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• Silverlight Cream for June 10, 2010 -- #879

  - by Dave Campbell

  In this Issue: Emiel Jongerius, Nokola, Christian Schormann, Tim Heuer, David Poll, Mike Snow(-2-), John Papa, and Charles Petzold. Shoutout: Viktor Larsson has a frank look at WP7 based on information from MIX10 and what was said this week in his post: Licking Windows Phone 7... yeah licking, not liking :) .. my guess is even that didn't allow him to keep it! If you haven't already noticed, the CodeProject reader's choice awards are out this week and Telerik won for their RadColorPicker and RadCalendar for Silverlight Telerik also needs congratulations for winning Telerik wins “Best of TechEd” award in the “Components and Middleware” category... check out that trophy... Steven Forte has a picture up of the Telerikers after getting the award. Koen Zwikstra has a new release of Silverlight Spy up that supports the latest release: Silverlight Spy 3.0.0.12 From SilverlightCream.com: Localization of XAML files in Silverlight Emiel Jongerius is back with another post, this time discussing Localizing XAM files... external links and source included. Coolest Silverlight Sound Library for Games I've Seen Yet Nokola talks up a Sound Library for Silverlight 4 Games ... and has links to a great demo, plus the source. SketchFlow: Firing Actions when a Storyboard is Complete Christian Schormann responded to some Twitter questions and demonstrates using the StoryboardCompleted trigger with a Navigate action. Hosting cross-domain Silverlight applications (XAP) Tim Heuer responds to a question from a reader and demonstrates how to host a XAP from a domain other than the one you're working on. Taking Microsoft Silverlight 4 Applications Beyond the Browser (TechEd WEB313) David Poll has all his material up from his TechEd presentation earlier this week on Silverlight OOB... and he covered some pretty extensive material ... check it out! Silverlight Tip of the Day #29 – Configuring Service Reference to Back to LocalHost Mike Snow has a couple new tips up... this first one is quick, but very useful... how to switch your service reference back to localhost without pulling out your hair. Silverlight Tip of the Day #30 – Sending Email from Silverlight In Mike Snow's latest tip, he shows how to send email from your Silverlight app... using a WCF service... and a step-by-step set of instructions. Creating Rich Interactions Using Blend 4: Transition Effects, Fluid Layout and Layout States (Silverlight TV #32) John Papa has Silverlight TV #32 up, and he's talking with Kenny Young of the Expression Blend team while Kenny uses some built-om effects and also creates some impressive examples from scratch -- code included. Simulating Touch Inertia on Windows Phone 7 Charles Petzold has a post up on simulating inertia on WP7... demos in WPF and then moves into WP7... math, source, and external links. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

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• How to wire finite state machine into component-based architecture?

  - by Pup

  State machines seem to cause harmful dependencies in component-based architectures. How, specifically, is communication handled between a state machine and the components that carry out state-related behavior? Where I'm at: I'm new to component-based architectures. I'm making a fighting game, although I don't think that should matter. I envision my state machine being used to toggle states like "crouching", "dashing", "blocking", etc. I've found this state-management technique to be the most natural system for a component-based architecture, but it conflicts with techniques I've read about: Dynamic Game Object Component System for Mutable Behavior Characters It suggests that all components activate/deactivate themselves by continually checking a condition for activation. I think that actions like "running" or "walking" make sense as states, which is in disagreement with the accepted response here: finite state machine used in mario like platform game I've found this useful, but ambiguous: How to implement behavior in a component-based game architecture? It suggests having a separate component that contains nothing but a state machine. But, this necessitates some kind of coupling between the state machine component and nearly all the other components. I don't understand how this coupling should be handled. These are some guesses: A. Components depend on state machine: Components receive reference to state machine component's getState(), which returns an enumeration constant. Components update themselves regularly and check this as needed. B. State machine depends on components: The state machine component receives references to all the components it's monitoring. It queries their getState() methods to see where they're at. C. Some abstraction between them Use an event hub? Command pattern? D. Separate state objects that reference components State Pattern is used. Separate state objects are created, which activate/deactivate a set of components. State machine switches between state objects. I'm looking at components as implementations of aspects. They do everything that's needed internally to make that aspect happen. It seems like components should function on their own, without relying on other components. I know some dependencies are necessary, but state machines seem to want to control all of my components.

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• International Radio Operators Alphabet in F# &amp; Silverlight &ndash; Part 2

  - by MarkPearl

  So the brunt of my my very complex F# code has been done. Now it’s just putting the Silverlight stuff in. The first thing I did was add a new project to my solution. I gave it a name and VS2010 did the rest of the magic in creating the .Web project etc. In this instance because I want to take the MVVM approach and make use of commanding I have decided to make the frontend a Silverlight4 project. I now need move my F# code into a proper Silverlight Library. Warning – when you create the Silverlight Library VS2010 will ask you whether you want it to be based on Silverlight3 or Silverlight4. I originally went for Silverlight4 only to discover when I tried to compile my solution that I was given an error… Error 12 F# runtime for Silverlight version v4.0 is not installed. Please go to http://go.microsoft.com/fwlink/?LinkId=177463 to download and install matching.. After asking around I discovered that the Silverlight4 F# runtime is not available yet. No problem, the suggestion was to change the F# Silverlight Library to a Silverlight3 project however when going to the properties of the project file – even though I changed it to Silverlight3, VS2010 did not like it and kept reverting it to a Silverlight4 project. After a few minutes of scratching my head I simply deleted Silverlight4 F# Library project and created a new F# Silverlight Library project in Silverlight3 and VS2010 was happy. Now that the project structure is set up, rest is fairly simple. You need to add the Silverlight Library as a reference to the C# Silverlight Front End. Then setup your views, since I was following the MVVM pattern I made a Views & ViewModel folder and set up the relevant View and ViewModels. The MainPageViewModel file looks as follows using System; using System.Net; using System.Windows; using System.Windows.Controls; using System.Windows.Documents; using System.Windows.Ink; using System.Windows.Input; using System.Windows.Media; using System.Windows.Media.Animation; using System.Windows.Shapes; using System.Collections.ObjectModel; namespace IROAFrontEnd.ViewModels { public class MainPageViewModel : ViewModelBase { private string _iroaString; private string _inputCharacters; public string InputCharacters { get { return _inputCharacters; } set { if (_inputCharacters != value) { _inputCharacters = value; OnPropertyChanged("InputCharacters"); } } } public string IROAString { get { return _iroaString; } set { if (_iroaString != value) { _iroaString = value; OnPropertyChanged("IROAString"); } } } public ICommand MySpecialCommand { get { return new MyCommand(this); } } public class MyCommand : ICommand { readonly MainPageViewModel _myViewModel; public MyCommand(MainPageViewModel myViewModel) { _myViewModel = myViewModel; } public event EventHandler CanExecuteChanged; public bool CanExecute(object parameter) { return true; } public void Execute(object parameter) { var result = ModuleMain.ConvertCharsToStrings(_myViewModel.InputCharacters); var newString = ""; foreach (var Item in result) { newString += Item + " "; } _myViewModel.IROAString = newString.Trim(); } } } } One of the features I like in Silverlight4 is the new commanding. You will notice in my I have put the code under the command execute to reference to my F# module. At the moment this could be cleaned up even more, but will suffice for now.. public void Execute(object parameter) { var result = ModuleMain.ConvertCharsToStrings(_myViewModel.InputCharacters); var newString = ""; foreach (var Item in result) { newString += Item + " "; } _myViewModel.IROAString = newString.Trim(); } I then needed to set the view up. If we have a look at the MainPageView.xaml the xaml code will look like the following…. Nothing to fancy, but battleship grey for now… take careful note of the binding of the command in the button to MySpecialCommand which was created in the ViewModel. <UserControl x:Class="IROAFrontEnd.Views.MainPageView" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="400"> <Grid x:Name="LayoutRoot" Background="White"> <Grid.RowDefinitions> <RowDefinition/> <RowDefinition/> <RowDefinition/> </Grid.RowDefinitions> <TextBox Grid.Row="0" Text="{Binding InputCharacters, Mode=TwoWay}"/> <Button Grid.Row="1" Command="{Binding MySpecialCommand}"> <TextBlock Text="Generate"/> </Button> <TextBlock Grid.Row="2" Text="{Binding IROAString}"/> </Grid> </UserControl> Finally in the App.xaml.cs file we need to set the View and link it to the ViewModel. private void Application_Startup(object sender, StartupEventArgs e) { var myView = new MainPageView(); var myViewModel = new MainPageViewModel(); myView.DataContext = myViewModel; this.RootVisual = myView; }   Once this is done – hey presto – it worked. I typed in some “Test Input” and clicked the generate button and the correct Radio Operators Alphabet was generated. And that’s the end of my first very basic F# Silverlight application.

