perf(db): Sort data for IN before chunking #45058
Merged
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Summary
Nextcloud sends chunks of
DELETE FROM oc_filecache WHERE parentid IN (....long list...)
and sometimes MariaDB does not seem to pick up the index. Apparently this may happen when the query analyzer thinks it's cheaper to scan the table than to traverse the index. If we put the data of the chunks closer together, we can hopefully convince the db that the index is the faster choice.@juliushaertl @nickvergessen as it was suggested to us.
I don't know how to trigger this code with lots of data so this is more or less untested.
Checklist