the scenes. Considering whether an operation is blocking or not is extremely relevant to performance, and that it’s not always obvious from the surface. In a future post, I’ll show the impact of blocking v non-blocking and synchronous v asynchronous components in SSIS, using some of LobsterPot’s Script Components and Custom Components as examples. When I get that sorted, I’ll make a Stream Aggregate component available for download.

  Read the article

• Summit Time!

  - by Ajarn Mark Caldwell

  Boy, how time flies!  I can hardly believe that the 2011 PASS Summit is just one week away.  Maybe it snuck up on me because it’s a few weeks earlier than last year.  Whatever the cause, I am really looking forward to next week.  The PASS Summit is the largest SQL Server conference in the world and a fantastic networking opportunity thrown in for no additional charge.  Here are a few thoughts to help you maximize the week. Networking As Karen Lopez (blog | @DataChick) mentioned in her presentation for the Professional Development Virtual Chapter just a couple of weeks ago, “Don’t wait until you need a new job to start networking.”  You should always be working on your professional network.  Some people, especially technical-minded people, get confused by the term networking.  The first image that used to pop into my head was the image of some guy standing, awkwardly, off to the side of a cocktail party, trying to shmooze those around him.  That’s not what I’m talking about.  If you’re good at that sort of thing, and you can strike up a conversation with some stranger and learn all about them in 5 minutes, and walk away with your next business deal all but approved by the lawyers, then congratulations.  But if you’re not, and most of us are not, I have two suggestions for you.  First, register for Don Gabor’s 2-hour session on Tuesday at the Summit called Networking to Build Business Contacts.  Don is a master at small talk, and at teaching others, and in just those two short hours will help you with important tips about breaking the ice, remembering names, and smooth transitions into and out of conversations.  Then go put that great training to work right away at the Tuesday night Welcome Reception and meet some new people; which is really my second suggestion…just meet a few new people.  You see, “networking” is about meeting new people and being friendly without trying to “work it” to get something out of the relationship at this point.  In fact, Don will tell you that a better way to build the connection with someone is to look for some way that you can help them, not how they can help you. There are a ton of opportunities as long as you follow this one key point: Don’t stay in your hotel!  At the least, get out and go to the free events such as the Tuesday night Welcome Reception, the Wednesday night Exhibitor Reception, and the Thursday night Community Appreciation Party.  All three of these are perfect opportunities to meet other professionals with a similar job or interest as you, and you never know how that may help you out in the future.  Maybe you just meet someone to say HI to at breakfast the next day instead of eating alone.  Or maybe you cross paths several times throughout the Summit and compare notes on different sessions you attended.  And you just might make new friends that you look forward to seeing year after year at the Summit.  Who knows, it might even turn out that you have some specific experience that will help out that other person a few months’ from now when they run into the same challenge that you just overcame, or vice-versa.  But the point is, if you don’t get out and meet people, you’ll never have the chance for anything else to happen in the future. One more tip for shy attendees of the Summit…if you can’t bring yourself to strike up conversation with strangers at these events, then at the least, after you sit through a good session that helps you out, go up to the speaker and introduce yourself and thank them for taking the time and effort to put together their presentation.  Ideally, when you do this, tell them WHY it was beneficial to you (e.g. “Now I have a new idea of how to tackle a problem back at the office.”)  I know you think the speakers are all full of confidence and are always receiving a ton of accolades and applause, but you’re wrong.  Most of them will be very happy to hear first-hand that all the work they put into getting ready for their presentation is paying off for somebody. Training With over 170 technical sessions at the Summit, training is what it’s all about, and the training is fantastic!  Of course there are the big-name trainers like Paul Randall, Kimberly Tripp, Kalen Delaney, Itzik Ben-Gan and several others, but I am always impressed by the quality of the training put on by so many other “regular” members of the SQL Server community.  It is amazing how you don’t have to be a published author or otherwise recognized as an “expert” in an area in order to make a big impact on others just by sharing your personal experience and lessons learned.  I would rather hear the story of, and lessons learned from, “some guy or gal” who has actually been through an issue and came out the other side, than I would a trained professor who is speaking just from theory or an intellectual understanding of a topic. In addition to the three full days of regular sessions, there are also two days of pre-conference intensive training available.  There is an extra cost to this, but it is a fantastic opportunity.  Think about it…you’re already coming to this area for training, so why not extend your stay a little bit and get some in-depth training on a particular topic or two?  I did this for the first time last year.  I attended one day of extra training and it was well worth the time and money.  One of the best reasons for it is that I am extremely busy at home with my regular job and family, that it was hard to carve out the time to learn about the topic on my own.  It worked out so well last year that I am doubling up and doing two days or “pre-cons” this year. And then there are the DVDs.  I think these are another great option.  I used the online schedule builder to get ready and have an idea of which sessions I want to attend and when they are (much better than trying to figure this out at the last minute every day).  But the problem that I have run into (seems this happens every year) is that nearly every session block has two different sessions that I would like to attend.  And some of them have three!  ACK!  That won’t work!  What is a guy supposed to do?  Well, one option is to purchase the DVDs which are recordings of the audio and projected images from each session so you can continue to attend sessions long after the Summit is officially over.  Yes, many (possibly all) of these also get posted online and attendees can access those for no extra charge, but those are not necessarily all available as quickly as the DVD recording are, and the DVDs are often more convenient than downloading, especially if you want to share the training with someone who was not able to attend in person. Remember, I don’t make any money or get any other benefit if you buy the DVDs or from anything else that I have recommended here.  These are just my own thoughts, trying to help out based on my experiences from the 8 or so Summits I have attended.  There is nothing like the Summit.  It is an awesome experience, fantastic training, and a whole lot of fun which is just compounded if you’ll take advantage of the first part of this article and make some new friends along the way.

