pgsql: Doc: clarify n_distinct_inherited setting - Mailing list pgsql-committers

From David Rowley
Subject pgsql: Doc: clarify n_distinct_inherited setting
Date
Msg-id E1v8P78-001XZ5-1P@gemulon.postgresql.org
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List pgsql-committers
Doc: clarify n_distinct_inherited setting

There was some confusion around how to adjust the n_distinct estimates
for partitioned tables.  Here we try and clarify that
n_distinct_inherited needs to be adjusted rather than n_distinct.

Also fix some slightly misleading text which was talking about table
size rather than table rows, fix a grammatical error, and adjust some
text which indicated that ANALYZE was performing calculations based on
the n_distinct settings.  Really it's the query planner that does this
and ANALYZE only stores the overridden n_distinct estimate value in
pg_statistic.

Author: David Rowley <dgrowleyml@gmail.com>
Reviewed-by: David G. Johnston <david.g.johnston@gmail.com>
Reviewed-by: Chao Li <li.evan.chao@gmail.com>
Backpatch-through: 13
Discussion: https://postgr.es/m/CAApHDvrL7a-ZytM1SP8Uk9nEw9bR2CPzVb+uP+bcNj=_q-ZmVw@mail.gmail.com

Branch
------
REL_18_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/f691e72585a3811a05e37d27e898b1d816ff9ff9

Modified Files
--------------
doc/src/sgml/ref/alter_table.sgml | 34 ++++++++++++++++------------------
1 file changed, 16 insertions(+), 18 deletions(-)


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