Query is executed although sub-query is error?
xi`tinSep 6 2009 — edited Sep 7 2009Hi everyone,
I have a problem want to explained.
My sub-query show an error if it's executed alone: "ORA-00904: invalid column name"
SELECT id FROM table_A WHERE field1 = 'exam' (field1 is not exist)
But when execute with:
SELECT * FROM table_B WHERE id IN (SELECT id FROM table_A WHERE field1 = 'exam')
it's ok, although we don't have any data filtered. I don't known the reason why? Can anyone explain this?
Thanks a lot!