Linq To SQL - Specified cast is not valid - SingleOrDefault()

Posted by NullReference on Stack Overflow See other posts from Stack Overflow or by NullReference
Published on 2010-03-12T21:53:12Z Indexed on 2010/03/12 21:57 UTC
Read the original article Hit count: 775

Filed under:

LINQ

I am trying to do the following...

Request request = (from r in db.Requests where r.Status == "Processing" && r.Locked == false select r).SingleOrDefault();

It is throwing the following exception...

Message: Specified cast is not valid.

StackTrace: at System.Data.Linq.SqlClient.SqlProvider.Execute(Expression query, QueryInfo queryInfo, IObjectReaderFactory factory, Object[] parentArgs, Object[] userArgs, ICompiledSubQuery[] subQueries, Object lastResult) at System.Data.Linq.SqlClient.SqlProvider.ExecuteAll(Expression query, QueryInfo[] queryInfos, IObjectReaderFactory factory, Object[] userArguments, ICompiledSubQuery[] subQueries) at System.Data.Linq.SqlClient.SqlProvider.System.Data.Linq.Provider.IProvider.Execute(Expression query) at System.Data.Linq.DataQuery1.System.Linq.IQueryProvider.Execute[S](Expression expression) at System.Linq.Queryable.SingleOrDefault[TSource](IQueryable1 source) at GDRequestProcessor.Worker.GetNextRequest()

Can anyone help me? Thanks in advance!

Related posts about LINQ

LINQ to SQL, LINQ to XML and Accessing DataTable using LINQ

as seen on C# Corner - Search for 'C# Corner'
This article demonstrates how to use LINQ on DataTable, XML Data using LINQ to XML and SQL server data base using LINQ to SQL Classes. >>> More
Exception with Linq2SQL Query

as seen on Stack Overflow - Search for 'Stack Overflow'
I am running a query using Linq2SQL that comes down to following query: DateTime? expiration = GetExpirationDate(); IQueryable<Persons> persons = GetPersons(); IQueryable<Items> subquery = from i in db.Items where i.ExpirationDate >= expiration … >>> More
What is Linq?

as seen on ASP.net Weblogs - Search for 'ASP.net Weblogs'
The way data can be retrieved in .NET. LINQ provides a uniform way to retrieve data from any object that implements the IEnumerable<T> interface. With LINQ, arrays, collections, relational data, and XML are all potential data sources. Why LINQ?With LINQ, you can use the same syntax to retrieve… >>> More
Subsonic 3 LINQ vs LINQ to SQL

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I am using SQL Server 2005 in a project. I have to decide about datalayer. I would like to use LINQ in my project. I saw SubSonic 3 supporting LINQ and I also have option for LINQ to SQL, because i can have typed lists from LINQ to SQL. I am wondering what is different between LINQ to SQL and… >>> More
Mixing Silverlight-Specific System.Xml.Linq dll with Non-Silverlight System.Xml.Linq dll

as seen on Stack Overflow - Search for 'Stack Overflow'
I have a Logic layer that references Silverlight's System.Xml.Linq dll and a GUI that is in WPF (hence using the non-Silverlight System.Xml.Linq dll). When I attempt to pass an XElement from GUI project to a method in the Logic project, I am getting (basically) "XElement is not of type XElement" errors… >>> More

Developer IT