On 25 Feb 2004 at 13:09, Eric Scuccimarra wrote:
> Select *
> FROM Table1 as a
> INNER JOIN Table2 as b ON (a.ID = b.ID or (a.Field1 = b.Field1 and
> a.Field2 = b.Field2)) WHERE bla bla bla
It's hard to know without seeing the indexes and the full WHERE
clause, but part of the problem could be that MySQL can't use an
index for the join because of the "OR". One possibility would be to
break in into two queries and use a UNION:
( SELECT * FROM Table1 a INNER JOIN Table2 b ON a.ID = b.ID
WHERE <condition> )
UNION
( SELECT * FROM Table1 a INNER JOIN Table2 b
ON a.Field1 = b.Field1 AND a.Field2 = b.Field2
WHERE <condition> )
ORDER BY <whatever>;
--
Keith C. Ivey <[EMAIL PROTECTED]>
Tobacco Documents Online
http://tobaccodocuments.org
--
MySQL General Mailing List
For list archives: http://lists.mysql.com/mysql
To unsubscribe: http://lists.mysql.com/[EMAIL PROTECTED]
