On Sun, Nov 3, 2013 at 3:01 AM, Tom Lane <t...@sss.pgh.pa.us> wrote: > Michael Paquier <michael.paqu...@gmail.com> writes: >> On Sat, Nov 2, 2013 at 10:28 PM, Andrew Dunstan <and...@dunslane.net> wrote: >>> What exactly would be the point? Indexes are automatically maintained by >>> postgres. Something that isn't doesn't seem to me to qualify for the >>> description of "index". > >> Perhaps an index without data that could be used by the planner for >> automatic query tuning to evaluate how a query could run if the index >> exists? Like the concept of hypothetical indexes or something like the >> possibility to do a CREATE/ALTER INDEX ... WITH [ NO ] DATA. > > But we already provide support for hypothetical indexes via planner > plugins. Why would you need an actual empty index underlying that? Using only the planner hook? Forgive my lack of knowledge of the planner, but this does not seem really straight-forward :)
One of the only documentation I found about hypothetical indexes was this tutorial of PGCon 2010: http://www.inf.puc-rio.br/~postgresql/conteudo/projeto1/Tutorial9/TUTORIAL_9_0_1.pdf But in this case the grammar of CREATE INDEX has been modified, so core code was changed as well. Of course if Naman has something else in mind... -- Michael -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
