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• Future Of F# At Jazoon 2011

  - by Alois Kraus

  I was at the Jazoon 2011 in Zurich (Switzerland). It was a really cool event and it had many top notch speaker not only from the Microsoft universe. One of the most interesting talks was from Don Syme with the title: F# Today/F# Tomorrow. He did show how to use F# scripting to browse through open databases/, OData Web Services, Sharepoint, …interactively. It looked really easy with the help of F# Type Providers which is the next big language feature in a future F# version. The object returned by a Type Provider is used to access the data like in usual strongly typed object model. No guessing how the property of an object is called. Intellisense will show it just as you expect. There exists a range of Type Providers for various data sources where the schema of the stored data can somehow be dynamically extracted. Lets use e.g. a free database it would be then let data = DbProvider(http://.....); data the object which contains all data from e.g. a chemical database. It has an elements collection which contains an element which has the properties: Name, AtomicMass, Picture, …. You can browse the object returned by the Type Provider with full Intellisense because the returned object is strongly typed which makes this happen. The same can be achieved of course with code generators that use an input the schema of the input data (OData Web Service, database, Sharepoint, JSON serialized data, …) and spit out the necessary strongly typed objects as an assembly. This does work but has the downside that if the schema of your data source is huge you will quickly run against a wall with traditional code generators since the generated “deserialization” assembly could easily become several hundred MB. *** The following part contains guessing how this exactly work by asking Don two questions **** Q: Can I use Type Providers within C#? D: No. Q: F# is after all a library. I can reference the F# assemblies and use the contained Type Providers? D: F# does annotate the generated types in a special way at runtime which is not a static type that C# could use. The F# type providers seem to use a hybrid approach. At compilation time the Type Provider is instantiated with the url of your input data. The obtained schema information is used by the compiler to generate static types as usual but only for a small subset (the top level classes up to certain nesting level would make sense to me). To make this work you need to access the actual data source at compile time which could be a problem if you want to keep the actual url in a config file. Ok so this explains why it does work at all. But in the demo we did see full intellisense support down to the deepest object level. It looks like if you navigate deeper into the object hierarchy the type provider is instantiated in the background and attach to a true static type the properties determined at run time while you were typing. So this type is not really static at all. It is static if you define as a static type that its properties shows up in intellisense. But since this type information is determined while you are typing and it is not used to generate a true static type and you cannot use these “intellistatic” types from C#. Nonetheless this is a very cool language feature. With the plotting libraries you can generate expressive charts from any datasource within seconds to get quickly an overview of any structured data storage. My favorite programming language C# will not get such features in the near future there is hope. If you restrict yourself to OData sources you can use LINQPad to query any OData enabled data source with LINQ with ease. There you can query Stackoverflow with The output is also nicely rendered which makes it a very good tool to explore OData sources today.

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• When does a Tumbling Window Start in StreamInsight

  Whilst getting some courseware ready I was playing around writing some code and I decided to very simply show when a window starts and ends based on you asking for a TumblingWindow of n time units in StreamInsight.  I thought this was going to be a two second thing but what I found was something I haven’t yet found documented anywhere until now.   All this code is written in C# and will slot straight into my favourite quick-win dev tool LinqPad   Let’s first create a sample dataset   var EnumerableCollection = new [] { new {id = 1, StartTime = DateTime.Parse("2010-10-01 12:00:00 PM").ToLocalTime()}, new {id = 2, StartTime = DateTime.Parse("2010-10-01 12:20:00 PM").ToLocalTime()}, new {id = 3, StartTime = DateTime.Parse("2010-10-01 12:30:00 PM").ToLocalTime()}, new {id = 4, StartTime = DateTime.Parse("2010-10-01 12:40:00 PM").ToLocalTime()}, new {id = 5, StartTime = DateTime.Parse("2010-10-01 12:50:00 PM").ToLocalTime()}, new {id = 6, StartTime = DateTime.Parse("2010-10-01 01:00:00 PM").ToLocalTime()}, new {id = 7, StartTime = DateTime.Parse("2010-10-01 01:10:00 PM").ToLocalTime()}, new {id = 8, StartTime = DateTime.Parse("2010-10-01 02:00:00 PM").ToLocalTime()}, new {id = 9, StartTime = DateTime.Parse("2010-10-01 03:20:00 PM").ToLocalTime()}, new {id = 10, StartTime = DateTime.Parse("2010-10-01 03:30:00 PM").ToLocalTime()}, new {id = 11, StartTime = DateTime.Parse("2010-10-01 04:40:00 PM").ToLocalTime()}, new {id = 12, StartTime = DateTime.Parse("2010-10-01 04:50:00 PM").ToLocalTime()}, new {id = 13, StartTime = DateTime.Parse("2010-10-01 05:00:00 PM").ToLocalTime()}, new {id = 14, StartTime = DateTime.Parse("2010-10-01 05:10:00 PM").ToLocalTime()} };   Now let’s create a stream of point events   var inputStream = EnumerableCollection .ToPointStream(Application,evt=> PointEvent .CreateInsert(evt.StartTime,evt),AdvanceTimeSettings.StrictlyIncreasingStartTime);   Now we can create our windows over the stream.  The first window we will create is a one hour tumbling window.  We’'ll count the events in the window but what we do here is not the point, the point is our window edges.   var windowedStream = from win in inputStream.TumblingWindow(TimeSpan.FromHours(1),HoppingWindowOutputPolicy.ClipToWindowEnd) select new {CountOfEntries = win.Count()};   Now we can have a look at what we get.  I am only going to show the first non Cti event as that is enough to demonstrate what is going on   windowedStream.ToIntervalEnumerable().First(e=> e.EventKind == EventKind.Insert).Dump("First Row from Windowed Stream");   The results are below   EventKind Insert   StartTime 01/10/2010 12:00   EndTime 01/10/2010 13:00     { CountOfEntries = 5 }   Payload CountOfEntries 5   Now this makes sense and is quite often the width of window specified in examples.  So what happens if I change the windowing code now to var windowedStream = from win in inputStream.TumblingWindow(TimeSpan.FromHours(5),HoppingWindowOutputPolicy.ClipToWindowEnd) select new {CountOfEntries = win.Count()}; Now where does your window start?  What about   var windowedStream = from win in inputStream.TumblingWindow(TimeSpan.FromMinutes(13),HoppingWindowOutputPolicy.ClipToWindowEnd) select new {CountOfEntries = win.Count()};   Well for the first example your window will start at 01/10/2010 10:00:00 , and for the second example it will start at  01/10/2010 11:55:00 Surprised?   Here is the reason why and thanks to the StreamInsight team for listening.   Windows start at TimeSpan.MinValue. Windows are then created from that point onwards of the size you specified in your code.  If a window contains no events they are not produced by the engine to the output.  This is why window start times can be before the first event is created.

