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A MySQL query needs the results of a subquery in different places, like this: SELECT COUNT(*),(SELECT hash FROM sets WHERE ID=1) FROM sets WHERE hash=(SELECT hash FROM sets WHERE ID=1) and XD=2; Is there a way to avoid the double execution of the subquery (SELECT hash FROM sets WHERE ID=1) ? The result of the subquery always returns an valid hash value. It is important that the result of the main query also includes the HASH. First I tried a JOIN like this: SELECT COUNT(*), m.hash FROM sets s INNER JOIN sets AS m WHERE s.hash=m.hash AND id=1 AND xd=2; If XD=2 doesn't match a row, the result is: +----------+------+ | count(*) | HASH | +----------+------+ | 0 | NULL | +----------+------+ Instead of something like (what I need): +----------+------+ | count(*) | HASH | +----------+------+ | 0 | 8115e| +----------+------+ Any ideas? Please let me know! Thank you in advance for any help. //Edit: finally that query only has to count all the entries in an table which has the same hash value like the entry with ID=1 and where XD=2. If no rows matches that (this case happend if XD is set to an other number), so return 0 and simply hash value.

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