Isn't the following:
SELECT * FROM t1, t2 where tl.ID=t2.foreignKey;
logically equivalent to:
SELECT * FROM t1 LEFT JOIN t2 ON t1.ID=t2.foreignKey WHERE t2.ID IS NOT
NULL;
Because I had a query in the first format that took about two minutes to
run on MySQL, and then I changed it into the second format and it ran in
about two seconds. If LEFT JOINs are so much faster, why doesn't MySQL
take queries in the first format and convert them into the second
format? The first format is easier to read, and more logical, so it would
be the preferred format for actually writing queries.
-Bennett
[EMAIL PROTECTED] http://www.peacefire.org
(425) 649 9024
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