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• .NET "must-have" development tools

  - by nzpcmad

  James Avery wrote a classic article a while back entitled Ten Must-Have Tools Every Developer Should Download Now which is a companion to Visual Studio Add-Ins Every Developer Should Download Now and Scott Hanselman has an excellent list on his blog but if you were on a desert island and were only allowed three .NET development tools which ones would you pick? Update: Assuming you already have an IDE like Visual Studio ... Update (5) : Up to 08/01 : The current state of play: Reflector 13 Resharper 9 NUnit + TestDriven.Net 7 Refactor Pro 4 Process Explorer (other Sysinternals) 3 SnippetCompiler 3 CodeRush 3 MSDN Library 2 LinqPad 2 Cruisecontrol.net 2 VMWare 2 RhinoMocks 2 Fiddler 2 PowerShell 2 PowerCommands for VS 2008 1 Sandcastle 1 SQL Profiler 1 Redgate ANTS profiler 11 NCover 1 VisualSVN 1 Rubber Ducky 1 WinMerge 1 NAnt 1 ViEmu 1 AnkhSVN 1 dotTrace Profiler 1 BeyondCompare 1 DPack VS Plugin 1 WCF Trace Viewer (SDK) 1 xUnit.net 1 SourceGear DiffMerge 1 Ghostdoc 1 Expression Studio 1 XAML Pad 1 KaXaml 1 Blender for 3D modeling 1 Snoop a WPF tool 1 DiffMerge 1 DPack 1 NDepend 1 Kodos 1 WatiN 1 HTTPWatch Basic Edition 1 Paint.Net 1 Mole For VS 1 What I find particularly interesting about this is that "NUnit + TestDriven.Net " is right up there in third place which shows the growing emphasis on testing as an integral part of the development process rather than as an adjunct which is simply bolted on. And I'm somewhat perplexed that Codesmith didn't receive a single vote?

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• vb6 ADODB connection string to sql server 2008

  - by phill

  I recently migrated a database from sql server 2005 to 2008 on windows server 2008. Clients connect fine from their XP machines and so does the SQL Management Studio 2008. I have also tested a remote connection using LINQPad which worked fine. However on my VB6 app, the connection string seems to give me problems. Any ideas what I'm doing wrong? Dim strUserName As String Dim strPassword As String Dim sProc As String sProc = "Class_clsAdoFnx_Initialize" Me.DatabaseName = "db_app" 'Connect to SQL Server strUserName = "admin" strPassword = "mudslinger" Set cSQLConn = New ADODB.Connection '**Original connection String 'cSQLConn.CommandTimeout = 0 'cSQLConn.ConnectionString = " PROVIDER=SQLOLEDB" & _ ' ";SERVER=NET-BRAIN" & _ ' ";UID=" & strUserName & _ ' ";PWD=" & strPassword & _ ' ";DATABASE=" & Me.DatabaseName '***First attempt, no dice 'cSQLConn.ConnectionString = "Provider=sqloledb;" & _ ' "Data Source=NET-BRAIN;" & _ ' "Initial Catalog=DB_APP;" & _ ' "User Id=admin;" & _ ' "Password=mudslinger" 'cSQLConn.Open '***3rd attempt, no dice cSQLConn.Open "Provider=sqloledb;" & _ "Data Source=NET-BRAIN;" & _ "Initial Catalog=db_app;" & _ "User Id=admin;" & _ "Password=mudslinger", "admin", "mudslinger" thanks in advance.

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• LEFT OUTER JOIN in Linq - How to Force

  - by dodegaard

  I have a LEFT OUTER OUTER join in LINQ that is combining with the outer join condition and not providing the desired results. It is basically limiting my LEFT side result with this combination. Here is the LINQ and resulting SQL. What I'd like is for "AND ([t2].[EligEnd] = @p0" in the LINQ query to not bew part of the join condition but rather a subquery to filter results BEFORE the join. Thanks in advance (samples pulled from LINQPad) - Doug (from l in Users join mr in (from mri in vwMETRemotes where met.EligEnd == Convert.ToDateTime("2009-10-31") select mri) on l.Mahcpid equals mr.Mahcpid into lo from g in lo.DefaultIfEmpty() orderby l.LastName, l.FirstName where l.LastName.StartsWith("smith") && l.DeletedDate == null select g) Here is the resulting SQL -- Region Parameters DECLARE @p0 DateTime = '2009-10-31 00:00:00.000' DECLARE @p1 NVarChar(6) = 'smith%' -- EndRegion SELECT [t2].[test], [t2].[MAHCPID] AS [Mahcpid], [t2].[FirstName], [t2].[LastName], [t2].[Gender], [t2].[Address1], [t2].[Address2], [t2].[City], [t2].[State] AS [State], [t2].[ZipCode], [t2].[Email], [t2].[EligStart], [t2].[EligEnd], [t2].[Dependent], [t2].[DateOfBirth], [t2].[ID], [t2].[MiddleInit], [t2].[Age], [t2].[SSN] AS [Ssn], [t2].[County], [t2].[HomePhone], [t2].[EmpGroupID], [t2].[PopulationIdentifier] FROM [dbo].[User] AS [t0] LEFT OUTER JOIN ( SELECT 1 AS [test], [t1].[MAHCPID], [t1].[FirstName], [t1].[LastName], [t1].[Gender], [t1].[Address1], [t1].[Address2], [t1].[City], [t1].[State], [t1].[ZipCode], [t1].[Email], [t1].[EligStart], [t1].[EligEnd], [t1].[Dependent], [t1].[DateOfBirth], [t1].[ID], [t1].[MiddleInit], [t1].[Age], [t1].[SSN], [t1].[County], [t1].[HomePhone], [t1].[EmpGroupID], [t1].[PopulationIdentifier] FROM [dbo].[vwMETRemote] AS [t1] ) AS [t2] ON ([t0].[MAHCPID] = [t2].[MAHCPID]) AND ([t2].[EligEnd] = @p0) WHERE ([t0].[LastName] LIKE @p1) AND ([t0].[DeletedDate] IS NULL) ORDER BY [t0].[LastName], [t0].[FirstName]

