From: Tom Lane <tgl@sss.pgh.pa.us>
To: =?gb2312?B?t7a5+sza?= <fanguoteng@highgo.com>
cc: "pgsql-admin@lists.postgresql.org" <pgsql-admin@lists.postgresql.org>
Subject: Re: Where to change the column width in RelOptInfo data
In-reply-to: <f372513e8bd843d6a424f951ea14dfa9@EX01.highgo.com>
References: <f372513e8bd843d6a424f951ea14dfa9@EX01.highgo.com>
Comments: In-reply-to =?gb2312?B?t7a5+sza?= <fanguoteng@highgo.com>
	message dated "Wed, 25 Jul 2018 01:29:58 -0000"
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Date: Wed, 25 Jul 2018 10:35:31 -0400
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=3D?gb2312?B?t7a5+sza?=3D <fanguoteng@highgo.com> writes:
> I use a postgres extension plugin pg_strom to generate the plan. I selec=
t one column =C2=A1=C2=B0avg(c_acctbal)=C2=A1=C2=B1 in the SQL, and the ge=
nerated plan changes to select two column =C2=A1=C2=B0c_acctbal, c_phone=C2=
=A1=C2=B1.

I think you'd be better off doing that sort of thing in the rewriter
somewhere.  Wherever you tried to put it in the planner is clearly
too late.

			regards, tom lane