On Wed, Dec 30, 2015 at 3:14 AM, Michael Paquier <michael.paqu...@gmail.com> wrote: > On Sun, Dec 20, 2015 at 8:08 AM, Michael Paquier > <michael.paqu...@gmail.com> wrote: >> On Sun, Dec 20, 2015 at 6:24 AM, Tom Lane <t...@sss.pgh.pa.us> wrote: >>> 2. I believe that a very large fraction of the TailMatches() rules really >>> ought to be Matches(), ie, they should not consider matches that don't >>> start at the start of the line. And there's another bunch that could >>> be Matches() if the author hadn't been unaccountably lazy about checking >>> all words of the expected command. If we converted as much as we could >>> that way, it would make psql_completion faster because many inapplicable >>> rules could be discarded after a single integer comparison on >>> previous_words_count, and it would greatly reduce the risk of inapplicable >>> matches. We can't do that for rules meant to apply to DML statements, >>> since they can be buried in WITH, EXPLAIN, etc ... but an awful lot of >>> the DDL rules could be changed. > > Yep, clearly. We may gain a bit of performance by matching directly > with an equal number of words using Matches instead of a lower bound > with TailMatches. I have looked at this thing and hacked a patch as > attached.
I see that you changed INSERT and DELETE (but not UPDATE) to use MatchesN rather than TailMatchesN. Shouldn't these stay with TailMatchesN for the reason Tom gave above? -- Thomas Munro http://www.enterprisedb.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
