Thread: [COMMITTERS] pgsql: Use a blacklist to distinguish original from add-on enumvalues.
[COMMITTERS] pgsql: Use a blacklist to distinguish original from add-on enumvalues.
From
Tom Lane
Date:
Use a blacklist to distinguish original from add-on enum values. Commit 15bc038f9 allowed ALTER TYPE ADD VALUE to be executed inside transaction blocks, by disallowing the use of the added value later in the same transaction, except under limited circumstances. However, the test for "limited circumstances" was heuristic and could reject references to enum values that were created during CREATE TYPE AS ENUM, not just later. This breaks the use-case of restoring pg_dump scripts in a single transaction, as reported in bug #14825 from Balazs Szilfai. We can improve this by keeping a "blacklist" table of enum value OIDs created by ALTER TYPE ADD VALUE during the current transaction. Any visible-but-uncommitted value whose OID is not in the blacklist must have been created by CREATE TYPE AS ENUM, and can be used safely because it could not have a lifespan shorter than its parent enum type. This change also removes the restriction that a renamed enum value can't be used before being committed (unless it was on the blacklist). Andrew Dunstan, with cosmetic improvements by me. Back-patch to v10. Discussion: https://postgr.es/m/20170922185904.1448.16585@wrigleys.postgresql.org Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/1635e80d30b16df98aebead12f2b82f17efd9bc8 Modified Files -------------- doc/src/sgml/ref/alter_type.sgml | 2 -- src/backend/access/transam/xact.c | 4 +++ src/backend/catalog/pg_enum.c | 64 ++++++++++++++++++++++++++++++++++++++ src/backend/utils/adt/enum.c | 9 ++++++ src/include/catalog/pg_enum.h | 2 ++ src/test/regress/expected/enum.out | 21 +++++++++++++ src/test/regress/sql/enum.sql | 13 ++++++++ 7 files changed, 113 insertions(+), 2 deletions(-) -- Sent via pgsql-committers mailing list (pgsql-committers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-committers