f862d57057
We assume that direct-modify ForeignScan nodes cannot be re-evaluated during EvalPlanQual processing, but the rework for inherited UPDATE/DELETE in commit 86dc90056 changed things, without considering that, so that such ForeignScan nodes get called as part of the EvalPlanQual subtree during EvalPlanQual processing in the case of an inherited UPDATE/DELETE where the inheritance set contains foreign target relations. To avoid re-evaluating such ForeignScan nodes during EvalPlanQual processing, commit c3928b467 modified nodeForeignscan.c, but the assumption made there that ExecForeignScan() should never be called for such ForeignScan nodes during EvalPlanQual processing turned out to be wrong in some cases, leading to a segmentation fault or a "cannot re-evaluate a Foreign Update or Delete during EvalPlanQual" error. Fix by modifying nodeForeignscan.c further to avoid re-evaluating such ForeignScan nodes even in ExecForeignScan()/ExecReScanForeignScan() during EvalPlanQual processing. Since this makes non-reachable the test-and-elog added to ForeignNext() by commit c3928b467 that produced the aforesaid error, convert the test-and-elog to an Assert. Per bug #17355 from Alexander Lakhin. Back-patch to v14 where both commits came in. Patch by me, reviewed and tested by Alexander Lakhin and Amit Langote. Discussion: https://postgr.es/m/17355-de8e362eb7001a96@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/.