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• Shadow-mapping xna

  - by Kurt Ricci

  I've been trying to implement shadows in my game and I've been following quite a few tutorials online, mainly Riemers, but I'm always getting the same 2 errors when I'm drawing my models and setting the parameters from the effect file. The errors are: This method does not accept null for this parameter. Parameter name: value and Object reference not set to an instance of an object. So I've then downloaded a sample and just replaced my model with the one found in the sample and the same errors occur. I this find very strange as it works with his model. I'm wondering if the problem is with my models (I made them myself). Here's the code where the errors occur (they start to occur after the second foreach loop). Any help would be greatly appreciated, thanks.

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• C#: Why Decorate When You Can Intercept

  - by James Michael Hare

  We've all heard of the old Decorator Design Pattern (here) or used it at one time or another either directly or indirectly.  A decorator is a class that wraps a given abstract class or interface and presents the same (or a superset) public interface but "decorated" with additional functionality.   As a really simplistic example, consider the System.IO.BufferedStream, it itself is a descendent of System.IO.Stream and wraps the given stream with buffering logic while still presenting System.IO.Stream's public interface:   1: Stream buffStream = new BufferedStream(rawStream); Now, let's take a look at a custom-code example.  Let's say that we have a class in our data access layer that retrieves a list of products from a database:  1: // a class that handles our CRUD operations for products 2: public class ProductDao 3: { 4: ... 5:  6: // a method that would retrieve all available products 7: public IEnumerable<Product> GetAvailableProducts() 8: { 9: var results = new List<Product>(); 10:  11: // must create the connection 12: using (var con = _factory.CreateConnection()) 13: { 14: con.ConnectionString = _productsConnectionString; 15: con.Open(); 16:  17: // create the command 18: using (var cmd = _factory.CreateCommand()) 19: { 20: cmd.Connection = con; 21: cmd.CommandText = _getAllProductsStoredProc; 22: cmd.CommandType = CommandType.StoredProcedure; 23:  24: // get a reader and pass back all results 25: using (var reader = cmd.ExecuteReader()) 26: { 27: while(reader.Read()) 28: { 29: results.Add(new Product 30: { 31: Name = reader["product_name"].ToString(), 32: ... 33: }); 34: } 35: } 36: } 37: }            38:  39: return results; 40: } 41: } Yes, you could use EF or any myriad other choices for this sort of thing, but the germaine point is that you have some operation that takes a non-trivial amount of time.  What if, during the production day I notice that my application is performing slowly and I want to see how much of that slowness is in the query versus my code.  Well, I could easily wrap the logic block in a System.Diagnostics.Stopwatch and log the results to log4net or other logging flavor of choice: 1:     // a class that handles our CRUD operations for products 2:     public class ProductDao 3:     { 4:         private static readonly ILog _log = LogManager.GetLogger(typeof(ProductDao)); 5:         ... 6:         7:         // a method that would retrieve all available products 8:         public IEnumerable<Product> GetAvailableProducts() 9:         { 10:             var results = new List<Product>(); 11:             var timer = Stopwatch.StartNew(); 12:             13:             // must create the connection 14:             using (var con = _factory.CreateConnection()) 15:             { 16:                 con.ConnectionString = _productsConnectionString; 17:                 18:                 // and all that other DB code... 19:                 ... 20:             } 21:             22:             timer.Stop(); 23:             24:             if (timer.ElapsedMilliseconds > 5000) 25:             { 26:                 _log.WarnFormat("Long query in GetAvailableProducts() took {0} ms", 27:                     timer.ElapsedMillseconds); 28:             } 29:             30:             return results; 31:         } 32:     } In my eye, this is very ugly.  It violates Single Responsibility Principle (SRP), which says that a class should only ever have one responsibility, where responsibility is often defined as a reason to change.  This class (and in particular this method) has two reasons to change: If the method of retrieving products changes. If the method of logging changes. Well, we could “simplify” this using the Decorator Design Pattern (here).  If we followed the pattern to the letter, we'd need to create a base decorator that implements the DAOs public interface and forwards to the wrapped instance.  So let's assume we break out the ProductDAO interface into IProductDAO using your refactoring tool of choice (Resharper is great for this). Now, ProductDao will implement IProductDao and get rid of all logging logic: 1:     public class ProductDao : IProductDao 2:     { 3:         // this reverts back to original version except for the interface added 4:     } 5:  And we create the base Decorator that also implements the interface and forwards all calls: 1:     public class ProductDaoDecorator : IProductDao 2:     { 3:         private readonly IProductDao _wrappedDao; 4:         5:         // constructor takes the dao to wrap 6:         public ProductDaoDecorator(IProductDao wrappedDao) 7:         { 8:             _wrappedDao = wrappedDao; 9:         } 10:         11:         ... 12:         13:         // and then all methods just forward their calls 14:         public IEnumerable<Product> GetAvailableProducts() 15:         { 16:             return _wrappedDao.GetAvailableProducts(); 17:         } 18:     } This defines our base decorator, then we can create decorators that add items of interest, and for any methods we don't decorate, we'll get the default behavior which just forwards the call to the wrapper in the base decorator: 1:     public class TimedThresholdProductDaoDecorator : ProductDaoDecorator 2:     { 3:         private static readonly ILog _log = LogManager.GetLogger(typeof(TimedThresholdProductDaoDecorator)); 4:         5:         public TimedThresholdProductDaoDecorator(IProductDao wrappedDao) : 6:             base(wrappedDao) 7:         { 8:         } 9:         10:         ... 11:         12:         public IEnumerable<Product> GetAvailableProducts() 13:         { 14:             var timer = Stopwatch.StartNew(); 15:             16:             var results = _wrapped.GetAvailableProducts(); 17:             18:             timer.Stop(); 19:             20:             if (timer.ElapsedMilliseconds > 5000) 21:             { 22:                 _log.WarnFormat("Long query in GetAvailableProducts() took {0} ms", 23:                     timer.ElapsedMillseconds); 24:             } 25:             26:             return results; 27:         } 28:     } Well, it's a bit better.  Now the logging is in its own class, and the database logic is in its own class.  But we've essentially multiplied the number of classes.  We now have 3 classes and one interface!  Now if you want to do that same logging decorating on all your DAOs, imagine the code bloat!  Sure, you can simplify and avoid creating the base decorator, or chuck it all and just inherit directly.  But regardless all of these have the problem of tying the logging logic into the code itself. Enter the Interceptors.  Things like this to me are a perfect example of when it's good to write an Interceptor using your class library of choice.  Sure, you could design your own perfectly generic decorator with delegates and all that, but personally I'm a big fan of Castle's Dynamic Proxy (here) which is actually used by many projects including Moq. What DynamicProxy allows you to do is intercept calls into any object by wrapping it with a proxy on the fly that intercepts the method and allows you to add functionality.  Essentially, the code would now look like this using DynamicProxy: 1: // Note: I like hiding DynamicProxy behind the scenes so users 2: // don't have to explicitly add reference to Castle's libraries. 3: public static class TimeThresholdInterceptor 4: { 5: // Our logging handle 6: private static readonly ILog _log = LogManager.GetLogger(typeof(TimeThresholdInterceptor)); 7:  8: // Handle to Castle's proxy generator 9: private static readonly ProxyGenerator _generator = new ProxyGenerator(); 10:  11: // generic form for those who prefer it 12: public static object Create<TInterface>(object target, TimeSpan threshold) 13: { 14: return Create(typeof(TInterface), target, threshold); 15: } 16:  17: // Form that uses type instead 18: public static object Create(Type interfaceType, object target, TimeSpan threshold) 19: { 20: return _generator.CreateInterfaceProxyWithTarget(interfaceType, target, 21: new TimedThreshold(threshold, level)); 22: } 23:  24: // The interceptor that is created to intercept the interface calls. 25: // Hidden as a private inner class so not exposing Castle libraries. 26: private class TimedThreshold : IInterceptor 27: { 28: // The threshold as a positive timespan that triggers a log message. 29: private readonly TimeSpan _threshold; 30:  31: // interceptor constructor 32: public TimedThreshold(TimeSpan threshold) 33: { 34: _threshold = threshold; 35: } 36:  37: // Intercept functor for each method invokation 38: public void Intercept(IInvocation invocation) 39: { 40: // time the method invocation 41: var timer = Stopwatch.StartNew(); 42:  43: // the Castle magic that tells the method to go ahead 44: invocation.Proceed(); 45:  46: timer.Stop(); 47:  48: // check if threshold is exceeded 49: if (timer.Elapsed > _threshold) 50: { 51: _log.WarnFormat("Long execution in {0} took {1} ms", 52: invocation.Method.Name, 53: timer.ElapsedMillseconds); 54: } 55: } 56: } 57: } Yes, it's a bit longer, but notice that: This class ONLY deals with logging long method calls, no DAO interface leftovers. This class can be used to time ANY class that has an interface or virtual methods. Personally, I like to wrap and hide the usage of DynamicProxy and IInterceptor so that anyone who uses this class doesn't need to know to add a Castle library reference.  As far as they are concerned, they're using my interceptor.  If I change to a new library if a better one comes along, they're insulated. Now, all we have to do to use this is to tell it to wrap our ProductDao and it does the rest: 1: // wraps a new ProductDao with a timing interceptor with a threshold of 5 seconds 2: IProductDao dao = TimeThresholdInterceptor.Create<IProductDao>(new ProductDao(), 5000); Automatic decoration of all methods!  You can even refine the proxy so that it only intercepts certain methods. This is ideal for so many things.  These are just some of the interceptors we've dreamed up and use: Log parameters and returns of methods to XML for auditing. Block invocations to methods and return default value (stubbing). Throw exception if certain methods are called (good for blocking access to deprecated methods). Log entrance and exit of a method and the duration. Log a message if a method takes more than a given time threshold to execute. Whether you use DynamicProxy or some other technology, I hope you see the benefits this adds.  Does it completely eliminate all need for the Decorator pattern?  No, there may still be cases where you want to decorate a particular class with functionality that doesn't apply to the world at large. But for all those cases where you are using Decorator to add functionality that's truly generic.  I strongly suggest you give this a try!

