Re: mySQL performance problem on subqueries

[Peter Brawley]

Did you try decorrelating the subquery, something like (untested) ...

SELECT t1.*, COUNT(t2.c001)
FROM mytable t1
INNER JOIN mytable t2 ON t2.c003 BETWEEN t1.c003 AND t1.c004
WHERE t1.c005 = 121
GROUP BY t1.c003;

PB