Re: [HACKERS] CTE inlining - Mailing list pgsql-hackers

From Alvaro Herrera
Subject Re: [HACKERS] CTE inlining
Date
Msg-id 20170504173339.6zrrdrtklyr6d4ih@alvherre.pgsql
Whole thread Raw
In response to Re: [HACKERS] CTE inlining  (Andrew Dunstan <andrew.dunstan@2ndquadrant.com>)
Responses Re: [HACKERS] CTE inlining  (Andrew Dunstan <andrew.dunstan@2ndquadrant.com>)
Re: [HACKERS] CTE inlining  (Joe Conway <mail@joeconway.com>)
Re: [HACKERS] CTE inlining  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
Andrew Dunstan wrote:

> Hadn't though about LATERAL, good point. Still, there will be other cases.

I'm not sure what your point is.  We know that for some cases the
optimization barrier semantics are useful, which is why the proposal is
to add a keyword to install one explicitely:
        with materialized r as        (           select json_populate_record(null::mytype, myjson) as x           from
mytable       )        select (x).*        from r;
 

this would preserve the current semantics.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services



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