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• Évènement : eMetrics Marketing Optimization Summit, le salon de l'optimisation marketing et de la Bu

  eMetrics Marketing Optimization / SMX - l'événement webmarketing à ne pas manquer La première en France et ce sera au Hilton à Paris le 15 et 16 juin Le sommet eMetrics Marketing Optimization - l´évènement international de référence pour l´e-marketing et le « Web Analytics » - fera son entrée en France, pour la première fois le 15 et 16 juin 2010 à Paris. Depuis 2002, c´est la plateforme de rencontre des responsables marketing, des analystes web et des experts en business intelligence qui souhaitent augmenter leur retour sur investissements en ligne. Il est généralement mené en parallèle avec

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• Best in-memory cache of DB objects for Silverlight [closed]

  - by Jon

  Hi, I'd like to set up a cache of database objects (i.e. rows in a table) in memory in silverlight, which I'll do using WCF and linq-to-sql. Once I have the objects in memory, I'm planning on using MSMQ to receive new objects whenever they have been modified. It's a somewhat complex approach but the goal is to reduce trips to the database and allow instant data communication between Silverlight applications that are connected to the MSMQ. My Silverlight applications are meant to be long-running and the amount of data to be cached will not be large. I'm planning on saving the in-memory cache using local storage. Anyway, in order to process the updated objects that come in, I'd like to know if the user has changed the existing object. Could I use some event relating to data-binding to set a flag indicating that the object has changes? Maybe there's a better way to do the cache entirely? Thanks!

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• Search and Browse Database Objects with Oracle SQL Developer

  - by thatjeffsmith

  I was tempted to throw in another Dora the Explorer Map reference here, but I came to my senses.Having trouble finding something? Maybe you’re just getting older? I know I am. But still, it’d be nice if my favorite database tool could help me out a bit. Hmmm, what’s this ‘Find Database Object‘ thing over here…sounds like a search mechanism of some sort? You can access this panel from the ‘View‘ menu. It’s a good bit down the screen, so I don’t blame you if you haven’t seen it before. It makes finding ‘stuff’ in your database so much easier. Let’s say I want to find my ‘beer’ objects. I simply need to type my search string and the context (in this case I want it to search EVERYTHING), and hit enter. The search results are listed below and clicking on an object automatically opens it! I know it seems very simple, but I get asked this question a LOT. It will even search through your PL/SQL code! Finding too much? Be sure to toggle off the ‘%’ wildcard check box before doing a search. Working on a Project? I bet you use common column names, or codes, throughout your tables. You could take advantage of this knowledge and use the Find Database Object panel as a substitute connection tree or schema browser. Working on your HR project and want to look at your employee objects? Do a column search for your column ID/key. Sometimes thinking outside the box actually works! Don’t be afraid to tackle a problem from a weird angle, or re-purpose your tools. I do it all the time And I drive the developers nuts trying to do things with the tools they were never designed to do. But I digress. Back to your coding!

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• Oracle Technológia Fórum rendezvény, 2010. május 5. szerda

  - by Fekete Zoltán

  Jövo hét szerdán Oracle Technology Fórum napot tartunk, ahol az adatbázis-kezelési és a fejlesztoi szekciókban hallgathatók meg eloadások illetve kaphatók válaszok a kérdésekre. Jelentkezés a rendezvényre. Az adatbázis szekcióban fogok beszélni a Sun Oracle Database Machine / Exadata megoldások technikai gyöngyszemeirol mind a tranzakciós (OLTP) mind az adattárházas (DW) és adatbázis konszolidáció oldaláról. Emellett kiemelem majd az Oracle Data Mining (adatbányászat) és OLAP újdonságait, érdekességeit. Megemlítem majd az Oracle's Data Warehouse Reference Architecture alkalmazási lehetoségeit is.

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• Why is String Templating Better Than String Concatenation from an Engineering Perspective?

  - by stephen

  I once read (I think it was in "Programming Pearls") that one should use templates instead of building the string through the use of concatenation. For example, consider the template below (using C# razor library) <in a properties file> Browser Capabilities Type = @Model.Type Name = @Model.Browser Version = @Model.Version Supports Frames = @Model.Frames Supports Tables = @Model.Tables Supports Cookies = @Model.Cookies Supports VBScript = @Model.VBScript Supports Java Applets = @Model.JavaApplets Supports ActiveX Controls = @Model.ActiveXControls and later, in a separate code file private void Button1_Click(object sender, System.EventArgs e) { BrowserInfoTemplate = Properties.Resources.browserInfoTemplate; // see above string browserInfo = RazorEngine.Razor.Parse(BrowserInfoTemplate, browser); ... } From a software engineering perspective, how is this better than an equivalent string concatentation, like below: private void Button1_Click(object sender, System.EventArgs e) { System.Web.HttpBrowserCapabilities browser = Request.Browser; string s = "Browser Capabilities\n" + "Type = " + browser.Type + "\n" + "Name = " + browser.Browser + "\n" + "Version = " + browser.Version + "\n" + "Supports Frames = " + browser.Frames + "\n" + "Supports Tables = " + browser.Tables + "\n" + "Supports Cookies = " + browser.Cookies + "\n" + "Supports VBScript = " + browser.VBScript + "\n" + "Supports JavaScript = " + browser.EcmaScriptVersion.ToString() + "\n" + "Supports Java Applets = " + browser.JavaApplets + "\n" + "Supports ActiveX Controls = " + browser.ActiveXControls + "\n" ... }

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• SQL SERVER – Weekly Series – Memory Lane – #035

