5278668d7a
transformTableLikeClause believed that it could process extended statistics immediately because "the representation of CreateStatsStmt doesn't depend on column numbers". That was true when extended stats were first introduced, but it was falsified by the addition of extended stats on expressions: the parsed expression tree is fed forward by the LIKE option, and that will contain Vars. So if the new table doesn't have attnums identical to the old one's (typically because there are some dropped columns in the old one), that doesn't work. The CREATE goes through, but it emits invalid statistics objects that will cause problems later. Fortunately, we already have logic that can adapt expression trees to the possibly-new column numbering. To use it, we have to delay processing of CREATE_TABLE_LIKE_STATISTICS into expandTableLikeClause, just as for other LIKE options that involve expressions. Per bug #18468 from Alexander Lakhin. Back-patch to v14 where extended statistics on expressions were added. Discussion: https://postgr.es/m/18468-f5add190e3fa5902@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.
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/.