(sent to general users mailing list yesterday - but perhaps this is a more suitable audience?)
In PG16.4, we have a table of key/pair data (around 30M rows) where there are about 7 distinct keys and each has a conditional or partial index on them (the distribution is different for each key/value pair combination). I've found that when we have a query that uses an OR then those partial indexes are used but not if the query is written to use ANY/IN, which is more convenient from a programmer POV (especially any with 3rd party query generators etc.). Naturally, the result sets returned by the queries are identical due to the filter semantics of any of the 3 solution variants.
Is there any trick I can do to get the planner to make use of the conditional/partial index? Or is this simply an unoptimised code path yet to be exploited!?
Cheers,
Jim
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Jim Vanns Principal Production Engineer Industrial Light & Magic, London