Question

What is the most performant way to count items on a table using EF 4.1?

this.context.MyTable.Count(x.idTenant == 5);

or

 this.context.MyTable.Where(x.idTenant == 5).Count();

Any other way to Count entities in a table, being it more performant?

Answer 1

According to the output from Linq, the expressions are equal in the SQL they generate:

SELECT COUNT(*) AS [value]
FROM [MyTable] AS [t0]
WHERE [t0].[idTenant] = @p0