Re: Cached plans and statement generalization

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
>
>

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