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Re: Poor row estimates from planner, stat `most_common_elems` sometimes missing for a text[] column - Mailing list pgsql-performance

From Frédéric Yhuel
Subject Re: Poor row estimates from planner, stat `most_common_elems` sometimes missing for a text[] column
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Msg-id 95e298e6-fdeb-4687-97cf-27942c1f0856@dalibo.com
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In response to Re: Poor row estimates from planner, stat `most_common_elems` sometimes missing for a text[] column  (Tom Lane <tgl@sss.pgh.pa.us>)
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On 6/5/25 23:52, Tom Lane wrote:
> The idea of treating lack of MCELEM differently from complete
> lack of stats still seems to have merit, though.


Couldn't we count / estimate the number of distinct two-by-two elements, 
and use that instead of the default selectivity estimate?

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