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
PostgreSQL Database Management System
This directory contains the source code distribution of the PostgreSQL database management system.
PostgreSQL is an advanced object-relational database management system that supports an extended subset of the SQL standard, including transactions, foreign keys, subqueries, triggers, user-defined types and functions. This distribution also contains C language bindings.
Copyright and license information can be found in the file COPYRIGHT.
General documentation about this version of PostgreSQL can be found at https://www.postgresql.org/docs/devel/. In particular, information about building PostgreSQL from the source code can be found at https://www.postgresql.org/docs/devel/installation.html.
The latest version of this software, and related software, may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.