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Previously, CHECK constraints of the same scope were checked in whatever order they happened to be read from pg_constraint. (Usually, but not reliably, this would be creation order for domain constraints and reverse creation order for table constraints, because of differing implementation details.) Nondeterministic results of this sort are problematic at least for testing purposes, and in discussion it was agreed to be a violation of the principle of least astonishment. Therefore, borrow the principle already established for triggers, and apply such checks in name order (using strcmp() sort rules). This lets users control the check order if they have a mind to. Domain CHECK constraints still follow the rule of checking lower nested domains' constraints first; the name sort only applies to multiple constraints attached to the same domain. In passing, I failed to resist the temptation to wordsmith a bit in create_domain.sgml. Apply to HEAD only, since this could result in a behavioral change in existing applications, and the potential regression test failures have not actually been observed in our buildfarm.
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: http://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 http://www.postgresql.org/download/. For more information look at our web site located at http://www.postgresql.org/.