  Read the article

• Get Application Title from Windows Phone

  - by psheriff

  In a Windows Phone application that I am currently developing I needed to be able to retrieve the Application Title of the phone application. You can set the Deployment Title in the Properties of your Windows Phone Application, however getting to this value programmatically can be a little tricky. This article assumes that you have Visual Studio 2010 and the Windows Phone tools installed along with it. The Windows Phone tools must be downloaded separately and installed with Visual Studio2010. You may also download the free Visual Studio2010 Express for Windows Phone developer environment. The WMAppManifest.xml File First off you need to understand that when you set the Deployment Title in the Properties windows of your Windows Phone application, this title actually gets stored into an XML file located under the \Properties folder of your application. This XML file is named WMAppManifest.xml. A portion of this file is shown in the following listing. <?xml version="1.0" encoding="utf-8"?><Deployment  http://schemas.microsoft.com/windowsphone/2009/deployment"http://schemas.microsoft.com/windowsphone/2009/deployment"  AppPlatformVersion="7.0">  <App xmlns=""       ProductID="{71d20842-9acc-4f2f-b0e0-8ef79842ea53}"       Title="Mobile Time Track"       RuntimeType="Silverlight"       Version="1.0.0.0"       Genre="apps.normal"       Author="PDSA, Inc."       Description="Mobile Time Track"       Publisher="PDSA, Inc."> ... ...  </App></Deployment> Notice the “Title” attribute in the <App> element in the above XML document. This is the value that gets set when you modify the Deployment Title in your Properties Window of your Phone project. The only value you can set from the Properties Window is the Title. All of the other attributes you see here must be set by going into the XML file and modifying them directly. Note that this information duplicates some of the information that you can also set from the Assembly Information… button in the Properties Window. Why Microsoft did not just use that information, I don’t know. Reading Attributes from WMAppManifest I searched all over the namespaces and classes within the Windows Phone DLLs and could not find a way to read the attributes within the <App> element. Thus, I had to resort to good old fashioned XML processing. First off I created a WinPhoneCommon class and added two static methods as shown in the snippet below: public class WinPhoneCommon{  /// <summary>  /// Returns the Application Title   /// from the WMAppManifest.xml file  /// </summary>  /// <returns>The application title</returns>  public static string GetApplicationTitle()  {    return GetWinPhoneAttribute("Title");  }   /// <summary>  /// Returns the Application Description   /// from the WMAppManifest.xml file  /// </summary>  /// <returns>The application description</returns>  public static string GetApplicationDescription()  {    return GetWinPhoneAttribute("Description");  }   ... GetWinPhoneAttribute method here ...} In your Windows Phone application you can now simply call WinPhoneCommon.GetApplicationTitle() or WinPhone.GetApplicationDescription() to retrieve the Title or Description properties from the WMAppManifest.xml file respectively. You notice that each of these methods makes a call to the GetWinPhoneAttribute method. This method is shown in the following code snippet: /// <summary>/// Gets an attribute from the Windows Phone WMAppManifest.xml file/// To use this method, add a reference to the System.Xml.Linq DLL/// </summary>/// <param name="attributeName">The attribute to read</param>/// <returns>The Attribute's Value</returns>private static string GetWinPhoneAttribute(string attributeName){  string ret = string.Empty;   try  {    XElement xe = XElement.Load("WMAppManifest.xml");    var attr = (from manifest in xe.Descendants("App")                select manifest).SingleOrDefault();    if (attr != null)      ret = attr.Attribute(attributeName).Value;  }  catch  {    // Ignore errors in case this method is called    // from design time in VS.NET  }   return ret;} I love using the new LINQ to XML classes contained in the System.Xml.Linq.dll. When I did a Bing search the only samples I found for reading attribute information from WMAppManifest.xml used either an XmlReader or XmlReaderSettings objects. These are fine and work, but involve a little extra code. Instead of using these, I added a reference to the System.Xml.Linq.dll, then added two using statements to the top of the WinPhoneCommon class: using System.Linq;using System.Xml.Linq; Now, with just a few lines of LINQ to XML code you can read to the App element and extract the appropriate attribute that you pass into the GetWinPhoneAttribute method. Notice that I added a little bit of exception handling code in this method. I ignore the exception in case you call this method in the Loaded event of a user control. In design-time you cannot access the WMAppManifest file and thus an exception would be thrown. Summary In this article you learned how to retrieve the attributes from the WMAppManifest.xml file. I use this technique to grab information that I would otherwise have to hard-code in my application. Getting the Title or Description for your Windows Phone application is easy with just a little bit of LINQ to XML code. NOTE: You can download the complete sample code at my website. http://www.pdsa.com/downloads. Choose Tips & Tricks, then "Get Application Title from Windows Phone" from the drop-down. Good Luck with your Coding,Paul Sheriff ** SPECIAL OFFER FOR MY BLOG READERS **Visit http://www.pdsa.com/Event/Blog for a free video on Silverlight entitled Silverlight XAML for the Complete Novice - Part 1.  

