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Home -> Community -> Usenet -> c.d.o.misc -> Why the "where NOT EXISTS" does not work?
I have 2 tables say A_table, B_table. They both have some common
columns. The A_Table has some rows that with the column not appearing
in B_table. I tried to use following to find out what appears in
A_talbe but not in B_table.
select a
from A_table
where NOT EXISTS
( select a
from B_table
where ..);
and it always return 0 row. What went wrong? Need Help Thanks.
C Chang Received on Tue Oct 23 2001 - 22:19:05 CDT