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• Using Lambda Expressions trees with IEnumerable

  - by Loathian

  I've been trying to learn more about using Lamba expression trees and so I created a simple example. Here is the code, this works in LINQPad if pasted in as a C# program. void Main() { IEnumerable<User> list = GetUsers().Where(NameContains("a")); list.Dump("Users"); } // Methods public IEnumerable<User> GetUsers() { yield return new User{Name = "andrew"}; yield return new User{Name = "rob"}; yield return new User{Name = "chris"}; yield return new User{Name = "ryan"}; } public Expression<Func<User, bool>> NameContains(string namePart) { return u => u.Name.Contains(namePart); } // Classes public class User { public string Name { get; set; } } This results in the following error: The type arguments for method 'System.Linq.Enumerable.Where(System.Collections.Generic.IEnumerable, System.Func)' cannot be inferred from the usage. Try specifying the type arguments explicitly. However if I just substitute the first line in main with this: IEnumerable<User> list = GetUsers().Where(u => u.Name.Contains("a")); It works fine. Can tell me what I'm doing wrong, please?

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• Is it OK to use WPF assemblies in a web app?

  - by Chris

  I have an ASP.NET MVC 2 app targeting .NET 4 that needs to be able to resize images on the fly and write them to the response. I have code that does this and it works. I am using System.Drawing.dll. However, I want to enhance my code so that not only am I resizing the image, but I am dropping it from 24bpp down to 4bit grayscale. I could not, for the life of me, find code on how to do this with System.Drawing.dll. But I did find a bunch of WPF stuff. This is my working/sample code (runs in LinqPad). // Load the original 24 bit image var bitmapImage = new BitmapImage(); bitmapImage.BeginInit(); bitmapImage.UriSource = new Uri(@"C:\Temp\Resized\18_appa2_015.png", UriKind.Absolute); //bitmapImage.DecodePixelWidth = 600; bitmapImage.EndInit(); // Create the destination image var formatConvertedBitmap = new FormatConvertedBitmap(); formatConvertedBitmap.BeginInit(); formatConvertedBitmap.Source = bitmapImage; formatConvertedBitmap.DestinationFormat = PixelFormats.Gray4; formatConvertedBitmap.EndInit(); // Encode and dump the image to disk var encoder = new PngBitmapEncoder(); encoder.Frames.Add(BitmapFrame.Create(formatConvertedBitmap)); using (var fileStream = File.Create(@"C:\Temp\Resized\18_appa2_015_s2.png")) { encoder.Save(fileStream); } It uses System.Xaml.dll, WindowsBase.dll, PresentationCore.dll, and PresentationFramework.dll. The namespaces used are: System.Windows.Controls, System.Windows.Media, and System.Windows.Media.Imaging. Is there any problem using these namespaces in my web application? It doesn't seem right. If anyone knows how to drop the bit depth without all this WPF stuff (which I barely understand, BTW) I would be thrilled to see that too.

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• Entity Framework not populating context

  - by stimms

  I'm just starting out with some entity framework exploration, I figured it was time to see what everybody was complaining about. I am running into an issue where the entities don't seem to be returning any of the object context. I generated the model from a database with three tables which link to one another. Courses Instructors CanTeach Relationships are as you would expect: a course can relate to multiple CanTeach entities and an instructor can also relate to multiple CanTeach entities. I also added an OData service to my project which also makes use of the same model. So I can run queries like from a in CanTeach where a.Instructor.FirstName == "Barry" select new { Name = a.Instructor.FirstName + " " + a.Instructor.LastName, Course = a.Course.Name} without issue against the OData endpoint using LINQPad. However when I do a simple query like public Instructor GetInstructorFromID(int ID) { return context.Instructors.Where(i => i.ID == ID).FirstOrDefault(); } The CanTeach list is empty. I know everything in EF is lazy loaded and it is possible that my context is out of scope by the time I look at the object context, however even trying to get the object context as soon as the query is run results in and empty object context. What am I doing wrong?

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• Why are my bound parameters all identical (using Linq)?

  - by Scott Stafford

  When I run this snippet of code: string[] words = new string[] { "foo", "bar" }; var results = from row in Assets select row; foreach (string word in words) { results = results.Where(row => row.Name.Contains(word)); } I get this SQL: -- Region Parameters DECLARE @p0 VarChar(5) = '%bar%' DECLARE @p1 VarChar(5) = '%bar%' -- EndRegion SELECT ... FROM [Assets] AS [t0] WHERE ([t0].[Name] LIKE @p0) AND ([t0].[Name] LIKE @p1) Note that @p0 and @p1 are both bar, when I wanted them to be foo and bar. I guess Linq is somehow binding a reference to the variable word rather than a reference to the string currently referenced by word? What is the best way to avoid this problem? (Also, if you have any suggestions for a better title for this question, please put it in the comments.) Note that I tried this with regular Linq also, with the same results (you can paste this right into Linqpad): string[] words = new string[] { "f", "a" }; string[] dictionary = new string[] { "foo", "bar", "jack", "splat" }; var results = from row in dictionary select row; foreach (string word in words) { results = results.Where(row => row.Contains(word)); } results.Dump(); Dumps: bar jack splat

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• LINQ to SQL Converter

  - by user609511

  How can I convert My LINQ to SQL ? i have this LINQ statement: int LimCol = Convert.ToInt32(LimitColis); result = oListTUP .GroupBy(x => new { x.Item1, x.Item2, x.Item3, x.Item4, x.Item5 }) .Select(g => new { Key = g.Key, Sum = g.Sum(x => x.Item6), Poids = g.Sum(x => x.Item7), }) .Select(p => new { Key = p.Key, Items = Enumerable.Repeat(LimCol, p.Sum / LimCol).Concat(Enumerable.Repeat(p.Sum % LimCol, p.Sum % LimCol > 0 ? 1 : 0)), CalculPoids = p.Poids / Enumerable.Repeat(LimCol, p.Sum / LimCol).Concat(Enumerable.Repeat(p.Sum % LimCol, p.Sum % LimCol > 0 ? 1 : 0)).Count() }) .SelectMany(p => p.Items.Select(i => Tuple.Create(p.Key.Item1, p.Key.Item2, p.Key.Item3, p.Key.Item4, p.Key.Item5, i, p.CalculPoids))) .ToList(); } It works well, but somehow want to push it and it become too complicated, so I want to convert it into Pure SQL. I have tried SQL Profiler and LinqPad, but neither shows me the SQL. How can I see the SQL code from My LINQ ? Thank you in advance.

