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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Sbob <sbob@quadratum-braccas.com>
cc: Rui DeSousa <rui.desousa@icloud.com>,
        "pgsql-performance@lists.postgresql.org"
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Subject: Re: checking for a NULL date in a partitioned table kills performance
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Comments: In-reply-to Sbob <sbob@quadratum-braccas.com>
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Sbob <sbob@quadratum-braccas.com> writes:
> 29 million of the 32 million rows in the table have NULL for contract_date

[ blink... ]  So your query is selecting at least 29/32nds of the
table, plus however much matches the contract_date > '2022-01-01'
alternative.  I'm not sure how you expect that to be significantly
cheaper than scanning the whole table.

			regards, tom lane