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From: Scott Ribe <[email protected]>
To: Doug Reynolds <[email protected]>
Cc: Pgsql-admin <[email protected]>
Subject: Re: checking for a NULL date in a partitioned table kills performance
Date: Fri, 23 Aug 2024 10:08:49 -0600
Message-ID: <[email protected]> (raw)
In-Reply-To: <010001917fe71552-589dbc9b-2c78-4a0d-8405-040db3cc09d7-000000@email.amazonses.com>
References: <[email protected]>
	<010001917fe71552-589dbc9b-2c78-4a0d-8405-040db3cc09d7-000000@email.amazonses.com>

> On Aug 23, 2024, at 9:42 AM, Doug Reynolds <[email protected]> wrote:
> 
> The only difference is that you would be reading from one index instead of two, which could be more efficient. 

Ah yes, that's a good point to take into consideration in such a case.

In the one at hand though, if statistics are correct, neither index is going to be used, given the 90% of rows with NULL values. Using an index would just waste time compared to a simple sequential scan.

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