After viewing the suggested solutions, i've came up with this.


1: select table1.documentno,
2: table2.refno,
3: table2.chequestatus
4: from table1,table2
5: where table2.tid = table1.tid
6: and table1.documentno = ?
7: and ( table2.refno = ?
8: OR table2.refno is null)

This seems to work fine and gives the best performance from my
observation since i have table2.refno indexed.
Thanks again guys!!

Regards,
Marvin