Thanks Tom.

The folowing SQL replaces Sql_3
SELECT fld_a + fld_b FROM tbl_1 WHERE fld_a + fld_b IN (SELECT fld_a + fld_b FROM tbl_2 HAVING DELETED()) UNION SELECT fld_a + fld_b FROM tbl_1 WHERE DELETED().

BTW - BUG WARNING
We found that Sql_3 worked in VFP 6 as written the first time, so we are assuming that VFP 3 has a bug.

Thanks to all who chipped in.

Todd Cottengim
Alpine Land Information Services