  - by Pinal Dave

  Here is the list of selected articles of SQLAuthority.com across all these years. Instead of just listing all the articles I have selected a few of my most favorite articles and have listed them here with additional notes below it. Let me know which one of the following is your favorite article from memory lane. 2007 Row Overflow Data Explanation  In SQL Server 2005 one table row can contain more than one varchar(8000) fields. One more thing, the exclusions has exclusions also the limit of each individual column max width of 8000 bytes does not apply to varchar(max), nvarchar(max), varbinary(max), text, image or xml data type columns. Comparison Index Fragmentation, Index De-Fragmentation, Index Rebuild – SQL SERVER 2000 and SQL SERVER 2005 An old but like a gold article. Talks about lots of concepts related to Index and the difference from earlier version to the newer version. I strongly suggest that everyone should read this article just to understand how SQL Server has moved forward with the technology. Improvements in TempDB SQL Server 2005 had come up with quite a lots of improvements and this blog post describes them and explains the same. If you ask me what is my the most favorite article from early career. I must point out to this article as when I wrote this one I personally have learned a lot of new things. Recompile All The Stored Procedure on Specific TableI prefer to recompile all the stored procedure on the table, which has faced mass insert or update. sp_recompiles marks stored procedures to recompile when they execute next time. This blog post explains the same with the help of a script.  2008 SQLAuthority Download – SQL Server Cheatsheet You can download and print this cheat sheet and use it for your personal reference. If you have any suggestions, please let me know and I will see if I can update this SQL Server cheat sheet. Difference Between DBMS and RDBMS What is the difference between DBMS and RDBMS? DBMS – Data Base Management System RDBMS – Relational Data Base Management System or Relational DBMS High Availability – Hot Add Memory Hot Add CPU and Hot Add Memory are extremely interesting features of the SQL Server, however, personally I have not witness them heavily used. These features also have few restriction as well. I blogged about them in detail. 2009 Delete Duplicate Rows I have demonstrated in this blog post how one can identify and delete duplicate rows. Interesting Observation of Logon Trigger On All Servers – Solution The question I put forth in my previous article was – In single login why the trigger fires multiple times; it should be fired only once. I received numerous answers in thread as well as in my MVP private news group. Now, let us discuss the answer for the same. The answer is – It happens because multiple SQL Server services are running as well as intellisense is turned on. Blog post demonstrates how we can do the same with the help of SQL scripts. Management Studio New Features I have selected my favorite 5 features and blogged about it. IntelliSense for Query Editing Multi Server Query Query Editor Regions Object Explorer Enhancements Activity Monitors Maximum Number of Index per Table One of the questions I asked in my user group was – What is the maximum number of Index per table? I received lots of answers to this question but only two answers are correct. Let us now take a look at them in this blog post. 2010 Default Statistics on Column – Automatic Statistics on Column The truth is, Statistics can be in a table even though there is no Index in it. If you have the auto- create and/or auto-update Statistics feature turned on for SQL Server database, Statistics will be automatically created on the Column based on a few conditions. Please read my previously posted article, SQL SERVER – When are Statistics Updated – What triggers Statistics to Update, for the specific conditions when Statistics is updated. 2011 T-SQL Scripts to Find Maximum between Two Numbers In this blog post there are two different scripts listed which demonstrates way to find the maximum number between two numbers. I need your help, which one of the script do you think is the most accurate way to find maximum number? Find Details for Statistics of Whole Database – DMV – T-SQL Script I was recently asked is there a single script which can provide all the necessary details about statistics for any database. This question made me write following script. I was initially planning to use sp_helpstats command but I remembered that this is marked to be deprecated in future. 2012 Introduction to Function SIGN SIGN Function is very fundamental function. It will return the value 1, -1 or 0. If your value is negative it will return you negative -1 and if it is positive it will return you positive +1. Let us start with a simple small example. Template Browser – A Very Important and Useful Feature of SSMS Templates are like a quick cheat sheet or quick reference. Templates are available to create objects like databases, tables, views, indexes, stored procedures, triggers, statistics, and functions. Templates are also available for Analysis Services as well. The template scripts contain parameters to help you customize the code. You can Replace Template Parameters dialog box to insert values into the script. An invalid floating point operation occurred If you run any of the above functions they will give you an error related to invalid floating point. Honestly there is no workaround except passing the function appropriate values. SQRT of a negative number will give you result in real numbers which is not supported at this point of time as well LOG of a negative number is not possible (because logarithm is the inverse function of an exponential function and the exponential function is NEVER negative). Validating Spatial Object with IsValidDetailed Function SQL Server 2012 has introduced the new function IsValidDetailed(). This function has made my life very easy. In simple words, this function will check if the spatial object passed is valid or not. If it is valid it will give information that it is valid. If the spatial object is not valid it will return the answer that it is not valid and the reason for the same. This makes it very easy to debug the issue and make the necessary correction. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Memory Lane, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• SQLAuthority News – New Book Released – SQL Server Interview Questions And Answers

  - by pinaldave

  Two days ago, on birthday of my blog – I asked simple question – Guess! What is in this box? I have received lots of interesting comments on the blog about what is in it. Many of you got it absolutely incorrect and many got it close to the right answer but no one got it 100% correct. Well, no issue at all, I am going to give away the price to whoever has the closest answer first in personal email. Here is the answer to the question about what is in the box? Here it is – the box has my new book. In fact, I should say our new book as I co-authored this book with my very good friend Vinod Kumar. We had real blast writing this book together and had lots of interesting conversation when we were writing this book. This book has one simple goal – “master the basics.” This book is not only for people who are preparing for interview. This book is for every one who wants to revisit the basics and wants to prepare themselves to the technology. One always needs to have practical knowledge to do their duty efficiently. This book talks about more than basics. There are multiple ways to present learning – either we can create simple book or make it interesting. We have decided the learning should be interactive and have opted for Interview Questions and Answer format. Here is quick interview which we have done together. Details of the books are here The core concept of this book will continue to evolve over time. I am sure many of you will come along with us on this journey and submit your suggestions to us to make this book a key reference for anybody who wants to start with SQL server. Today we want to acknowledge the fact that you will help us keep this book alive forever with the latest updates. We want to thank everyone who participates in this journey with us. You can get the books from [Amazon] | [Flipkart]. Read Vinod‘s blog post. Do not forget to wish him happy birthday as today is his birthday and also book release day – two reason to wish him congratulations. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: Best Practices, Data Warehousing, Database, Pinal Dave, PostADay, SQL, SQL Authority, SQL Interview Questions and Answers, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority Book Review, SQLAuthority News, SQLServer, T SQL, Technology

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• How to Achieve OC4J RMI Load Balancing

