2017-04-30 6:28 GMT+02:00 Tom Lane <t...@sss.pgh.pa.us>: > Craig Ringer <craig.rin...@2ndquadrant.com> writes: > > - as you noted, it is hard to decide when it's worth inlining vs > > materializing for CTE terms referenced more than once. > > [ raised eyebrow... ] Please explain why the answer isn't trivially > "never". > > There's already a pretty large hill to climb here in the way of > breaking peoples' expectations about CTEs being optimization > fences. Breaking the documented semantics about CTEs being > single-evaluation seems to me to be an absolute non-starter. > > why we cannot to introduce GUC option - enable_cteoptfence ?
Regards Pavel > regards, tom lane > > > -- > Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) > To make changes to your subscription: > http://www.postgresql.org/mailpref/pgsql-hackers >
