Linq to SQL - Multiple where clauses at runtime

I am trying to accomplish this but only my first where clause is getting used when the query ru开发者_JAVA百科ns.

This needs to for for .Net 3.5 so the WhereIf in 4.0 is not usable.

var query =
    from tb in dataContext.TableOne
    where tb.DateTimeCreated >= fromDate && 
        tb.DateTimeCreated <= toDate.AddDays(1) 
    select tb;

if (!string.IsNullOrEmpty(reference))
{
    query.Where(tb => tb.Reference = reference));
}

  if (!string.IsNullOrEmpty(reference))
        query = query.Where(tb => tb.Reference = reference));

Try

Just do it in "one"

var query = (from tb in dataContext.TableOne
                      where (tb.DateTimeCreated >= fromDate && tb.DateTimeCreated <= toDate.AddDays(1)) && (string.IsNullOrEmpty(reference) || tb.Reference == reference)
                      select tb
               );

or as Ives says, do:

query = query.Where(...)