On 23 June 2013 03:16, Stephen Frost <sfrost@snowman.net> wrote:
> Still doesn't really address the issue of dups though.
Checking for duplicates in all cases would be wasteful, since often we
are joining to the PK of a smaller table.
If duplicates are possible at all for a join, then it would make sense
to build the hash table more carefully to remove dupes. I think we
should treat that as a separate issue.
-- Simon Riggs http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training & Services