  Read the article

• Agile Like Jazz

  - by Jeff Certain

  (I’ve been sitting on this for a week or so now, thinking that it needed to be tightened up a bit to make it less rambling. Since that’s clearly not going to happen, reader beware!) I had the privilege of spending around 90 minutes last night sitting and listening to Sonny Rollins play a concert at the Disney Center in LA. If you don’t know who Sonny Rollins is, I don’t know how to explain the experience; if you know who he is, I don’t need to. Suffice it to say that he has been recording professionally for over 50 years, and helped create an entire genre of music. A true master by any definition. One of the most intriguing aspects of a concert like this, however, is watching the master step aside and let the rest of the musicians play. Not just play their parts, but really play… letting them take over the spotlight, to strut their stuff, to soak up enthusiastic applause from the crowd. Maybe a lot of it has to do with the fact that Sonny Rollins has been doing this for more than a half-century. Maybe it has something to do with a kind of patience you learn when you’re on the far side of 80 – and the man can still blow a mean sax for 90 minutes without stopping! Maybe it has to do with the fact that he was out there for the love of the music and the love of the show, not because he had anything to prove to anyone and, I like to think, not for the money. Perhaps it had more to do with the fact that, when you’re at that level of mastery, the other musicians are going to be good. Really good. Whatever the reasons, there was a incredible freedom on that stage – the ability to improvise, for each musician to showcase their own specialization and skills, and them come back to the common theme, back to being on the same page, as it were. All this took place in the same venue that is home to the L.A. Phil. Somehow, I can’t ever see the same kind of free-wheeling improvisation happening in that context. And, since I’m a geek, I started thinking about agility. Rollins has put together a quintet that reflects his own particular style and past. No upright bass or piano for Rollins – drums, bongos, electric guitar and bass guitar along with his sax. It’s not about the mix of instruments. Other trios, quartets, and sextets use different mixes of instruments. New Orleans jazz tends towards trombones instead of sax; some prefer cornet or trumpet. But no matter what the choice of instruments, size matters. Team sizes are something I’ve been thinking about for a while. We’re on a quest to rethink how our teams are organized. They just feel too big, too unwieldy. In fact, they really don’t feel like teams at all. Most of the time, they feel more like collections or people who happen to report to the same manager. I attribute this to a couple factors. One is over-specialization; we have a tendency to have people work in silos. Although the teams are product-focused, within them our developers are both generalists and specialists. On the one hand, we expect them to be able to build an entire vertical slice of the application; on the other hand, each developer tends to be responsible for the vertical slice. As a result, developers often work on their own piece of the puzzle, in isolation. This sort of feels like working on a jigsaw in a group – each person taking a set of colors and piecing them together to reveal a portion of the overall picture. But what inevitably happens when you go to meld all those pieces together? Inevitably, you have some sections that are too big to move easily. These sections end up falling apart under their own weight as you try to move them. Not only that, but there are other challenges – figuring out where that section fits, and how to tie it into the rest of the puzzle. Often, this is when you find a few pieces need to be added – these pieces are “glue,” if you will. The other issue that arises is due to the overhead of maintaining communications in a team. My mother, who worked in IT for around 30 years, once told me that 20% per team member is a good rule of thumb for maintaining communication. While this is a rule of thumb, it seems to imply that any team over about 6 people is going to become less agile simple because of the communications burden. Teams of ten or twelve seem like they fall into the philharmonic organizational model. Complicated pieces of music requiring dozens of players to all be on the same page requires a much different model than the jazz quintet. There’s much less room for improvisation, originality or freedom. (There are probably orchestral musicians who will take exception to this characterization; I’m calling it like I see it from the cheap seats.) And, there’s one guy up front who is running the show, whose job is to keep all of those dozens of players on the same page, to facilitate communications. Somehow, the orchestral model doesn’t feel much like a self-organizing team, either. The first violin may be the best violinist in the orchestra, but they don’t get to perform free-wheeling solos. I’ve never heard of an orchestra getting together for a jam session. But I have heard of teams that organize their work based on the developers available, rather than organizing the developers based on the work required. I have heard of teams where desired functionality is deferred – or worse yet, schedules are missed – because one critical person doesn’t have any bandwidth available. I’ve heard of teams where people simply don’t have the big picture, because there is too much communication overhead for everyone to be aware of everything that is happening on a project. I once heard Paul Rayner say something to the effect of “you have a process that is perfectly designed to give you exactly the results you have.” Given a choice, I want a process that’s much more like jazz than orchestral music. I want a process that doesn’t burden me with lots of forms and checkboxes and stuff. Give me the simplest, most lightweight process that will work – and a smaller team of the best developers I can find. This seems like the kind of process that will get the kind of result I want to be part of.

