b9bffa004a
We've noted certain EXPLAIN queries on these tables occasionally showing unexpected plan choices. This seems to happen because VACUUM sometimes fails to update relpages/reltuples for one of these single-page tables, due to bgwriter or checkpointer holding a pin on the lone page at just the wrong time. To ensure those values get set, insert explicit ANALYZE operations on these tables after we finish populating them. This doesn't seem to affect any other test cases, so it's a usable fix. Back-patch to v12. In principle the issue exists further back, but we have not seen it before v12, so I won't risk back-patching further. Discussion: https://postgr.es/m/24480.1569518042@sss.pgh.pa.us
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/.