PRB: Cannot Find NULL Records with Parameterized Query

RESOLUTION

Before calling the code that executes the query, use an IF statement that checks the value of the parameter. If the value is NULL, run a different query that specifically looks for a NULL value, otherwise run the original, parameterized query.

Example:

   Dim p1 as long
   dim r1 as recordset
   dim SQLstring as string
   dim p1 as long

   if p1 = NULL then
       SQLstring = "SELECT Table1.Field1 FROM Table1  _
       WHERE (((Table1.Field1) Is Null));"
       'Looking specifically for a Null
   else
       SQLstring = "SELECT Table1.Field1 FROM Table1 _
       WHERE (((Table1.Field1)=[" & p1 & "]));"
       'Parameterized query
   end if

   set r1 = MyDatabase.openrecordset(SQLstring, dbOpenDynaset)