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• I want to virtualize my workstation (Tier 1), Looking for Bare Metal Hypervisor for consumer grade components

  - by Chase Florell

  I find myself in this similar bind at least once a year. The bind whereby I'm either upgrading a motherboard, or an OS hard drive. It drives me crazy to have to reinstall Windows, Visual Studio, all my addins, reconfigure my settings etc... every single time. I have a layout and I like and I want to stick with it. My question is... Is there a Bare Metal Hypervisor on the market that will enable me to virtualize my consumer grade workstation? I really want to avoid Host/Client virtualization. Bare Metal is definitely a better way to go for my needs. Is this a good approach, or am I going to suffer some other undesirable side effects by doing this? Clarification My machine has very limited purposes. My primary use is Visual Studio 2010 Professional where I develop ASP.NET MVC Web Applications. The second piece of software that I use (that's system intensive) is Photoshop CS3. Beyond that, my applications are limited to Outlook, Internet Explorer, Firefox, Opera, Chrome, LinqPad, and various other (small) apps. Beyond this, I'm considering working on a node.js project and might run ubuntu on the same hypervisor if possible. System Specs: Gigabyte Motherboard Intel i7 920 12 GB Ram basic 500GB 7200RPM HDD for OS 4 VelociRaptors in Raid 1/0 for build disk Dual GTS250 (512MB) Graphics cards (non SLI) for quad monitors On a side note I also wouldn't be opposed to an alternative suggestion if the limitations are too great. I could install the ESXi (or Zen Server) on my box, and build a separate "thin client" to RDP into the virtual machine. It appears as though RDP supports dual monitors. Edit (Dec 9, 2011) It's been nearly a year since I first asked this question. Since then, there have been a lot of great strides in Hypervisor technology... AND MokaFive is now released for corporate use. I'd love to dig into this question a little more and find out if there is a solid BareMetal Hypervisor for workstations running consumer grade components (IE: not Dell, HP, Lenovo, Etc).

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• LINQ to XML Cloning

  - by Sir Psycho

  Can anyone explain why the original address XElement street node changes? It looks like customer1 holds a reference to the address XElement but customer2 and customer3 have taken copies. Why did the original address change? (LINQPad example) var address = new XElement ("address", new XElement ("street", "Lawley St"), new XElement ("town", "North Beach") ); var customer1 = new XElement ("customer1", address); var customer2 = new XElement ("customer2", address); var customer3 = new XElement ("customer3", address); customer1.Element ("address").Element ("street").Value = "Another St"; Console.WriteLine (customer2.Element ("address").Element ("street").Value); Console.WriteLine (); address.Dump(); Console.WriteLine (); customer1.Dump(); Console.WriteLine (); customer2.Dump(); Console.WriteLine (); customer3.Dump(); OUTPUT Lawley St <address> <street>Another St</street> <town>North Beach</town> </address> <customer1> <address> <street>Another St</street> <town>North Beach</town> </address> </customer1> <customer2> <address> <street>Lawley St</street> <town>North Beach</town> </address> </customer2> <customer3> <address> <street>Lawley St</street> <town>North Beach</town> </address> </customer3>

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• How to write this Linq SQL as a Dynamic Query (using strings)?

  - by Dr. Zim

  Skip to the "specific question" as needed. Some background: The scenario: I have a set of products with a "drill down" filter (Query Object) populated with DDLs. Each progressive DDL selection will further limit the product list as well as what options are left for the DDLs. For example, selecting a hammer out of tools limits the Product Sizes to only show hammer sizes. Current setup: I created a query object, sent it to a repository, and fed each option to a SQL "table valued function" where null values represent "get all products". I consider this a good effort, but far from DDD acceptable. I want to avoid any "programming" in SQL, hopefully doing everything with a repository. Comments on this topic would be appreciated. Specific question: How would I rewrite this query as a Dynamic Query? A link to something like 101 Linq Examples would be fantastic, but with a Dynamic Query scope. I really want to pass to this method the field in quotes "" for which I want a list of options and how many products have that option. from p in db.Products group p by p.ProductSize into g select new Category { PropertyType = g.Key, Count = g.Count() } Each DDL option will have "The selection (21)" where the (21) is the quantity of products that have that attribute. Upon selecting an option, all other remaining DDLs will update with the remaining options and counts. Edit: Additional notes: .OrderBy("it.City") // "it" refers to the entire record .GroupBy("City", "new(City)") // This produces a unique list of City .Select("it.Count()") //This gives a list of counts... getting closer .Select("key") // Selects a list of unique City .Select("new (key, count() as string)") // +1 to me LOL. key is a row of group .GroupBy("new (City, Manufacturer)", "City") // New = list of fields to group by .GroupBy("City", "new (Manufacturer, Size)") // Second parameter is a projection Product .Where("ProductType == @0", "Maps") .GroupBy("new(City)", "new ( null as string)")// Projection not available later? .Select("new (key.City, it.count() as string)")// GroupBy new makes key an object Product .Where("ProductType == @0", "Maps") .GroupBy("new(City)", "new ( null as string)")// Projection not available later? .Select("new (key.City, it as object)")// the it object is the result of GroupBy var a = Product .Where("ProductType == @0", "Maps") .GroupBy("@0", "it", "City") // This fails to group Product at all .Select("new ( Key, it as Product )"); // "it" is property cast though What I have learned so far is LinqPad is fantastic, but still looking for an answer. Eventually, completely random research like this will prevail I guess. LOL. Edit:

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• How are you using IronPython?