  - by fip

  This is an old, Oracle SOA and OC4J 10G topic. In fact this is not even a SOA topic per se. Questions of RMI load balancing arise when you developed custom web applications accessing human tasks running off a remote SOA 10G cluster. Having returned from a customer who faced challenges with OC4J RMI load balancing, I felt there is still some confusions in the field how OC4J RMI load balancing work. Hence I decide to dust off an old tech note that I wrote a few years back and share it with the general public. Here is the tech note: Overview A typical use case in Oracle SOA is that you are building web based, custom human tasks UI that will interact with the task services housed in a remote BPEL 10G cluster. Or, in a more generic way, you are just building a web based application in Java that needs to interact with the EJBs in a remote OC4J cluster. In either case, you are talking to an OC4J cluster as RMI client. Then immediately you must ask yourself the following questions: 1. How do I make sure that the web application, as an RMI client, even distribute its load against all the nodes in the remote OC4J cluster? 2. How do I make sure that the web application, as an RMI client, is resilient to the node failures in the remote OC4J cluster, so that in the unlikely case when one of the remote OC4J nodes fail, my web application will continue to function? That is the topic of how to achieve load balancing with OC4J RMI client. Solutions You need to configure and code RMI load balancing in two places: 1. Provider URL can be specified with a comma separated list of URLs, so that the initial lookup will land to one of the available URLs. 2. Choose a proper value for the oracle.j2ee.rmi.loadBalance property, which, along side with the PROVIDER_URL property, is one of the JNDI properties passed to the JNDI lookup.(http://docs.oracle.com/cd/B31017_01/web.1013/b28958/rmi.htm#BABDGFBI) More details below: About the PROVIDER_URL The JNDI property java.name.provider.url's job is, when the client looks up for a new context at the very first time in the client session, to provide a list of RMI context The value of the JNDI property java.name.provider.url goes by the format of a single URL, or a comma separate list of URLs. A single URL. For example: opmn:ormi://host1:6003:oc4j_instance1/appName1 A comma separated list of multiple URLs. For examples:  opmn:ormi://host1:6003:oc4j_instanc1/appName, opmn:ormi://host2:6003:oc4j_instance1/appName, opmn:ormi://host3:6003:oc4j_instance1/appName When the client looks up for a new Context the very first time in the client session, it sends a query against the OPMN referenced by the provider URL. The OPMN host and port specifies the destination of such query, and the OC4J instance name and appName are actually the “where clause” of the query. When the PROVIDER URL reference a single OPMN server Let's consider the case when the provider url only reference a single OPMN server of the destination cluster. In this case, that single OPMN server receives the query and returns a list of the qualified Contexts from all OC4Js within the cluster, even though there is a single OPMN server in the provider URL. A context represent a particular starting point at a particular server for subsequent object lookup. For example, if the URL is opmn:ormi://host1:6003:oc4j_instance1/appName, then, OPMN will return the following contexts: appName on oc4j_instance1 on host1 appName on oc4j_instance1 on host2, appName on oc4j_instance1 on host3,  (provided that host1, host2, host3 are all in the same cluster) Please note that One OPMN will be sufficient to find the list of all contexts from the entire cluster that satisfy the JNDI lookup query. You can do an experiment by shutting down appName on host1, and observe that OPMN on host1 will still be able to return you appname on host2 and appName on host3. When the PROVIDER URL reference a comma separated list of multiple OPMN servers When the JNDI propery java.naming.provider.url references a comma separated list of multiple URLs, the lookup will return the exact same things as with the single OPMN server: a list of qualified Contexts from the cluster. The purpose of having multiple OPMN servers is to provide high availability in the initial context creation, such that if OPMN at host1 is unavailable, client will try the lookup via OPMN on host2, and so on. After the initial lookup returns and cache a list of contexts, the JNDI URL(s) are no longer used in the same client session. That explains why removing the 3rd URL from the list of JNDI URLs will not stop the client from getting the EJB on the 3rd server. About the oracle.j2ee.rmi.loadBalance Property After the client acquires the list of contexts, it will cache it at the client side as “list of available RMI contexts”.  This list includes all the servers in the destination cluster. This list will stay in the cache until the client session (JVM) ends. The RMI load balancing against the destination cluster is happening at the client side, as the client is switching between the members of the list. Whether and how often the client will fresh the Context from the list of Context is based on the value of the  oracle.j2ee.rmi.loadBalance. The documentation at http://docs.oracle.com/cd/B31017_01/web.1013/b28958/rmi.htm#BABDGFBI list all the available values for the oracle.j2ee.rmi.loadBalance. Value Description client If specified, the client interacts with the OC4J process that was initially chosen at the first lookup for the entire conversation. context Used for a Web client (servlet or JSP) that will access EJBs in a clustered OC4J environment. If specified, a new Context object for a randomly-selected OC4J instance will be returned each time InitialContext() is invoked. lookup Used for a standalone client that will access EJBs in a clustered OC4J environment. If specified, a new Context object for a randomly-selected OC4J instance will be created each time the client calls Context.lookup(). Please note the regardless of the setting of oracle.j2ee.rmi.loadBalance property, the “refresh” only occurs at the client. The client can only choose from the "list of available context" that was returned and cached from the very first lookup. That is, the client will merely get a new Context object from the “list of available RMI contexts” from the cache at the client side. The client will NOT go to the OPMN server again to get the list. That also implies that if you are adding a node to the server cluster AFTER the client’s initial lookup, the client would not know it because neither the server nor the client will initiate a refresh of the “list of available servers” to reflect the new node. About High Availability (i.e. Resilience Against Node Failure of Remote OC4J Cluster) What we have discussed above is about load balancing. Let's also discuss high availability. This is how the High Availability works in RMI: when the client use the context but get an exception such as socket is closed, it knows that the server referenced by that Context is problematic and will try to get another unused Context from the “list of available contexts”. Again, this list is the list that was returned and cached at the very first lookup in the entire client session.

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• Automating SQL Execution Plan analysis

  - by jchang

  Last year, I made my tool for automating execution plan analysis available on www.qdpma.com The original version could parse execution plans from sys.dm_exec_query_stats or dm_exec_cached_plans and generate a cross-reference of which execution plans employed each index. The DMV sys.dm_db_index_usage_stats shows how often each index is used, but not where, that is, which particular stored procedure or My latest version can now also 1) use the DMV sys.dm_exec_procedure_stats, 2) it can also get the...(read more)

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• How to have other divs with a flash liquid layout that fits to the page?

