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From: Patrick BUNINO <taijiquan@neuronnexion.fr>
To: pgsql-www@postgresql.org
Subject: Wiki Editor request
Date: Wed, 01 Oct 2025 14:41:26 +0200
Message-ID: <20251001144126.14211k10ws970dx2@monmail.nnx.com> (raw)

Hi .
I’ve just created an account as Patrick83300.

The Count_Estimate Wiki Page seems wrong and i’d like to change few things :
The example create table has 1000 rows and not 100 :) ,  
generate_series(1,1000) makes 1000 numbers, not 100 (at least in  
Postgres 9.5.3)

One should use a «explain select ... where t<999999999999» in order to  
get the actual number of rows in the "rows=" part of the plan.
explain select * from tbl where t<2222;
QUERY PLAN
....... rows=1000
Filter: (t < 2222)

If one use t<100 he gets rows=100 which is not an estimation of the  
TOTAL number of rows in the table.

Cordialement.
Patrick BUNINO

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