8ca22ee11c
before it checks whether the expression is immutable. This covers two cases that were previously handled poorly: 1. SQL function inlining could reduce the apparent volatility of the expression, allowing an expression to be accepted where it previously would not have been. As an example, polymorphic functions must be marked with the worst-case volatility they have for any argument type, but for specific argument types they might not be so volatile, so indexing could be allowed. (Since the planner will refuse to inline functions in cases where the apparent volatility of the expression would increase, this won't break any cases that were accepted before.) 2. A nominally immutable function could have default arguments that are volatile expressions. In such a case insertion of the defaults will increase both the apparent and actual volatility of the expression, so it is *necessary* to check this before allowing the expression to be indexed. Back-patch to 8.4, where default arguments were introduced.
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. Changes between all PostgreSQL releases are recorded in the file HISTORY. 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/.