MySQL is an incredibly frustrating database when it comes to joins.. for whatever reason it seems to crawl to a halt when it comes to putting two tables together. So, in general, writing two seperate queries with Perl logic in between is often faster.

Because you are doing a SELECT MIN() operation it is almost a guarantee that you cannot write this as a single query.

MySQL 4 offers some hope, though, with transactions. You could create a temporary table, fill it using the SELECT MIN() operation, and then LEFT JOIN that into your main query, finally delete the table and lastly ROLLBACK the transaction.

Either way it is going to get ugly! Good luck!

In reply to Re: Query rewriting question by Anonymous Monk
in thread Query rewriting question by Anonymous Monk

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