.NET Tutorials, Forums, Interview Questions And Answers
Welcome :Guest
Sign In
Win Surprise Gifts!!!

Top 5 Contributors of the Month
david stephan
Gaurav Pal
Post New Web Links

Data Points: LINQ Projection Queries and Alternatives in WCF Services

Posted By:      Posted Date: August 21, 2010    Points: 0   Category :ASP.Net

LINQ's ability to project randomly shaped data into anonymous types can be a blessing and a source of frustration, says Julie Lerman. It's great when you just need to grab a special view of your data, but it can be problematic in certain circumstances. She explains what the limitations are and how to get around them.

Julie Lerman

MSDN Magazine May 2010

View Complete Post

More Related Resource Links

Data Points: Precompiling LINQ Queries


Did you know that by precompiling LINQ queries you might actually be degrading your app's performance if you're not careful? Julie Lerman explains how to ensure you're not re-precompiling queries each time and losing the expected performance benefits across post-backs, short-lived service operations and other code where critical instances are going out of scope.

Julie Lerman

MSDN Magazine March 2010

Data Points: Using Silverlight 2 With ADO.NET Data Services


ADO.NET Data Services and Silverlight make a powerful combination, but to make them work well together, there are a few things you need to understand. Here, John Papa explains.

John Papa

MSDN Magazine April 2009

Data Points: Standard Query Operators with LINQ


LINQ to Objects and LINQ to Entities have an arsenal of Standard Query Operators that operate on sequences to perform a wide variety of operations.

John Papa

MSDN Magazine March 2008

Data Points: Report Controls in SQL Server 2005 Reporting Services


Reporting has always been one of the dark arts of development. The tools typically seem to do just enough to get you to a certain point, then leave you to find workarounds to solve more complex issues.

John Papa

MSDN Magazine July 2006

Data Points: Designing Reports with SQL Server Reporting Services 2005


Many applications require some degree of integration with a reporting tool. A good solution, SQL ServerT Reporting Services 2005, provides Web-based reports and can be integrated into both Windows® Forms and Web-based applications.

John Papa

MSDN Magazine June 2006

Is there a way to query entity based on multiple filter criteria? WCF Data Services, Linq to Entiti


Instead of:

DW_CMSOPEN dwc = new DW_CMSOPEN(new Uri("http://acctdev02/WCFDataService/EmployeeService.svc"));

dwc.Credentials = System.Net.CredentialCache.DefaultCredentials;

var employees = from emp in dwc.Employees 
             where emp.DEPT == "123"
             select emp;

I'd like the linq query to resemble:

var employees = from emp in dwc.Employees
              where emp.DEPT // in {"123", "456", etc}
              select emp;

Linq - add data to database then email user the details


Hi all

I'm not sure how to structure the code for this but what I want to do is be able to add data to a database, and once this has completed successfully, then email the user to say the details have been added successfully to the database.

I need to:

1. Check that the relevant data has been added into the database then

2. Email the details of the relevant data when completed. 


Thanks in advance for your help,




The type 'System.Data.Linq.DataContext' is defined in an assembly that is not referenced. You must



This is frustrating, and I don't know how to solve it.

I have a strange problem. I am adding a LinqDatasource object, and set the context:

        protected void LinqDataSource_ContextCreating(object sender, LinqDataSourceContextEventArgs e)
            e.ObjectInstance = new KaruselaDataContext(ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString);

Then I get this error:
The type 'System.Data.Linq.DataContext' is defined in an assembly that is not referenced. You must add a reference to assembly 'System.Data.Linq, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089'.


On web.config I already have this:
<add assembly="System.Data.Linq, Version=, Culture=neutral, PublicKeyToken=b77a5c561934e089"/>

NOTE: The datacontext is in a different project (DLL proect) where I added a refernce to System.Data.Linq.

is there another way adding a refernce to a web project? or only though teh web.config?


Which tier do Linq queries belong?


Started in middle of a new project.  Our design architecture uses an n-tier (not MVC - no controllers) structure with Presentation, Data, Business and Service tiers.  However the lead analyst has the majoriety of code all in the Business tier claiming it all contains Business logic.  Our data tier is nothing more than a single .dbml model of the primary database to support all of the Linq queries in the Business tier.  To my mind Linq queries and classes they use are data access and belong in the data tier  but our lead analyst says they contain business logic therefore have to be in business layer.  

OData and AtomPub: Building an AtomPub Server Using WCF Data Services


Learn how to use the AtomPub protocol to pump up your blogs. Chris Sells includes a practical demonstration of mapping so you can expose a standard AtomPub service from a Web site and use Windows Live Writer to provide a rich editing experience against the service.

Chris Sells

MSDN Magazine August 2010

Data Points: Deny Table Access to the Entity Framework Without Causing a Mutiny


Julie Lerman shows database administrators how to limit access to databases from the Entity Framework by allowing it to work only with views and stored procedures instead of tables-without impacting application code or alienating developers.

Julie Lerman

MSDN Magazine August 2010

Data Points: Windows Azure Table Storage - Not Your Father's Database


Let go of your traditional relational database thinking if you want to understand how Windows Azure Table storage works, says Julie Lerman. Luckily for you, she's done the hard work to grasp the new concepts and help you get up to speed.

Julie Lerman

MSDN Magazine July 2010

VS 2010: Entity Framework 4.0 and WCF Data Services 4.0 in Visual Studio 2010


Elisa Flasko takes you through a sample weblog application to demonstrate how new improvements in Entity Framework and WCF Data Services work together to simplify the way data is modeled, consumed and produced in Visual Studio 2010.

Elisa Flasko

MSDN Magazine April 2010

Cutting Edge: ASP.NET Ajax Library and WCF Data Services


This month Dino takes a look at the JavaScript components coming in the ASP.NET Ajax Library and explains how they can be used for effective client-side data access.

Dino Esposito

MSDN Magazine March 2010

Cloud Security: Crypto Services and Data Security in Windows Azure


Many early adopters cloud platforms have questions about security. We review some of the cryptography services and providers in Windows Azure along with some security implications for applications in the cloud.

Jonathan Wiggs

MSDN Magazine January 2010

Data Points: Data Validation with Silverlight 3 and the DataForm


In this month's column, John Papa shows you how the DataForm control works and how it can be customized.  He presents in detail a sample application that uses several features to bind, navigate, edit and validate data using the DataForm.

John Papa

MSDN Magazine October 2009

SQL Data Services: The Relational Database of the Azure Services Platform


This article shows you the new face of SQL Data Services, explores its architecture, and shows how it is truly an extension of SQL Server in the cloud.

David Robinson

MSDN Magazine August 2009

ASP.NetWindows Application  .NET Framework  C#  VB.Net  ADO.Net  
Sql Server  SharePoint  Silverlight  Others  All   

Hall of Fame    Twitter   Terms of Service    Privacy Policy    Contact Us    Archives   Tell A Friend