Fwd: [PERFORM] Loose Index Scans by Planner? - Mailing list pgsql-hackers

From Jeff Janes
Subject Fwd: [PERFORM] Loose Index Scans by Planner?
Date
Msg-id CAMkU=1zoosLAGBkY=rDpA1KvtYFvWbu=cUkyFKZGv9eKw7oKiQ@mail.gmail.com
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I'd like to create a ToDo item for "loose index scans" or "skip
scans", when the lead column has low cardinality and is not used in
the where clause.  This case can potentially be optimized by using the
index as if it were a collection of N "partitioned" indexes, where N
is the cardinality of the lead column.  Any objections?

I don't really have a detailed plan on how to do it.  I expect the
planner part would be harder than the execution part.

See "[PERFORM] Loose Index Scans by Planner" thread.

Thanks,

Jeff



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