Thanks for the replies.

Yes, i want to display all employees (from tblEmployees) whose employee code is not cancelled in tblEmployeeCodes.

Sorry, here is the info. you requested:

SELECT FirstName,LastName,EmpEmail,EmpCode

FROM tblEmployees (7990)

SELECT FirstName,LastName,EmpEmail,EmpCode

FROM tblEmployees

WHERE Subgroup = @Subgroup (VARIES ACCORDING TO @SubGroup)

SELECT EmpCode FROM tblEmpCodes where cancelled IS NOT NULL (1906)

Select EmpCode

FROM tblEmployees

WHERE...

All of the queries return rows except this one:

Select EmpCode

FROM tblEmployees

WHERE EmpCode NOT IN (select EmpCode from tblEmpCodes where cancelled is NOT NULL)

No rows returned.