  - by brybam

  Basically the majority of my content is flash based. I designed it using Flash Builder (Flex) and Its in a liquid layout, (everything is in percents) and if im JUST embedding the flash content it scales to the page fine, and i have the flash content set to have a padding of 50 px. I put a header div in fine with no problems, but I have 2 problems, the first being the footer div seems to cover up the buttom of the flash content in IE, but it looks just fine in chrome. How can I solve this? I'm using the stock embed code that Flex provides, I tried to edit the css style for the div which I think is #flashContent and give it a min width and min height but it didnt seem to work, actually anything I did to #flashContent didn't seem to do anything, maybe its not the div i need to be adding that attribute to... And my other problem is I dont even know where to start when it comes to placing a div thats 280width by 600height colum to the right side of the flash content. If i could specify a size for the flash content, and the float it left, and float the colum right, and clear it with the container div id be just fine....But remember the flash content is set to 100% Scale (well techically 100%x80% because it looked better that way). Does anyone know how I can start to deal with creating a more complex scaleable flash layouts that includes other divs? ALL WELL MAINTAINING IE SUPPORT? IE is ruining my life. Here's the code I'm using: (or if it will help you visualize what im trying to do here's the page where im working on setting this up http://apumpkinpatch.com/textmashnew/) <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en"> <head> <title>TextMixup</title> <meta name="google" value="notranslate"> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <link href="css.css" rel="stylesheet" type="text/css" /> <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.5.2/jquery.min.js"></script> <script src="../appassets/scripts/jquery.titlealert.js"></script> <script type="text/javascript"> var _gaq = _gaq || []; _gaq.push(['_setAccount', 'UA-19768131-2']); _gaq.push(['_trackPageview']); (function() { var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true; ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s); })(); function tabNotification() { $.titleAlert('New Message!', {interval:200,requireBlur:true,stopOnFocus:true}); } function joinNotification() { $.titleAlert('Joined Chat!', {interval:200,requireBlur:true,stopOnFocus:true}); } </script> <!-- BEGIN Browser History required section --> <link rel="stylesheet" type="text/css" href="history/history.css" /> <script type="text/javascript" src="history/history.js"></script> <!-- END Browser History required section --> <script type="text/javascript" src="swfobject.js"></script> <script type="text/javascript"> var swfVersionStr = "10.2.0"; var xiSwfUrlStr = "playerProductInstall.swf"; var flashvars = {}; var params = {}; params.quality = "high"; params.bgcolor = "#ffffff"; params.allowscriptaccess = "sameDomain"; params.allowfullscreen = "true"; var attributes = {}; attributes.id = "TextMixup"; attributes.name = "TextMixup"; attributes.align = "middle"; swfobject.embedSWF( "TextMixup.swf", "flashContent", "100%", "80%", swfVersionStr, xiSwfUrlStr, flashvars, params, attributes); swfobject.createCSS("#flashContent", "display:block;text-align:left;"); </script> </head> <body> <div id="homebar"><a href="http://apumpkinpatch.com"><img src="../appassets/images/logo/logoHor_130_30.png" alt="APumpkinPatch HOME" width="130" height="30" hspace="10" vspace="3" border="0"/></a> </div> <div id="topad"> <script type="text/javascript"><!-- google_ad_client = "pub-5824388356626461"; /* 728x90, textmash */ google_ad_slot = "1114351240"; google_ad_width = 728; google_ad_height = 90; //--> </script> <script type="text/javascript" src="http://pagead2.googlesyndication.com/pagead/show_ads.js"> </script> </div> <div id="mainContainer"> <div id="flashContent"> <p> To view this page ensure that Adobe Flash Player version 10.2.0 or greater is installed. </p> <script type="text/javascript"> var pageHost = ((document.location.protocol == "https:") ? "https://" : "http://"); document.write("<a href='http://www.adobe.com/go/getflashplayer'><img src='" + pageHost + "www.adobe.com/images/shared/download_buttons/get_flash_player.gif' alt='Get Adobe Flash player' /></a>" ); </script> </div> <noscript> <object classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000" width="100%" height="80%" id="TextMixup"> <param name="movie" value="TextMixup.swf" /> <param name="quality" value="high" /> <param name="bgcolor" value="#ffffff" /> <param name="allowScriptAccess" value="sameDomain" /> <param name="allowFullScreen" value="true" /> <!--[if !IE]>--> <object type="application/x-shockwave-flash" data="TextMixup.swf" width="100%" height="80%"> <param name="quality" value="high" /> <param name="bgcolor" value="#ffffff" /> <param name="allowScriptAccess" value="sameDomain" /> <param name="allowFullScreen" value="true" /> <!--<![endif]--> <!--[if gte IE 6]>--> <p> Either scripts and active content are not permitted to run or Adobe Flash Player version 10.2.0 or greater is not installed. </p> <!--<![endif]--> <a href="http://www.adobe.com/go/getflashplayer"> <img src="http://www.adobe.com/images/shared/download_buttons/get_flash_player.gif" alt="Get Adobe Flash Player" /> </a> <!--[if !IE]>--> </object> <!--<![endif]--> </object> </noscript> <div id="convosPreview">This is a div I would want to appear as a colum to the right of the flash content that can scale</div> <!---End mainContainer --> </div> <div id="footer"> <a href="../apps.html"><img src="../appassets/images/apps.png" hspace="5" vspace="5" alt="random chat app apumpkinpatch" width="228" height="40" border="0" /></a><a href="https://chrome.google.com/webstore/detail/hjmnobclpbhnjcpdnpdnkbgdkbfifbao?hl=en-US#"><img src="../appassets/images/chromeapp.png" alt="chrome app random video chat apumpkinpatch" width="115" height="40" vspace="5" border="0" /></a><br /><br /> <a href="http://spacebarup.com" target="_blank">©2011 Space Bar</a> | <a href="../tos.html">TOS & Privacy Policy</a> | <a href="../help.html">FAQ & Help</a> | <a href="../tips.html">Important online safety tips</a> | <a href="http://www.facebook.com/pages/APumpkinPatchcom/164279206963001?sk=app_2373072738" target="_blank">Discussion Boards</a><br /> <p>You must be at least 18 years of age to access this web site.<br />APumpkinPatch.com is not responsible for the actions of any visitors of this site.<br />APumpkinPatch.com does not endorse or claim ownership to any of the content that is broadcast through this site. </p><h2>A Pumpkin Patch is BRAND NEW and will be developed a lot over the next few months adding video chat games, chat rooms, and more! Check back often it's going to be a lot of fun!</h2> </div> </body> </html> myCSS: html, body { height:100%; } body { text-align:center; font-family: Helvetica, Arial, sans-serif; margin:0; padding:0; overflow:auto; text-align:center; background-color: #ffffff; } object:focus { outline:none; } #homebar { clear:both; text-align: left; width: 100%; height: 40px; background-color:#333333; color:#CCC; overflow:hidden; box-shadow: 0px 0px 14px rgba(0, 0, 0, 0.65); -moz-box-shadow: 0px 0px 14px rgba(0, 0, 0, 0.65); -webkit-box-shadow: 0px 0px 14px rgba(0, 0, 0, 0.65); margin-bottom: 10px; } #mainContainer { height:auto; width:auto; clear:both; } #flashContent { display:none; height:auto; float:left; min-height: 500px; min-width: 340px; } /**this is the div i want to appear as a column net to the scaleable flash content **/ #convosPreview { float:right; width:280px; height:600px; }

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• Guest Post: Using IronRuby and .NET to produce the &lsquo;Hello World of WPF&rsquo;

  - by Eric Nelson

  [You might want to also read other GuestPosts on my blog – or contribute one?] On the 26th and 27th of March (2010) myself and Edd Morgan of Microsoft will be popping along to the Scottish Ruby Conference. I dabble with Ruby and I am a huge fan whilst Edd is a “proper Ruby developer”. Hence I asked Edd if he was interested in creating a guest post or two for my blog on IronRuby. This is the second of those posts. If you should stumble across this post and happen to be attending the Scottish Ruby Conference, then please do keep a look out for myself and Edd. We would both love to chat about all things Ruby and IronRuby. And… we should have (if Amazon is kind) a few books on IronRuby with us at the conference which will need to find a good home. This is me and Edd and … the book: Order on Amazon: http://bit.ly/ironrubyunleashed Using IronRuby and .NET to produce the ‘Hello World of WPF’ In my previous post I introduced, to a minor extent, IronRuby. I expanded a little on the basics of by getting a Rails app up-and-running on this .NET implementation of the Ruby language — but there wasn't much to it! So now I would like to go from simply running a pre-existing project under IronRuby to developing a whole new application demonstrating the seamless interoperability between IronRuby and .NET. In particular, we'll be using WPF (Windows Presentation Foundation) — the component of the .NET Framework stack used to create rich media and graphical interfaces. Foundations of WPF To reiterate, WPF is the engine in the .NET Framework responsible for rendering rich user interfaces and other media. It's not the only collection of libraries in the framework with the power to do this — Windows Forms does the trick, too — but it is the most powerful and flexible. Put simply, WPF really excels when you need to employ eye candy. It's all about creating impact. Whether you're presenting a document, video, a data entry form, some kind of data visualisation (which I am most hopeful for, especially in terms of IronRuby - more on that later) or chaining all of the above with some flashy animations, you're likely to find that WPF gives you the most power when developing any of these for a Windows target. Let's demonstrate this with an example. I give you what I like to consider the 'hello, world' of WPF applications: the analogue clock. Today, over my lunch break, I created a WPF-based analogue clock using IronRuby... Any normal person would have just looked at their watch. - Twitter The Sample Application: Click here to see this sample in full on GitHub. Using Windows Presentation Foundation from IronRuby to create a Clock class Invoking the Clock class   Gives you The above is by no means perfect (it was a lunch break), but I think it does the job of illustrating IronRuby's interoperability with WPF using a familiar data visualisation. I'm sure you'll want to dissect the code yourself, but allow me to step through the important bits. (By the way, feel free to run this through ir first to see what actually happens). Now we're using IronRuby - unlike my previous post where we took pure Ruby code and ran it through ir, the IronRuby interpreter, to demonstrate compatibility. The main thing of note is the very distinct parallels between .NET namespaces and Ruby modules, .NET classes and Ruby classes. I guess there's not much to say about it other than at this point, you may as well be working with a purely Ruby graphics-drawing library. You're instantiating .NET objects, but you're doing it with the standard Ruby .new method you know from Ruby as Object#new — although, the root object of all your IronRuby objects isn't actually Object, it's System.Object. You're calling methods on these objects (and classes, for example in the call to System.Windows.Controls.Canvas.SetZIndex()) using the underscored, lowercase convention established for the Ruby language. The integration is so seamless. The fact that you're using a dynamic language on top of .NET's CLR is completely abstracted from you, allowing you to just build your software. A Brief Note on Events Events are a big part of developing client applications in .NET as well as under every other environment I can think of. In case you aren't aware, event-driven programming is essentially the practice of telling your code to call a particular method, or other chunk of code (a delegate) when something happens at an unpredictable time. You can never predict when a user is going to click a button, move their mouse or perform any other kind of input, so the advent of the GUI is what necessitated event-driven programming. This is where one of my favourite aspects of the Ruby language, blocks, can really help us. In traditional C#, for instance, you may subscribe to an event (assign a block of code to execute when an event occurs) in one of two ways: by passing a reference to a named method, or by providing an anonymous code block. You'd be right for seeing the parallel here with Ruby's concept of blocks, Procs and lambdas. As demonstrated at the very end of this rather basic script, we are using .NET's System.Timers.Timer to (attempt to) update the clock every second (I know it's probably not the best way of doing this, but for example's sake). Note: Diverting a little from what I said above, the ticking of a clock is very predictable, yet we still use the event our Timer throws to do this updating as one of many ways to perform that task outside of the main thread. You'll see that all that's needed to assign a block of code to be triggered on an event is to provide that block to the method of the name of the event as it is known to the CLR. This drawback to this is that it only allows the delegation of one code block to each event. You may use the add method to subscribe multiple handlers to that event - pushing that to the end of a queue. Like so: def tick puts "tick tock" end timer.elapsed.add method(:tick) timer.elapsed.add proc { puts "tick tock" } tick_handler = lambda { puts "tick tock" } timer.elapsed.add(tick_handler)   The ability to just provide a block of code as an event handler helps IronRuby towards that very important term I keep throwing around; low ceremony. Anonymous methods are, of course, available in other more conventional .NET languages such as C# and VB but, as usual, feel ever so much more elegant and natural in IronRuby. Note: Whether it's a named method or an anonymous chunk o' code, the block you delegate to the handling of an event can take arguments - commonly, a sender object and some args. Another Brief Note on Verbosity Personally, I don't mind verbose chaining of references in my code as long as it doesn't interfere with performance - as evidenced in the example above. While I love clean code, there's a certain feeling of safety that comes with the terse explicitness of long-winded addressing and the describing of objects as opposed to ambiguity (not unlike this sentence). However, when working with IronRuby, even I grow tired of typing System::Whatever::Something. Some people enjoy simply assuming namespaces and forgetting about them, regardless of the language they're using. Don't worry, IronRuby has you covered. It is completely possible to, with a call to include, bring the contents of a .NET-converted module into context of your IronRuby code - just as you would if you wanted to bring in an 'organic' Ruby module. To refactor the style of the above example, I could place the following at the top of my Clock class: class Clock include System::Windows::Shape include System::Windows::Media include System::Windows::Threading # and so on...   And by doing so, reduce calls to System::Windows::Shapes::Ellipse.new to simply Ellipse.new or references to System::Windows::Threading::DispatcherPriority.Render to a friendlier DispatcherPriority.Render. Conclusion I hope by now you can understand better how IronRuby interoperates with .NET and how you can harness the power of the .NET framework with the dynamic nature and elegant idioms of the Ruby language. The manner and parlance of Ruby that makes it a joy to work with sets of data is, of course, present in IronRuby — couple that with WPF's capability to produce great graphics quickly and easily, and I hope you can visualise the possibilities of data visualisation using these two things. Using IronRuby and WPF together to create visual representations of data and infographics is very exciting to me. Although today, with this project, we're only presenting one simple piece of information - the time - the potential is much grander. My day-to-day job is centred around software development and UI design, specifically in the realm of healthcare, and if you were to pay a visit to our office you would behold, directly above my desk, a large plasma TV with a constantly rotating, animated slideshow of charts and infographics to help members of our team do their jobs. It's an app powered by WPF which never fails to spark some conversation with visitors whose gaze has been hooked. If only it was written in IronRuby, the pleasantly low ceremony and reduced pre-processing time for my brain would have helped greatly. Edd Morgan blog Related Links: Getting PhP and Ruby working on Windows Azure and SQL Azure

