LINQ: adding where clause only when a value is not null

Question

I know a typical way is like this:

IQueryable query = from staff in dataContext.Staffs;
if(name1 != null)
{
     query = from staff in query where (staff.nam         


        

Answer 1

I've seen this pattern in standard SQL, and it seems useful if you have several parameters that may be NULL. For example:

SELECT * FROM People WHERE ( @FirstName IS NULL OR FirstName = @FirstName )
                       AND ( @LastName IS NULL OR LastName = @LastName )

If you see this in LINQ, it's possible they just blindly translated their old SQL-queries.