a8bb1a7779
When a join has an alias, the parser marks every Var referenced through that alias with the join's RT index as its syntactic referent (varnosyn), even though varno points at the underlying base relation. Since commit2ebf25e7d, join removal strips the removed relids from the query tree using ChangeVarNodes() with INVALID_VAR, which asserts that the relid doesn't appear in any field identifying a single relation. A varnosyn that names the removed join violates that, so a query like SELECT j.x FROM (t1 s(x) LEFT JOIN t2 ON s.x = t2.a) j; with t2.a unique fails an assertion. In non-assert builds, varnosyn is silently set to INVALID_VAR. Such syntactic references are still valid after the removal: the join is only taken out of the jointree, and its RTE remains in the rangetable through to the finished plan. So, when deleting a relid, leave varnosyn unchanged, as join removal did before2ebf25e7d. Back-patch to v16, as with commit2ebf25e7d. Author: Richard Guo <guofenglinux@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/CAMbWs484SQSdzWTgZYKvwtuC6J4m7acw0LfBjp3aWPvav7gC_w@mail.gmail.com Backpatch-through: 16
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/.