The tablesample and securityQuals subtrees of a RangeTblEntry can
include Vars, which will cause trouble if they point at a removed
rel and are visited during later processing. Hence, clear those
fields during join removal, as we already do for the subquery field.
remove_useless_outer_joins got this right for securityQuals but
not tablesample, while remove_self_join_rel missed doing it for
securityQuals. (It escapes trouble for tablesample only because we
made a policy decision to never touch sampled relations for SJE.)
Oversight in 2ebf25e7d. Back-patch to v16, like that commit
(but the SJE issue only goes as far back as v18).
Author: shihao zhong <zhong950419@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/CAGRkXqSOAT1yop44B8jwacL_91rxK=QuoU8Of3NLMb9NgAO2NA@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.
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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.
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