  Read the article

• Emtel Knowledge Series - Q2/2014

  From Cyber Island to Smart Mauritius Cyber Island? Smart Mauritius? - What is Emtel talking about? "With the majority of the population living in urban environments today, the concept of "Smart Cities" has become an urgent necessity. "Smart Cities" refer to an urban transformation which, by using latest ICT technologies makes cities more efficient. Many Governments are setting out ambitious plans to build the cities of the future based on massive connectivity, high bandwidth communications, intelligent sensors and analysis of huge volumes of data. Various researches have shown four key enablers for smart city success - Government leadership, suitable technology infrastructure, solid public-private partnerships and engaged citizens. It is around these enabling factors that telecoms companies can play a vital role in assisting governments to deliver on the smart city vision." The Emtel Knowledge Series goes in compliance with Emtel's 25th anniversary celebrations throughout the year and the master of ceremony, Kim Andersen, mentioned that there will be more upcoming events on a quarterly base. As a representative of the Mauritius Software Craftsmanship Community (MSCC) there was absolutely no hesitation to join in again. Following my visit to the first Emtel Knowledge Series workshop back in February this year, it was great to have another opportunity to meet and exchange with technology experts. But quite frankly what is it with those buzz words... As far as I remember and how it was mentioned "Cyber Island" is an old initiative from around 2005/2006 which has been refreshed in 2010. It implies the empowerment of Information & Communication Technologies (ICT) as an essential factor of growth by the government here in Mauritius. Actually, the first promotional period of Cyber Island brought me here but that's another story. The venue and its own problems Like last time the event was organised and held at the Conference Hall at Cyber Tower I in Ebene. As I've been working there for some years, I know about the frustrating situation of finding a proper parking. So, does Smart Island include better solutions for the search of parking spaces? Maybe, let's see whether I will be able to answer that question at the end of the article. Anyway, after circling around the tower almost two times, I finally got a decent space to put the car, without risking to get a ticket or damage actually. International speakers and their experience Once again, Emtel did a great job to get international expertise onto the stage to share their experience and vision on this kind of embarkment. Personally, I really appreciated the fact they were speakers of global reach and could provide own-experience knowledge. Johan Gott spoke about the fundamental change that the Swedish government ignited in order to move their society and workers' environment away from heavy industry towards a knowledge-based approach. Additionally, we spoke about the effort and transformation of New York City into a greener and more efficient Smart City. Given modern technology he also advised that any kind of available Big Data should be opened to the general public - this openness would provide a playground for anyone to garner new ideas and most probably solid solutions of which no one else thought about before. Emtel Knowledge Series on moving from Cyber Island to Smart Mauritus Later during the afternoon that exact statement regarding openness to and transparency of government-owned Big Data has been emphasised again by the Danish speaker Kim Andersen and his former colleague Mika Jantunen from Finland. Mika continued to underline the important role of the government to provide a solid foundation for a knowledge-based society and mentioned that Finnish citizens have a constitutional right to broadband connectivity. Next to free higher (tertiary) education Finland already produced a good number of innovations, among them are: First country to grant voting rights to women Free higher education Constitutional right to broadband connectivity Nokia Linux Angry Birds Sauna and others...  General access to internet via broadband and/or mobile connectivity is surely a key factor towards Smart Cities, or better said Smart Mauritius given the area dimensions and size of population. CTO Paul Valette gave the audience a brief overview of the essential role that Emtel will have to move Mauritius forward towards a knowledge-based and innovation-driven environment for its citizen. What I have seen looks really promising and with recently published information that Mauritians have 127% of mobile capacity - meaning more than 1 mobile, smartphone or tablet per person - it will be crucial to have the right infrastructure for these connected devices. How would it be possible to achieve a knowledge-based society? YouTube to the rescue!Seriously, gaining more knowledge will require to have fast access to educational course material as explained by Dr Kaviraj Sukon, General Director of the Open University of Mauritius. According to him a good number of high-profile universities in the world have opened their course libraries to the general public, among them EDX, Coursera and Open University. Nowadays, you're actually able and enabled to learn for and earn a BSc or even MSc certification on your own pace - no need to attend classed on campus. It was really impressive to see the number of available hours - more than enough for a life-long learning experience! {loadposition content_adsense} Networking in the name of MSCC As briefly mentioned above I was about to combine two approaches for this workshop. Of course, getting latest information and updates on Emtel services available, especially for my business here on the west coast of the island, but also to meet and greet new people for the MSCC. And I think it was very positive on both sides. Let me quickly describe some of the key aspects that happened during the day: Met with Arnaud Meslier and Kellie, both Microsoft to swap latest information on IT events. Hereby, I got an invite to Microsoft Windows Phone 8.1 Dev Camp. Got in touch with Arvin Lockee, Emtel to check our options to meet with the data team, and seizing the opportunity to have a visiting tour at the Emtel Data Centre. Had a great chat with Avinash Meetoo, Knowledge 7, Kim Andersen and Mika Jantunen about the situation of teaching and learning in general and specifically in the private sector here in Mauritius. Additionally, a number of various other interesting chats... Once again, I'm catching up on a couple of business cards in order to provide more background information about the MSCC, and to create a better awareness of MSCC within the local IT businesses. There is more to come soon!  Resume of the day The number of attendees during this event has been doubled or even tripled this time. The whole organisation has been improved massively and the combination of presentation and summarizing panel discussions was better than during the previous workshop back in February. Overall, once again a well-organised workshop and I'm already looking forward to join the next workshop in Q3. Update End of July we finally managed to visit the Emtel Data Centre in Arsenal. It was an interesting opportunity for some of our MSCC members.