  - by Will Dean

  I'm keen to drink some modern dynamic language koolaid, so I've believed all the stuff on Michael Foord's blog and podcasts, I've bought his book (and read some of it), and I added an embedded IPy runtime to a large existing app a year or so ago (though that was for someone else and I didn't really use it myself). Now I need to do some fairly simple code generation stuff, where I'm going to call a few methods on a few .net objects (custom, C#-authored objects), create a few strings, write some files, etc. The experience of trying this leaves me feeling like the little boy who thinks he's the only one who can see that The Emperor has no clothes on. If you're using IronPython, I'd really appreciate knowing how you deal with the following aspects of it: Code editing - do you use the .NET framework without Intellisense? Refactoring - I know a load of 'refactoring' is about working around language-related busywork, so if Python is sufficiently lightweight then we won't need that, But things like renames seem to me to be essential to iteratively developing quality code regardless of language. Crippling startup time - One of the things which is supposed to be good about interpreted languages is the lack of compile time leading to fast interactive development. Unfortunately I can compile a C# application and launch it quicker than IPy can start up. Interactive hacking - the IPy console/repl is supposed to be good for this, but I haven't found a good way to take the code you've interactively arrived at and persist it into a file - cut and paste from the console is fairly miserable. And the console seems to hold references to .NET assemblies you've imported, so you have to quit it and restart it if you're working on the C# stuff as well. Hacking on C# in something like LinqPad seems a much faster and easier way to try things out (and has proper Intellisense). Do you use the console? Debugging - what's the story here? I know someone on the IPy team is working on a command-line hobby-project, but let's just say I'm not immediately attracted to a command line debugger. I don't really need a debugger from little Python scripts, but I would if I were to use IPy for scripting unit tests, for example. Unit testing - I can see that dynamic languages could be great for this, but is there any IDE test-runner integration (like for Resharper, etc). The Foord book has a chapter about this, which I'll admit I have not yet read properly, but it does seem to involve driving a console-mode test-runner from the command prompt, which feels to be an enormous step back from using an integrated test runner like TestDriven.net or Resharper. I really want to believe in this stuff, so I am still working on the assumption that I've missed something. I would really like to know how other people are dealing with IPy, particularly if they're doing it in a way which doesn't feel like we've just lost 15 years'-worth of tool development.

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• Generated LinqtoSql Sql 5x slower than SAME EXACT hand-written sql

  - by JasonM

  I have a sql statement which is hardcoded in an existing VB6 app. I'm upgrading a new version in C# and using Linq To Sql. I was able to get LinqToSql to generate the same sql (before I start refactoring), but for some reason the Sql generated by LinqToSql is 5x slower than the original sql. This is running the generated Sql Directly in LinqPad. The only real difference my meager sql eyes can spot is the WITH (NOLOCK), which if I add into the LinqToSql generated sql, makes no difference. Can someone point out what I'm doing wrong here? Thanks! Existing Hard Coded Sql (5.0 Seconds) SELECT DISTINCT CH.ClaimNum, CH.AcnProvID, CH.AcnPatID, CH.TinNum, CH.Diag1, CH.GroupNum, CH.AllowedTotal FROM Claims.dbo.T_ClaimsHeader AS CH WITH (NOLOCK) WHERE CH.ContractID IN ('123A','123B','123C','123D','123E','123F','123G','123H') AND ( ( (CH.Transmited Is Null or CH.Transmited = '') AND CH.DateTransmit Is Null AND CH.EobDate Is Null AND CH.ProcessFlag IN ('Y','E') AND CH.DataSource NOT IN ('A','EC','EU') AND CH.AllowedTotal > 0 ) ) ORDER BY CH.AcnPatID, CH.ClaimNum Generated Sql from LinqToSql (27.6 Seconds) -- Region Parameters DECLARE @p0 NVarChar(4) SET @p0 = '123A' DECLARE @p1 NVarChar(4) SET @p1 = '123B' DECLARE @p2 NVarChar(4) SET @p2 = '123C' DECLARE @p3 NVarChar(4) SET @p3 = '123D' DECLARE @p4 NVarChar(4) SET @p4 = '123E' DECLARE @p5 NVarChar(4) SET @p5 = '123F' DECLARE @p6 NVarChar(4) SET @p6 = '123G' DECLARE @p7 NVarChar(4) SET @p7 = '123H' DECLARE @p8 VarChar(1) SET @p8 = '' DECLARE @p9 NVarChar(1) SET @p9 = 'Y' DECLARE @p10 NVarChar(1) SET @p10 = 'E' DECLARE @p11 NVarChar(1) SET @p11 = 'A' DECLARE @p12 NVarChar(2) SET @p12 = 'EC' DECLARE @p13 NVarChar(2) SET @p13 = 'EU' DECLARE @p14 Decimal(5,4) SET @p14 = 0 -- EndRegion SELECT DISTINCT [t0].[ClaimNum], [t0].[acnprovid] AS [AcnProvID], [t0].[acnpatid] AS [AcnPatID], [t0].[tinnum] AS [TinNum], [t0].[diag1] AS [Diag1], [t0].[GroupNum], [t0].[allowedtotal] AS [AllowedTotal] FROM [Claims].[dbo].[T_ClaimsHeader] AS [t0] WHERE ([t0].[contractid] IN (@p0, @p1, @p2, @p3, @p4, @p5, @p6, @p7)) AND (([t0].[Transmited] IS NULL) OR ([t0].[Transmited] = @p8)) AND ([t0].[DATETRANSMIT] IS NULL) AND ([t0].[EOBDATE] IS NULL) AND ([t0].[PROCESSFLAG] IN (@p9, @p10)) AND (NOT ([t0].[DataSource] IN (@p11, @p12, @p13))) AND ([t0].[allowedtotal] > @p14) ORDER BY [t0].[acnpatid], [t0].[ClaimNum] New LinqToSql Code (30+ seconds... Times out ) var contractIds = T_ContractDatas.Where(x => x.EdiSubmissionGroupID == "123-01").Select(x => x.CONTRACTID).ToList(); var processFlags = new List<string> {"Y","E"}; var dataSource = new List<string> {"A","EC","EU"}; var results = (from claims in T_ClaimsHeaders where contractIds.Contains(claims.contractid) && (claims.Transmited == null || claims.Transmited == string.Empty ) && claims.DATETRANSMIT == null && claims.EOBDATE == null && processFlags.Contains(claims.PROCESSFLAG) && !dataSource.Contains(claims.DataSource) && claims.allowedtotal > 0 select new { ClaimNum = claims.ClaimNum, AcnProvID = claims.acnprovid, AcnPatID = claims.acnpatid, TinNum = claims.tinnum, Diag1 = claims.diag1, GroupNum = claims.GroupNum, AllowedTotal = claims.allowedtotal }).OrderBy(x => x.ClaimNum).OrderBy(x => x.AcnPatID).Distinct(); I'm using the list of constants above to make LinqToSql Generate IN ('xxx','xxx',etc) Otherwise it uses subqueries which are just as slow...

