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From: Konstantin Knizhnik <k.knizhnik@postgrespro.ru>
To: pgsql-hackers@postgresql.org
Subject: Re: Cached plans and statement generalization
Date: Wed, 26 Apr 2017 10:00:17 +0300
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On 26.04.2017 00:47, Andres Freund wrote:
> On 2017-04-25 21:11:08 +0000, Doug Doole wrote:
>> When I did this in DB2, I didn't use the parser - it was too expensive. I
>> just tokenized the statement and used some simple rules to bypass the
>> invalid cases. For example, if I saw the tokens "ORDER" and "BY" then I'd
>> disallow replacement replacement until I hit the end of the current
>> subquery or statement.
> How did you manage plan invalidation and such?

The same mechanism as for prepared statements.
Cached plans are linked in the list by SaveCachedPlan function and are 
invalidated by PlanCacheRelCallback.



> - Andres
>
>

-- 
Konstantin Knizhnik
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company



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