Re: Improving planner variable handling - Mailing list pgsql-hackers

From Gregory Stark
Subject Re: Improving planner variable handling
Date
Msg-id 87wsgabuhz.fsf@oxford.xeocode.com
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In response to Re: Improving planner variable handling  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Improving planner variable handling
Re: Improving planner variable handling
List pgsql-hackers
Tom Lane <tgl@sss.pgh.pa.us> writes:

> * When we have a non-nullable expression in a sub-select's targetlist,
> and it's below an outer join, replace the expression by
>     CASE WHEN flag_var THEN original_expression ELSE NULL END
> and then flatten as normal.

I don't understand how this gets you any further ahead. Doesn't it just move
the problems you have now with the original_expression to flag_var instead?

--  Gregory Stark EnterpriseDB          http://www.enterprisedb.com Ask me about EnterpriseDB's On-Demand Production
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