  Read the article

• Using a WPF ListView as a DataGrid

  - by psheriff

  Many people like to view data in a grid format of rows and columns. WPF did not come with a data grid control that automatically creates rows and columns for you based on the object you pass it. However, the WPF Toolkit can be downloaded from CodePlex.com that does contain a DataGrid control. This DataGrid gives you the ability to pass it a DataTable or a Collection class and it will automatically figure out the columns or properties and create all the columns for you and display the data.The DataGrid control also supports editing and many other features that you might not always need. This means that the DataGrid does take a little more time to render the data. If you want to just display data (see Figure 1) in a grid format, then a ListView works quite well for this task. Of course, you will need to create the columns for the ListView, but with just a little generic code, you can create the columns on the fly just like the WPF Toolkit’s DataGrid. Figure 1: A List of Data using a ListView A Simple ListView ControlThe XAML below is what you would use to create the ListView shown in Figure 1. However, the problem with using XAML is you have to pre-define the columns. You cannot re-use this ListView except for “Product” data. <ListView x:Name="lstData"          ItemsSource="{Binding}">  <ListView.View>    <GridView>      <GridViewColumn Header="Product ID"                      Width="Auto"               DisplayMemberBinding="{Binding Path=ProductId}" />      <GridViewColumn Header="Product Name"                      Width="Auto"               DisplayMemberBinding="{Binding Path=ProductName}" />      <GridViewColumn Header="Price"                      Width="Auto"               DisplayMemberBinding="{Binding Path=Price}" />    </GridView>  </ListView.View></ListView> So, instead of creating the GridViewColumn’s in XAML, let’s learn to create them in code to create any amount of columns in a ListView. Create GridViewColumn’s From Data TableTo display multiple columns in a ListView control you need to set its View property to a GridView collection object. You add GridViewColumn objects to the GridView collection and assign the GridView to the View property. Each GridViewColumn object needs to be bound to a column or property name of the object that the ListView will be bound to. An ADO.NET DataTable object contains a collection of columns, and these columns have a ColumnName property which you use to bind to the GridViewColumn objects. Listing 1 shows a sample of reading and XML file into a DataSet object. After reading the data a GridView object is created. You can then loop through the DataTable columns collection and create a GridViewColumn object for each column in the DataTable. Notice the DisplayMemberBinding property is set to a new Binding to the ColumnName in the DataTable. C#private void FirstSample(){  // Read the data  DataSet ds = new DataSet();  ds.ReadXml(GetCurrentDirectory() + @"\Xml\Product.xml");    // Create the GridView  GridView gv = new GridView();   // Create the GridView Columns  foreach (DataColumn item in ds.Tables[0].Columns)  {    GridViewColumn gvc = new GridViewColumn();    gvc.DisplayMemberBinding = new Binding(item.ColumnName);    gvc.Header = item.ColumnName;    gvc.Width = Double.NaN;    gv.Columns.Add(gvc);  }   // Setup the GridView Columns  lstData.View = gv;  // Display the Data  lstData.DataContext = ds.Tables[0];} VB.NETPrivate Sub FirstSample()  ' Read the data  Dim ds As New DataSet()  ds.ReadXml(GetCurrentDirectory() & "\Xml\Product.xml")   ' Create the GridView  Dim gv As New GridView()   ' Create the GridView Columns  For Each item As DataColumn In ds.Tables(0).Columns    Dim gvc As New GridViewColumn()    gvc.DisplayMemberBinding = New Binding(item.ColumnName)    gvc.Header = item.ColumnName    gvc.Width = [Double].NaN    gv.Columns.Add(gvc)  Next   ' Setup the GridView Columns  lstData.View = gv  ' Display the Data  lstData.DataContext = ds.Tables(0)End SubListing 1: Loop through the DataTable columns collection to create GridViewColumn objects A Generic Method for Creating a GridViewInstead of having to write the code shown in Listing 1 for each ListView you wish to create, you can create a generic method that given any DataTable will return a GridView column collection. Listing 2 shows how you can simplify the code in Listing 1 by setting up a class called WPFListViewCommon and create a method called CreateGridViewColumns that returns your GridView. C#private void DataTableSample(){  // Read the data  DataSet ds = new DataSet();  ds.ReadXml(GetCurrentDirectory() + @"\Xml\Product.xml");   // Setup the GridView Columns  lstData.View =      WPFListViewCommon.CreateGridViewColumns(ds.Tables[0]);  lstData.DataContext = ds.Tables[0];} VB.NETPrivate Sub DataTableSample()  ' Read the data  Dim ds As New DataSet()  ds.ReadXml(GetCurrentDirectory() & "\Xml\Product.xml")   ' Setup the GridView Columns  lstData.View = _      WPFListViewCommon.CreateGridViewColumns(ds.Tables(0))  lstData.DataContext = ds.Tables(0)End SubListing 2: Call a generic method to create GridViewColumns. The CreateGridViewColumns MethodThe CreateGridViewColumns method will take a DataTable as a parameter and create a GridView object with a GridViewColumn object in its collection for each column in your DataTable. C#public static GridView CreateGridViewColumns(DataTable dt){  // Create the GridView  GridView gv = new GridView();  gv.AllowsColumnReorder = true;   // Create the GridView Columns  foreach (DataColumn item in dt.Columns)  {    GridViewColumn gvc = new GridViewColumn();    gvc.DisplayMemberBinding = new Binding(item.ColumnName);    gvc.Header = item.ColumnName;    gvc.Width = Double.NaN;    gv.Columns.Add(gvc);  }   return gv;} VB.NETPublic Shared Function CreateGridViewColumns _  (ByVal dt As DataTable) As GridView  ' Create the GridView  Dim gv As New GridView()  gv.AllowsColumnReorder = True   ' Create the GridView Columns  For Each item As DataColumn In dt.Columns    Dim gvc As New GridViewColumn()    gvc.DisplayMemberBinding = New Binding(item.ColumnName)    gvc.Header = item.ColumnName    gvc.Width = [Double].NaN    gv.Columns.Add(gvc)  Next   Return gvEnd FunctionListing 3: The CreateGridViewColumns method takes a DataTable and creates GridViewColumn objects in a GridView. By separating this method out into a class you can call this method anytime you want to create a ListView with a collection of columns from a DataTable. SummaryIn this blog you learned how to create a ListView that acts like a DataGrid. You are able to use a DataTable as both the source of the data, and for creating the columns for the ListView. In the next blog entry you will learn how to use the same technique, but for Collection classes. NOTE: You can download the complete sample code (in both VB and C#) at my website. http://www.pdsa.com/downloads. Choose Tips & Tricks, then "WPF ListView as a DataGrid" from the drop-down. Good Luck with your Coding,Paul Sheriff ** SPECIAL OFFER FOR MY BLOG READERS **Visit http://www.pdsa.com/Event/Blog for a free eBook on "Fundamentals of N-Tier".