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• Entity Framework v1 &ndash; tips and Tricks Part 3

  - by Rohit Gupta

  General Tips on Entity Framework v1 & Linq to Entities: ToTraceString() If you need to know the underlying SQL that the EF generates for a Linq To Entities query, then use the ToTraceString() method of the ObjectQuery class. (or use LINQPAD) Note that you need to cast the LINQToEntities query to ObjectQuery before calling TotraceString() as follows: 1: string efSQL = ((ObjectQuery)from c in ctx.Contact 2: where c.Address.Any(a => a.CountryRegion == "US") 3: select c.ContactID).ToTraceString(); ================================================================================ MARS or MultipleActiveResultSet When you create a EDM Model (EDMX file) from the database using Visual Studio, it generates a connection string with the same name as the name of the EntityContainer in CSDL. In the ConnectionString so generated it sets the MultipleActiveResultSet attribute to true by default. So if you are running the following query then it streams multiple readers over the same connection: 1: using (BAEntities context = new BAEntities()) 2: { 3: var cons = 4: from con in context.Contacts 5: where con.FirstName == "Jose" 6: select con; 7: foreach (var c in cons) 8: { 9: if (c.AddDate < new System.DateTime(2007, 1, 1)) 10: { 11: c.Addresses.Load(); 12: } 13: } 14: } ================================================================================= Explicitly opening and closing EntityConnection When you call ToList() or foreach on a LINQToEntities query the EF automatically closes the connection after all the records from the query have been consumed. Thus if you need to run many LINQToEntities queries over the same connection then explicitly open and close the connection as follows: 1: using (BAEntities context = new BAEntities()) 2: { 3: context.Connection.Open(); 4: var cons = from con in context.Contacts where con.FirstName == "Jose" 5: select con; 6: var conList = cons.ToList(); 7: var allCustomers = from con in context.Contacts.OfType<Customer>() 8: select con; 9: var allcustList = allCustomers.ToList(); 10: context.Connection.Close(); 11: } ====================================================================== Dispose ObjectContext only if required After you retrieve entities using the ObjectContext and you are not explicitly disposing the ObjectContext then insure that your code does consume all the records from the LinqToEntities query by calling .ToList() or foreach statement, otherwise the the database connection will remain open and will be closed by the garbage collector when it gets to dispose the ObjectContext. Secondly if you are making updates to the entities retrieved using LinqToEntities then insure that you dont inadverdently dispose of the ObjectContext after the entities are retrieved and before calling .SaveChanges() since you need the SAME ObjectContext to keep track of changes made to the Entities (by using ObjectStateEntry objects). So if you do need to explicitly dispose of the ObjectContext do so only after calling SaveChanges() and only if you dont need to change track the entities retrieved any further. ======================================================================= SQL InjectionAttacks under control with EFv1 LinqToEntities and LinqToSQL queries are parameterized before they are sent to the DB hence they are not vulnerable to SQL Injection attacks. EntitySQL may be slightly vulnerable to attacks since it does not use parameterized queries. However since the EntitySQL demands that the query be valid Entity SQL syntax and valid native SQL syntax at the same time. So the only way one can do a SQLInjection Attack is by knowing the SSDL of the EDM Model and be able to write the correct EntitySQL (note one cannot append regular SQL since then the query wont be a valid EntitySQL syntax) and append it to a parameter. ====================================================================== Improving Performance You can convert the EntitySets and AssociationSets in a EDM Model into precompiled Views using the edmgen utility. for e.g. the Customer Entity can be converted into a precompiled view using edmgen and all LinqToEntities query against the contaxt.Customer EntitySet will use the precompiled View instead of the EntitySet itself (the same being true for relationships (EntityReference & EntityCollections of a Entity)). The advantage being that when using precompiled views the performance will be much better. The syntax for generating precompiled views for a existing EF project is : edmgen /mode:ViewGeneration /inssdl:BAModel.ssdl /incsdl:BAModel.csdl /inmsl:BAModel.msl /p:Chap14.csproj Note that this will only generate precompiled views for EntitySets and Associations and not for existing LinqToEntities queries in the project.