While heapam reproduces the insertion order of rows well, updates can move rows to varying places depending on autovacuum activity. In most regression tests we've guarded against getting variable results due to that, but float4.sql and float8.sql had escaped notice so far because they update tables that are too small for autovacuum to pay attention to. With increasing interest in non-heap table AMs, it seems worth allowing for update behaviors that are not like heapam's. Hence, add ORDER BY to stabilize the results in case the updates put the rows in a different order. (We'll continue to assume that a seqscan will reproduce original insertion order, though. Removing that assumption would require vastly-more-invasive test changes.) Author: Pavel Borisov <pashkin.elfe@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/CALT9ZEExHAnBoBVQzQuWPMKUbapF5-FBO3fdeYG3s2tuWQz1NQ@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/.