Re: Binary search in ScalarArrayOpExpr for OR'd constant arrays

David Rowley <dgrowleyml@gmail.com>

From: David Rowley <dgrowleyml@gmail.com>
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Cc: James Coleman <jtc331@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2020-04-25T21:41:39Z
Lists: pgsql-hackers
On Sun, 26 Apr 2020 at 00:40, Tomas Vondra <tomas.vondra@2ndquadrant.com> wrote:
> This reminds me our attempts to add bloom filters to hash joins, which I
> think ran into mostly the same challenge of deciding when the bloom
> filter can be useful and is worth the extra work.

Speaking of that, it would be interesting to see how a test where you
write the query as IN(VALUES(...)) instead of IN() compares. It would
be interesting to know if the planner is able to make a more suitable
choice and also to see how all the work over the years to improve Hash
Joins compares to the bsearch with and without the bloom filter.

David



Commits

  1. Use a hash table to speed up NOT IN(values)

  2. Speedup ScalarArrayOpExpr evaluation