Re: Expression Evaluator used for creating the plan tree / stmt ?

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Alvaro Herrera <alvherre(at)commandprompt(dot)com>
Cc: Vaibhav Kaushal <vaibhavkaushal123(at)gmail(dot)com>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: Expression Evaluator used for creating the plan tree / stmt ?
Date: 2011-05-25 15:04:38
Message-ID: 5774.1306335878@sss.pgh.pa.us
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Alvaro Herrera <alvherre(at)commandprompt(dot)com> writes:
> Excerpts from Vaibhav Kaushal's message of mi may 25 05:52:32 -0400 2011:
>> If the above is confusing, I just want to ask: "Is expression evaluator,
>> even in part responsible for {PLANNEDSTMT creation?"

> Yeah, as far as I understood Tom's talk, the expr evaluator is used to
> reduce some expressions to constants and such.

The planner would never call it with an expression containing a Var,
though.

regards, tom lane

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