(for that use CompiledQuery.Compile<>) Secondly if you have a LinqToEntities query that you need to run multiple times, then one should precompile the query using CompiledQuery.Compile method. The CompiledQuery.Compile<> method accepts a lamda expression as a parameter, which denotes the LinqToEntities query  that you need to precompile. The following is a example of a lamda that we can pass into the CompiledQuery.Compile() method 1: Expression<Func<BAEntities, string, IQueryable<Customer>>> expr = (BAEntities ctx1, string loc) => 2: from c in ctx1.Contacts.OfType<Customer>() 3: where c.Reservations.Any(r => r.Trip.Destination.DestinationName == loc) 4: select c; Then we call the Compile Query as follows: 1: var query = CompiledQuery.Compile<BAEntities, string, IQueryable<Customer>>(expr); 2:  3: using (BAEntities ctx = new BAEntities()) 4: { 5: var loc = "Malta"; 6: IQueryable<Customer> custs = query.Invoke(ctx, loc); 7: var custlist = custs.ToList(); 8: foreach (var item in custlist) 9: { 10: Console.WriteLine(item.FullName); 11: } 12: } Note that if you created a ObjectQuery or a Enitity SQL query instead of the LINQToEntities query, you dont need precompilation for e.g. 1: An Example of EntitySQL query : 2: string esql = "SELECT VALUE c from Contacts AS c where c is of(BAGA.Customer) and c.LastName = 'Gupta'"; 3: ObjectQuery<Customer> custs = CreateQuery<Customer>(esql); 1: An Example of ObjectQuery built using ObjectBuilder methods: 2: from c in Contacts.OfType<Customer>().Where("it.LastName == 'Gupta'") 3: select c This is since the Query plan is cached and thus the performance improves a bit, however since the ObjectQuery or EntitySQL query still needs to materialize the results into Entities hence it will take the same amount of performance hit as with LinqToEntities. However note that not ALL EntitySQL based or QueryBuilder based ObjectQuery plans are cached. So if you are in doubt always create a LinqToEntities compiled query and use that instead ============================================================ GetObjectStateEntry Versus GetObjectByKey We can get to the Entity being referenced by the ObjectStateEntry via its Entity property and there are helper methods in the ObjectStateManager (osm.TryGetObjectStateEntry) to get the ObjectStateEntry for a entity (for which we know the EntityKey). Similarly The ObjectContext has helper methods to get an Entity i.e. TryGetObjectByKey(). TryGetObjectByKey() uses GetObjectStateEntry method under the covers to find the object, however One important difference between these 2 methods is that TryGetObjectByKey queries the database if it is unable to find the object in the context, whereas TryGetObjectStateEntry only looks in the context for existing entries. It will not make a trip to the database ============================================================= POCO objects with EFv1: To create POCO objects that can be used with EFv1. We need to implement 3 key interfaces: IEntityWithKey IEntityWithRelationships IEntityWithChangeTracker Implementing IEntityWithKey is not mandatory, but if you dont then we need to explicitly provide values for the EntityKey for various functions (for e.g. the functions needed to implement IEntityWithChangeTracker and IEntityWithRelationships). Implementation of IEntityWithKey involves exposing a property named EntityKey which returns a EntityKey object. Implementation of IEntityWithChangeTracker involves implementing a method named SetChangeTracker since there can be multiple changetrackers (Object Contexts) existing in memory at the same time. 1: public void SetChangeTracker(IEntityChangeTracker changeTracker) 2: { 3: _changeTracker = changeTracker; 4: } Additionally each property in the POCO object needs to notify the changetracker (objContext) that it is updating itself by calling the EntityMemberChanged and EntityMemberChanging methods on the changeTracker. for e.g.: 1: public EntityKey EntityKey 2: { 3: get { return _entityKey; } 4: set 5: { 6: if (_changeTracker != null) 7: { 8: _changeTracker.EntityMemberChanging("EntityKey"); 9: _entityKey = value; 10: _changeTracker.EntityMemberChanged("EntityKey"); 11: } 12: else 13: _entityKey = value; 14: } 15: } 16: ===================== Custom Property ==================================== 17:  18: [EdmScalarPropertyAttribute(IsNullable = false)] 19: public System.DateTime OrderDate 20: { 21: get { return _orderDate; } 22: set 23: { 24: if (_changeTracker != null) 25: { 26: _changeTracker.EntityMemberChanging("OrderDate"); 27: _orderDate = value; 28: _changeTracker.EntityMemberChanged("OrderDate"); 29: } 30: else 31: _orderDate = value; 32: } 33: } Finally you also need to create the EntityState property as follows: 1: public EntityState EntityState 2: { 3: get { return _changeTracker.EntityState; } 4: } The IEntityWithRelationships involves creating a property that returns RelationshipManager object: 1: public RelationshipManager RelationshipManager 2: { 3: get 4: { 5: if (_relManager == null) 6: _relManager = RelationshipManager.Create(this); 7: return _relManager; 8: } 9: } ============================================================ Tip : ProviderManifestToken – change EDMX File to use SQL 2008 instead of SQL 2005 To use with SQL Server 2008, edit the EDMX file (the raw XML) changing the ProviderManifestToken in the SSDL attributes from "2005" to "2008" ============================================================= With EFv1 we cannot use Structs to replace a anonymous Type while doing projections in a LINQ to Entities query. While the same is supported with LINQToSQL, it is not with LinqToEntities. For e.g. the following is not supported with LinqToEntities since only parameterless constructors and initializers are supported in LINQ to Entities. (the same works with LINQToSQL) 1: public struct CompanyInfo 2: { 3: public int ID { get; set; } 4: public string Name { get; set; } 5: } 6: var companies = (from c in dc.Companies 7: where c.CompanyIcon == null 8: select new CompanyInfo { Name = c.CompanyName, ID = c.CompanyId }).ToList(); ;