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• Tutorial: Getting Started with the NoSQL JavaScript / Node.js API for MySQL Cluster

  - by Mat Keep

  Tutorial authored by Craig Russell and JD Duncan  The MySQL Cluster team are working on a new NoSQL JavaScript connector for MySQL. The objectives are simplicity and high performance for JavaScript users: - allows end-to-end JavaScript development, from the browser to the server and now to the world's most popular open source database - native "NoSQL" access to the storage layer without going first through SQL transformations and parsing. Node.js is a complete web platform built around JavaScript designed to deliver millions of client connections on commodity hardware. With the MySQL NoSQL Connector for JavaScript, Node.js users can easily add data access and persistence to their web, cloud, social and mobile applications. While the initial implementation is designed to plug and play with Node.js, the actual implementation doesn't depend heavily on Node, potentially enabling wider platform support in the future. Implementation The architecture and user interface of this connector are very different from other MySQL connectors in a major way: it is an asynchronous interface that follows the event model built into Node.js. To make it as easy as possible, we decided to use a domain object model to store the data. This allows for users to query data from the database and have a fully-instantiated object to work with, instead of having to deal with rows and columns of the database. The domain object model can have any user behavior that is desired, with the NoSQL connector providing the data from the database. To make it as fast as possible, we use a direct connection from the user's address space to the database. This approach means that no SQL (pun intended) is needed to get to the data, and no SQL server is between the user and the data. The connector is being developed to be extensible to multiple underlying database technologies, including direct, native access to both the MySQL Cluster "ndb" and InnoDB storage engines. The connector integrates the MySQL Cluster native API library directly within the Node.js platform itself, enabling developers to seamlessly couple their high performance, distributed applications with a high performance, distributed, persistence layer delivering 99.999% availability. The following sections take you through how to connect to MySQL, query the data and how to get started. Connecting to the database A Session is the main user access path to the database. You can get a Session object directly from the connector using the openSession function: var nosql = require("mysql-js"); var dbProperties = {     "implementation" : "ndb",     "database" : "test" }; nosql.openSession(dbProperties, null, onSession); The openSession function calls back into the application upon creating a Session. The Session is then used to create, delete, update, and read objects. Reading data The Session can read data from the database in a number of ways. If you simply want the data from the database, you provide a table name and the key of the row that you want. For example, consider this schema: create table employee (   id int not null primary key,   name varchar(32),   salary float ) ENGINE=ndbcluster; Since the primary key is a number, you can provide the key as a number to the find function. function onSession = function(err, session) {   if (err) {     console.log(err);     ... error handling   }   session.find('employee', 0, onData); }; function onData = function(err, data) {   if (err) {     console.log(err);     ... error handling   }   console.log('Found: ', JSON.stringify(data));   ... use data in application }; If you want to have the data stored in your own domain model, you tell the connector which table your domain model uses, by specifying an annotation, and pass your domain model to the find function. var annotations = new nosql.Annotations(); function Employee = function(id, name, salary) {   this.id = id;   this.name = name;   this.salary = salary;   this.giveRaise = function(percent) {     this.salary *= percent;   } }; annotations.mapClass(Employee, {'table' : 'employee'}); function onSession = function(err, session) {   if (err) {     console.log(err);     ... error handling   }   session.find(Employee, 0, onData); }; Updating data You can update the emp instance in memory, but to make the raise persistent, you need to write it back to the database, using the update function. function onData = function(err, emp) {   if (err) {     console.log(err);     ... error handling   }   console.log('Found: ', JSON.stringify(emp));   emp.giveRaise(0.12); // gee, thanks!   session.update(emp); // oops, session is out of scope here }; Using JavaScript can be tricky because it does not have the concept of block scope for variables. You can create a closure to handle these variables, or use a feature of the connector to remember your variables. The connector api takes a fixed number of parameters and returns a fixed number of result parameters to the callback function. But the connector will keep track of variables for you and return them to the callback. So in the above example, change the onSession function to remember the session variable, and you can refer to it in the onData function: function onSession = function(err, session) {   if (err) {     console.log(err);     ... error handling   }   session.find(Employee, 0, onData, session); }; function onData = function(err, emp, session) {   if (err) {     console.log(err);     ... error handling   }   console.log('Found: ', JSON.stringify(emp));   emp.giveRaise(0.12); // gee, thanks!   session.update(emp, onUpdate); // session is now in scope }; function onUpdate = function(err, emp) {   if (err) {     console.log(err);     ... error handling   } Inserting data Inserting data requires a mapped JavaScript user function (constructor) and a session. Create a variable and persist it: function onSession = function(err, session) {   var data = new Employee(999, 'Mat Keep', 20000000);   session.persist(data, onInsert);   } }; Deleting data To remove data from the database, use the session remove function. You use an instance of the domain object to identify the row you want to remove. Only the key field is relevant. function onSession = function(err, session) {   var key = new Employee(999);   session.remove(Employee, onDelete);   } }; More extensive queries We are working on the implementation of more extensive queries along the lines of the criteria query api. Stay tuned. How to evaluate The MySQL Connector for JavaScript is available for download from labs.mysql.com. Select the build: MySQL-Cluster-NoSQL-Connector-for-Node-js You can also clone the project on GitHub Since it is still early in development, feedback is especially valuable (so don't hesitate to leave comments on this blog, or head to the MySQL Cluster forum). Try it out and see how easy (and fast) it is to integrate MySQL Cluster into your Node.js platforms. You can learn more about other previewed functionality of MySQL Cluster 7.3 here

