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powa-team / pg_qualstats

A PostgreSQL extension for collecting statistics about predicates, helping find what indices are missing
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Change query ID from 32 bits to 64 bits #16

Closed anayrat closed 6 years ago

anayrat commented 6 years ago

query ID is now on 64 bits (to avoid collisions). From commit cff440d368 :

This takes advantage of the infrastructure introduced by commit 81c5e46c490e2426db243eada186995da5bb0ba7 to greatly reduce the likelihood that two different queries will end up with the same query ID. It's still possible, of course, but whereas before it the chances of a collision reached 25% around 50,000 queries, it will now take more than 3 billion queries.

Backward incompatibility: Because the type exposed at the SQL level is int8, users may now see negative query IDs in the pg_stat_statements view (and also, query IDs more than 4 billion, which was the old limit).