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• Tools of the Trade

  - by Ajarn Mark Caldwell

  I got pretty excited a couple of days ago when my new laptop arrived. “The new phone books are here!  The new phone books are here!  I’m a somebody!” - Steve Martin in The Jerk It is a Dell Precision M4500 with an Intel i7 Core 2.8 GHZ running 64-bit Windows 7 with a 15.6” widescreen, 8 GB RAM, 256 GB SSD.  For some of you high fliers, this may be nothing to write home about, but compared to the 32–bit Windows XP laptop with 2 GB of RAM and a regular hard disk that I’m coming from, it’s a really nice step forward.  I won’t even bore you with the details of the desktop PC I was first given when I started here 5 1/2 years ago.  Let’s just say that things have improved.  One really nice thing is that while we are definitely running a lean and mean department in terms of staffing, my boss believes in supporting that lean staff with good tools in order to stay lean instead of having to spend even more money on additional employees.  Of course, that only goes so far, and at some point you have to add more people in order to get more work done, which is why we are bringing on-board a new employee and a new contract developer next week.  But that’s a different story for a different time. But the main topic for this post is to highlight the variety of tools that I use in my job and that you might find useful, too.  This is easy to do right now because the process of building up my new laptop from scratch has forced me to assemble a list of software that had to be installed and configured.  Keep in mind as you look through this list that I play many roles in our company.  My official title is Software Engineering Manager, but in addition to managing the team, I am also an active ASP.NET and SQL developer, the Database Administrator, and 50% of the SAN Administrator team.  So, without further ado, here are the tools and some comments about why I use them: Tool Purpose Virtual Clone Drive Easily mount an ISO image as a DVD Drive.  This is particularly handy when you are downloading disk images from Microsoft for your tools. SQL Server 2008 R2 Developer Edition We are migrating all of our active systems to SQL 2008 R2.  Developer Edition has all the features of Enterprise Edition, but intended for development use. SQL Server 2005 Developer Edition (BIDS ONLY) The migration to SSRS 2008 R2 is just getting started, and in the meantime, maintenance work still has to be done on the reports on our SQL 2005 server.  For some reason, you can’t use BIDS from 2008 to write reports for a 2005 server.  There is some different format and when you open 2005 reports in 2008 BIDS, it forces you to upgrade, and they can no longer be uploaded to a 2005 server.  Hopefully Microsoft will fix this soon in some manner similar to Visual Studio now allows you to pick which version of the .NET Framework you are coding against. Visual Studio 2010 Premium All of our application development is in ASP.NET, and we might as well use the tool designed for it. I’ve used a version of Visual Studio going all the way back to VB 6.0 and Visual Interdev. Vault Professional Client Several years ago we replaced Visual Source Safe with SourceGear Vault (then Fortress, and now Vault Pro), and I love it.  It is very reliable with low overhead - perfect for a small to medium size development team.  And being a small ISV, their support is exceptional. Red-Gate Developer Bundle with the SQL Source Control update for Vault I first used, and fell in love with, SQL Prompt shortly before Red-Gate bought it, and then Red-Gate’s first release made me love it even more.  SQL Refactor (which has since been rolled into the latest version of SQL Prompt) has saved me many hours and migraine’s trying to understand somebody else’s code when their indenting was nonexistant, or worse, irrational.  SQL Compare has been awesome for troubleshooting potential schema issues between different instances of system databases.  SQL Data Compare helped us identify the cause behind a bug which appeared in PROD but could not be reproduced in a nearly (but not quite exactly) identical copy in UAT.  And the newest tool we are embracing: SQL Source Control.  I blogged about it here (and here, and here) last December.  This is really going to help us keep each developer’s copy of the database in sync with one another. Fiddler Helps you watch the whole traffic stream on web visits.  Haven’t used it a lot, but it did help me track down some odd 404 errors we were finding in our own application logs.  Has some other JavaScript troubleshooting capabilities, but some of its usefulness has been supplanted by the Developer Tools option in IE8. Funduc Search & Replace Find any string anywhere in a mound of source code really, really fast.  Does RegEx searches, if you understand that foreign language.  Has really helped with some refactoring work to pinpoint, for example, everywhere a particular stored procedure is referenced, whether in .NET code or other SQL procedures (which we have in script files).  Provides in-context preview of the search results.  Fantastic tool, and a bargain price. SciTE SciTE is a Scintilla based Text Editor and it is a fantastic, light-weight tool for quickly reviewing (or writing) program code, SQL scripts, and extract files.  It has language-specific syntax highlighting.  I used it to write several batch and CMD programs a year ago, and to examine data extract files for exchanging information with other systems.  Extremely handy are the options to View End of Line and View Whitespace.  Ever receive a file that is supposed to use CRLF as an end-of-line marker, but really only has CRs?  SciTE will quickly make that visible. Infragistics Controls We do a lot of ASP.NET development, and frequently use the WebGrid, WebTab, and date picker controls.  We will likely be implementing the Hierarchical Data Grid soon.  Infragistics has control suites for WebForms, WinForms, Silverlight, and coming soon MVC/JQuery. WinZip - WITH Command-Line add-in The classic compression program with a great command-line interface that allows me to build those CMD (and soon PowerShell) programs for automated compression jobs.  Our versioned Build packages are zip files. XML Notepad Haven’t used this a lot myself, but one of my team really likes it for examining large XML files. LINQPad Again, haven’t used this one a lot, but it was recommended to me for learning and practicing my LINQ skills which will come in handy as we implement Entity Framework. SQL Sentry Plan Explorer SQL Server Show Plan on steroids.  Great for helping you focus on the parts of a large query that are of most importance.  Also great for just compressing the graphical plan into more readable layout. Araxis Merge A great DIFF and Merge tool.  SourceGear provides a great tool called DiffMerge that we use all the time, but occasionally, I like the cross-edit capabilities of Araxis Merge.  For a while, we also produced DIFF reports in HTML that showed all the changes that occurred between two releases.  This was most important when we were putting out very small, but very important hot fixes on a very politically hot system.  The reports produced by Araxis Merge gave the Director of IS assurance that we were not accidentally introducing ripples throughout the system with our releases. Idera SQL Admin Toolset A great collection of tools including a password checker to help analyze your SQL Server for weak user passwords, a Backup Status tool to quickly scan a large list of servers and databases to identify any that are overdue for backups.  Particularly helpful for highlighting new databases that have been deployed without getting included in your backup processing.  I also like Space Analyzer to keep an eye on disk space consumed by database files. Idera SQL Job Manager This free tool provides a nice calendar view of SQL Server Job Schedules, but to a degree, you also get what you pay for.  We will be purchasing SQL Sentry Event Manager later this year as an even better job schedule reviewer/manager.  But in the meantime, this at least gives me a good view on potential resource conflicts across multiple instances of SQL Server. DBFViewer 2000 I inherited a couple of FoxPro databases that I have to keep an eye on occasionally and have not yet been able to migrate them to SQL Server. Balsamiq Mockups We are still in evaluation-mode on this tool, but I really like it as a quick UI mockup tool that does not require Visual Studio, so someone other than a programmer can do UI design.  The interface looks hand-drawn which definitely has some psychological benefits when communicating to users, too. FeedDemon I have to stay on top of my WAY TOO MANY blog subscriptions somehow.  I may read blogs on a couple of different computers, and FeedDemon’s integration with Google Reader allows me to keep them all in sync.  I don’t particularly like the Google Reader interface, or the fact that it always wanted to mark articles as read just because I scrolled past them.  FeedDemon solves this problem for me, and provides a multi-tabbed interface which is good because fairly frequently one blog will link to something else I want to read, and I can end up with a half-dozen open tabs all from one article. Synergy+ In my office, I run four monitors across two computers all with one mouse and keyboard.  Synergy is the magic software that makes this work. TweetDeck I’m not the most active Tweeter in the world, but when I want to check-in with the Twitterverse, this really helps.  I have found the #sqlhelp and #PoshHelp hash tags particularly useful, and I also have columns setup to make it easy to monitor #sqlpass, #PASSProfDev, and short term events like #sqlsat68.   Whew!  That’s a lot.  No wonder it took me a couple of days to get everything setup the way I wanted it.  Oh, that and actually getting some work accomplished at the same time.  Anyway, I know that is a huge dump of info, and most people never make it here to the end, so for those who did, let me say, CONGRATULATIONS, you made it! I hope you’ll find a new tool or two to make your work life a little easier.

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