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• 5 Reasons why I hate WPF

  - by Richard Mitchell

  I decided to use writing a new tool as a way to learn WPF and MVVM and I thought I'd write down a few of my problems as a way of cathartic release. I decided to read a book before attempting WPF for the first time as I've heard others complain about the steep learning curve. I chose the rather excellent "WPF 4 Unleashed" by Adam Nathan to read through and "Pro WPF in C# 2010" by Matthew MacDonald as a reference whilst I programmed. 1 - Poor editing support for XAML The first thing I think any...(read more)

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• Flashing screen during videos and games

  - by Collif

  I recently switched from Vista to Ubuntu 12.10 on my HP laptop and I've been having issues with my graphics. Everything is fine till I watch a video/play a game or (sometimes) when I visit the software centre. At that point large portions of the screen start flashing and everything gets rather slow. I'm looking for a way to remedy this. For reference I'm using Firefox and I'm unsure what my video card is because it's listed as unknown when I check my system settings.

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• Download PowerCommands for VS 2008

  - by Editor

  PowerCommands is a set of useful extensions for the Visual Studio 2008 adding additional functionality to various areas of the IDE. The source code is included and requires the VS SDK for VS 2008 to allow modification of functionality or as a reference to create additional custom PowerCommand extensions. Visit the [...]

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• Learning Resources for SharePoint

  - by Enrique Lima

  SharePoint 2010 Reference: Software Development Kit SharePoint 2010: Getting Started with Development on SharePoint 2010 Hands-on Labs in C# and Visual Basic SharePoint Developer Training Kit Professional Development Evaluation Guide and Walkthrough SharePoint Server 2010: Advanced Developer Training Presentations

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• SQL SERVER – Difference Between CURRENT_TIMESTAMP and GETDATE() – CURRENT_TIMESTAMP Equivalent in SQL Server

  - by pinaldave

  A common question – I often get from Oracle/MySQL Professionals: “What is the Equivalent to CURRENT_TIMESTAMP in SQL Server?” Here is a common question I often get from SQL Server Professionals: “What are differences between Difference Between CURRENT_TIMESTAMP and GETDATE ()?” Very simple question but have showed up so frequently that I feel like to write about it. Well in SQL Server GETDATE() is Equivalent to CURRENT_TIMESTAMP. However, if you use CURRENT_TIMESTAMP in your select statement it will work fine. You can see in the above example – both of them returns the same value. Now let us go to next question regarding difference between GETDATE and CURRENT_TIMESTAMP. Well, the matter of the fact, there is no difference between them in SQL Server (Reference Link). CURRENT_TIMESTAMP is an ANSI SQL function, whereas GETDATE is T-SQL implementation of the same function. Both of them derive value from the operating system of the computer on which SQL Server instance is running. Above discussion prompts another question – in this case, what should one use GETDATE or CURRENT_TIMESTAMP? Well, this is indeed tricky and interesting question. I think I am very comfortable using the GETDATE () so I will go to use it but a matter of the fact there is no right or wrong answer. If you want to follow ancient saying “When in Rome, do as the Romans do”, I suggest using the GETDATE (), or continue using CURRENT_TIMESTAMP. With that said, there is one very important property we all need to keep in mind. If you use CURRENT_TIMESTAMP while creating an object, they are automatically converted to GETDATE() and stored internally. To illustrate what I am suggesting here is the example - Create a table using the following script CREATE TABLE [dbo].[TestTable]( [Cold2] [datetime] NULL ) ON [PRIMARY] GO ALTER TABLE [dbo].[TestTable] ADD DEFAULT (CURRENT_TIMESTAMP) FOR [Cold2] GO Now go to SSMS and generate the script for the table and you will notice following syntax. CREATE TABLE [dbo].[TestTable]( [Cold2] [datetime] NULL ) ON [PRIMARY] GO ALTER TABLE [dbo].[TestTable] ADD DEFAULT (GETDATE()) FOR [Cold2] GO You can notice that SQL Server have automatically converted CURRENT_TIMESTAMP to GETDATE(). I guess this gives us an idea how they behave. Now go ahead and make your choice! Do let me know which one will you use CURRENT_TIMESTAMP or GETDATE () in the comments area. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL DateTime, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

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• Get Unity to read in objects name without the need to hard code

  - by N0xus

  I'm trying to get away from having to hard code in the names of objects I want my code to use. For example, I'm use to do it this way: TextAsset test = new TextAsset(); test = (TextAsset)Resources.Load("test.txt", typeof(TextAsset)); What I want to know, is there a way to have so that when I drag my test.txt file onto my object in Unity, my code automatically gets the name of that object? I'm wanting to do this so once I write the code, I don't need to back in and change it should I wish re-use it.

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• APress Deal of the Day 16/August/2014 - Node.js Recipes

  - by TATWORTH

  Originally posted on: http://geekswithblogs.net/TATWORTH/archive/2014/08/15/apress-deal-of-the-day-16august2014---node.js-recipes.aspxToday’s $10 Deal of the Day from APress at http://www.apress.com/9781430260585 is Node.js Recipes. “Node.js Recipes is your one-stop reference for solving Node.js problems. Filled with useful recipes that follow a problem/solution format, you can look up recipes for many situations that you may come across in your day-to-day server-side development. ”

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• Be Careful When Referencing SPList.Items

  - by Brian Jackett

  Be very careful how you reference your SPListItem objects through the SharePoint API.  I’ll say it again.  Be very careful how you reference your SPListItem objects through the SharePoint API.  Ok, now that you get the point that this will be a “learn from my mistakes and don’t do unsmart things like I did” post, let’s dig into what it was that I did poorly. Scenario     For the past year I’ve been building custom .Net applications that are hosted through SharePoint.  These application involve a number of SharePoint lists, external databases, custom web parts, and other SharePoint elements to provide functionality.  About two weeks ago I received a message from one of our end users that a custom application was performing slowly.  Specifically performance was slow when users were performing actions that interacted with the primary SharePoint list storing data for that app. The Problem     I took a copy of the production site into a dev environment to investigate the code that was executing.  After attaching the debugger and running through the code I quickly found pieces of code referencing SPListItem objects (like below) that were performing very poorly: SPListItem myItem = SPContext.Current.Web.Lists["List Name"].Items.GetItemById(value); // do updates on SPListItem retrieved     As it turns out the SPList I was referencing was fairly large at ~1000 items and weighing in over 150 MB.  You see the problem with my above code is that I retrieved the SPListItem by first (unnecessarily) going through the Items member of the list.  As I understand it, when doing so the executing code will attempt to resolve that entity and pull it from the database and into RAM (all 150 MB.)  This causes the equivalent of a 50 car pile up in terms of performance with a single update taking more than 15 seconds. The Solution     The solution is actually quite simple and I wish I had realized this during development.  Instead of going through the Items member it is possible to call GetItemById(…) directly on the SPList as in the example below: SPListItem myItem = SPContext.Current.Web.Lists["List Name"].GetItemById(value); // do updates on SPListItem retrieved     After making this simple change performance skyrocketed and updates were back to less than a second.   Conclusion     When given the option between two solutions, usually the simplest is the best solution.  In my scenario I was adding extra complexity going through the API the long way around to get to the objects I needed and it ended up hurting performance greatly.  Luckily we were able to find and resolve the performance issue in a relatively short amount of time.  Like I said at the beginning of the post, learn from my mistakes and hope it helps you.         -Frog Out   Image linked from http://www.freespirit.com/files/IMAGE/COVER/LARGE/BeCarefulSafe.jpg

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