3465c8a869
Previously the descriptions of tup_returned and tup_fetched columns
in pg_stat_database view were confusing. This commit improves them
so that they represent the following formulas of those columns
more accurately.
* pg_stat_database.tup_returned
= sum(pg_stat_all_tables.seq_tup_read)
+ sum(pg_stat_all_indexes.idx_tup_read)
* pg_stat_database.tup_fetched
= sum(pg_stat_all_tables.idx_tup_fetch)
In these formulas, note that the counters for some system catalogs
like pg_database shared across all databases of a cluster are excluded
from the calculations of sum.
Author: Masahiro Ikeda
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/9eeeccdb-5dd7-90f9-2807-a4b5d2b76ca3@oss.nttdata.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. PostgreSQL has many language interfaces, many of which are listed here: https://www.postgresql.org/download/ See the file INSTALL for instructions on how to build and install PostgreSQL. That file also lists supported operating systems and hardware platforms and contains information regarding any other software packages that are required to build or run the PostgreSQL system. Copyright and license information can be found in the file COPYRIGHT. A comprehensive documentation set is included in this distribution; it can be read as described in the installation instructions. The latest version of this software may be obtained at https://www.postgresql.org/download/. For more information look at our web site located at https://www.postgresql.org/.