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Plan weirdness. A sort produces more rows than the node beneath it - Mailing list pgsql-performance

From Dane Foster
Subject Plan weirdness. A sort produces more rows than the node beneath it
Date
Msg-id CA+WxinKHxRUgDwbUfsKNiq5MXn8kRFayo0KqZzTmxXG93BbK4g@mail.gmail.com
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Responses Re: Plan weirdness. A sort produces more rows than the node beneath it  (Jeff Janes <jeff.janes@gmail.com>)
Re: Plan weirdness. A sort produces more rows than the node beneath it  (Tom Lane <tgl@sss.pgh.pa.us>)
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Hello,

I'm trying to understand a bit of weirdness in a plan output. There is a sort node above a sequential scan node where the scan node produces 26,026 rows yet the sort node above it produces 42,995,408. How is it possible to sort more data than you received?

https://explain.dalibo.com/plan/1ee665h69f92chc5

The PostgreSQL version is 14.2 running on Amazon's RDS. Thanks.


Dane

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