Fwd: [PERFORM] Loose Index Scans by Planner?

From: Jeff Janes <jeff(dot)janes(at)gmail(dot)com>
To: pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Fwd: [PERFORM] Loose Index Scans by Planner?
Date: 2012-09-02 21:53:45
Message-ID: CAMkU=1zoosLAGBkY=rDpA1KvtYFvWbu=cUkyFKZGv9eKw7oKiQ@mail.gmail.com
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers pgsql-performance

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

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Tomas Vondra 2012-09-02 22:40:12 Re: PATCH: pgbench - random sampling of transaction written into log
Previous Message Jeff Janes 2012-09-02 21:39:27 Re: [PERFORM] pg_dump and thousands of schemas

Browse pgsql-performance by date

  From Date Subject
Next Message Robert Haas 2012-09-03 04:37:28 Re: [PERFORM] pg_dump and thousands of schemas
Previous Message Jeff Janes 2012-09-02 21:39:27 Re: [PERFORM] pg_dump and thousands of schemas