  Read the article

• WPF ListView as a DataGrid – Part 2

  - by psheriff

  In my last blog post I showed you how to create GridViewColumn objects on the fly from the meta-data in a DataTable. By doing this you can create columns for a ListView at runtime instead of having to pre-define each ListView for each different DataTable. Well, many of us use collections of our classes and it would be nice to be able to do the same thing for our collection classes as well. This blog post will show you one approach for using collection classes as the source of the data for your ListView.  Figure 1: A List of Data using a ListView Load Property NamesYou could use reflection to gather the property names in your class, however there are two things wrong with this approach. First, reflection is too slow, and second you may not want to display all your properties from your class in the ListView. Instead of reflection you could just create your own custom collection class of PropertyHeader objects. Each PropertyHeader object will contain a property name and a header text value at a minimum. You could add a width property if you wanted as well. All you need to do is to create a collection of property header objects where each object represents one column in your ListView. Below is a simple example: PropertyHeaders coll = new PropertyHeaders(); coll.Add(new PropertyHeader("ProductId", "Product ID"));coll.Add(new PropertyHeader("ProductName", "Product Name"));coll.Add(new PropertyHeader("Price", "Price")); Once you have this collection created, you could pass this collection to a method that would create the GridViewColumn objects based on the information in this collection. Below is the full code for the PropertyHeader class. Besides the PropertyName and Header properties, there is a constructor that will allow you to set both properties when the object is created. C#public class PropertyHeader{  public PropertyHeader()  {  }   public PropertyHeader(string propertyName, string headerText)  {    PropertyName = propertyName;    HeaderText = headerText;  }   public string PropertyName { get; set; }  public string HeaderText { get; set; }} VB.NETPublic Class PropertyHeader  Public Sub New()  End Sub   Public Sub New(ByVal propName As String, ByVal header As String)    PropertyName = propName    HeaderText = header  End Sub   Private mPropertyName As String  Private mHeaderText As String   Public Property PropertyName() As String    Get      Return mPropertyName    End Get    Set(ByVal value As String)      mPropertyName = value    End Set  End Property   Public Property HeaderText() As String    Get      Return mHeaderText    End Get    Set(ByVal value As String)      mHeaderText = value    End Set  End PropertyEnd Class You can use a Generic List class to create a collection of PropertyHeader objects as shown in the following code. C#public class PropertyHeaders : List<PropertyHeader>{} VB.NETPublic Class PropertyHeaders  Inherits List(Of PropertyHeader)End Class Create Property Header Objects You need to create a method somewhere that will create and return a collection of PropertyHeader objects that will represent the columns you wish to add to your ListView prior to binding your collection class to that ListView. Below is a sample method called GetProperties that builds a list of PropertyHeader objects with properties and headers for a Product object. C#public PropertyHeaders GetProperties(){  PropertyHeaders coll = new PropertyHeaders();   