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contain_mutable_functions and contain_volatile_functions give reliable answers only after expression preprocessing (specifically eval_const_expressions). Some places understand this, but some did not get the memo --- which is not entirely their fault, because the problem is documented only in places far away from those functions. Introduce wrapper functions that allow doing the right thing easily, and add commentary in hopes of preventing future mistakes from copy-and-paste of code that's only conditionally safe. Two actual bugs of this ilk are fixed here. We failed to preprocess column GENERATED expressions before checking mutability, so that the code could fail to detect the use of a volatile function default-argument expression, or it could reject a polymorphic function that is actually immutable on the datatype of interest. Likewise, column DEFAULT expressions weren't preprocessed before determining if it's safe to apply the attmissingval mechanism. A false negative would just result in an unnecessary table rewrite, but a false positive could allow the attmissingval mechanism to be used in a case where it should not be, resulting in unexpected initial values in a new column. In passing, re-order the steps in ComputePartitionAttrs so that its checks for invalid column references are done before applying expression_planner, rather than after. The previous coding would not complain if a partition expression contains a disallowed column reference that gets optimized away by constant folding, which seems to me to be a behavior we do not want. Per bug #18097 from Jim Keener. Back-patch to all supported versions. Discussion: https://postgr.es/m/18097-ebb179674f22932f@postgresql.org
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/.