Re: more than one union or intersect operator

Wong Chung Yin wrote:
> If there are many "union" and "intersect" in a SQL statement, how can
> I state the precedence of union and intersect.

just like you state precendence in "and"s and "or"s: use parentheses.

(select id from database where keyword = 'computer'  union
 select id from database where keyword = 'science' )
intersect
select id from database where keyword = 'course'

HTH
janet

(for email remove -SPAM-BLOCK from address) Received on Tue Feb 18 1997 - 00:00:00 CST