On 05/03/2017 04:42 PM, Tom Lane wrote: > Alvaro Herrera <alvhe...@2ndquadrant.com> writes: >> Yawn. So, we have not achieved the stated goal which was to get rid of >> the ugly clause in the middle of the command; moreover we have gained >> *yet another* clause in the middle of the command. Is this really an >> improvement? We're trading this >> CREATE STATISTICS s1 WITH (dependencies, ndistinct, options) ON (a, b) >> FROM t1 WHERE partial-stuff; >> for this: >> CREATE STATISTICS s1 USING (dependencies, ndistinct) WITH (options) ON >> (a, b) FROM t1 WHERE partial-stuff; >> Can we decide by a show of hands, please, whether we're really on board >> with this change? > That seems totally messy :-( > > I can't see any good reason why "WITH (options)" can't be at the end of > the query. WITH is a fully reserved word, there is not going to be any > danger of a parse problem from having it follow the FROM or WHERE clauses. > And the end is where we have other instances of "WITH (options)". > > It also seems like we don't need to have *both* fully-reserved keywords > introducing each clause *and* parentheses around the lists. Maybe > dropping the parens around the stats-types list and the column-names > list would help to declutter? (But I'd keep parens around the WITH > options, for consistency with other statements.) > > One other point is that as long as we've got reserved keywords introducing > each clause, there isn't actually an implementation reason why we couldn't > accept the clauses in any order. Not sure I want to document it that way, > but it might not be a bad thing if the grammar was forgiving about whether > you write the USING or ON part first ... > >
+1 for allowing arbitrary order of clauses. I would document it with the USING clause at the end, and have that be what psql supports and pg_dump produces. Since there are no WITH options now we should leave that out until it's required. cheers andrew -- Andrew Dunstan https://www.2ndQuadrant.com PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