coll.Add(new PropertyHeader("ProductId", "Product ID"));  coll.Add(new PropertyHeader("ProductName", "Product Name"));  coll.Add(new PropertyHeader("Price", "Price"));   return coll;} VB.NETPublic Function GetProperties() As PropertyHeaders  Dim coll As New PropertyHeaders()   coll.Add(New PropertyHeader("ProductId", "Product ID"))  coll.Add(New PropertyHeader("ProductName", "Product Name"))  coll.Add(New PropertyHeader("Price", "Price"))   Return collEnd Function WPFListViewCommon Class Now that you have a collection of PropertyHeader objects you need a method that will create a GridView and a collection of GridViewColumn objects based on this PropertyHeader collection. Below is a static/Shared method that you might put into a class called WPFListViewCommon. C#public static GridView CreateGridViewColumns(  PropertyHeaders properties){  GridView gv;  GridViewColumn gvc;   // Create the GridView  gv = new GridView();  gv.AllowsColumnReorder = true;   // Create the GridView Columns  foreach (PropertyHeader item in properties)  {    gvc = new GridViewColumn();    gvc.DisplayMemberBinding = new Binding(item.PropertyName);    gvc.Header = item.HeaderText;    gvc.Width = Double.NaN;    gv.Columns.Add(gvc);  }   return gv;} VB.NETPublic Shared Function CreateGridViewColumns( _    ByVal properties As PropertyHeaders) As GridView  Dim gv As GridView  Dim gvc As GridViewColumn   ' Create the GridView  gv = New GridView()  gv.AllowsColumnReorder = True   ' Create the GridView Columns  For Each item As PropertyHeader In properties    gvc = New GridViewColumn()    gvc.DisplayMemberBinding = New Binding(item.PropertyName)    gvc.Header = item.HeaderText    gvc.Width = [Double].NaN    gv.Columns.Add(gvc)  Next   Return gvEnd Function Build the Product Screen To build the window shown in Figure 1, you might write code like the following: C#private void CollectionSample(){  Product prod = new Product();   // Setup the GridView Columns  lstData.View = WPFListViewCommon.CreateGridViewColumns(       prod.GetProperties());  lstData.DataContext = prod.GetProducts();} VB.NETPrivate Sub CollectionSample()  Dim prod As New Product()   ' Setup the GridView Columns  lstData.View = WPFListViewCommon.CreateGridViewColumns( _       prod.GetProperties())  lstData.DataContext = prod.GetProducts()End Sub The Product class contains a method called GetProperties that returns a PropertyHeaders collection. You pass this collection to the WPFListViewCommon’s CreateGridViewColumns method and it will create a GridView for the ListView. When you then feed the DataContext property of the ListView the Product collection the appropriate columns have already been created and data bound. Summary In this blog you learned how to create a ListView that acts like a DataGrid using a collection class. While it does take a little code to do this, it is an alternative to creating each GridViewColumn in XAML. This gives you a lot of flexibility. You could even read in the property names and header text from an XML file for a truly configurable ListView. NOTE: You can download the complete sample code (in both VB and C#) at my website. http://www.pdsa.com/downloads. Choose Tips & Tricks, then "WPF ListView as a DataGrid – Part 2" from the drop-down. Good Luck with your Coding,Paul Sheriff ** SPECIAL OFFER FOR MY BLOG READERS **Visit http://www.pdsa.com/Event/Blog for a free eBook on "Fundamentals of N-Tier".  

  Read the article

< Previous Page | 71 72 73 74 75 76  | Next Page >