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From: Arne Roland <[email protected]>
To: Richard Guo <[email protected]>
To: Andrei Lepikhov <[email protected]>
Cc: PostgreSQL-development <[email protected]>
Subject: Re: A performance issue with Memoize
Date: Thu, 18 Jan 2024 07:39:09 +0100
Message-ID: <[email protected]> (raw)
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Hi Richard,

I can tell this a real world problem. I have seen this multiple times in 
production.

The fix seems surprisingly simple.

I hope my questions here aren't completely off. I still struggle to 
think about the implications.

I wonder, if there is any stuff we are breaking by bluntly forgetting 
about the subplan params. Maybe some table valued function scan within a 
subquery scan? Or something about casts on a join condition, that could 
be performed differently?

I wasn't able to construct a problem case. I might be just missing 
context here. But I am not yet fully convinced whether this is safe to 
do in all cases.

Regards
Arne

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