postgresql/src/bin/scripts
Andres Freund c66a7d75e6 Handle DROP DATABASE getting interrupted
Until now, when DROP DATABASE got interrupted in the wrong moment, the removal
of the pg_database row would also roll back, even though some irreversible
steps have already been taken. E.g. DropDatabaseBuffers() might have thrown
out dirty buffers, or files could have been unlinked. But we continued to
allow connections to such a corrupted database.

To fix this, mark databases invalid with an in-place update, just before
starting to perform irreversible steps. As we can't add a new column in the
back branches, we use pg_database.datconnlimit = -2 for this purpose.

An invalid database cannot be connected to anymore, but can still be
dropped.

Unfortunately we can't easily add output to psql's \l to indicate that some
database is invalid, it doesn't fit in any of the existing columns.

Add tests verifying that a interrupted DROP DATABASE is handled correctly in
the backend and in various tools.

Reported-by: Evgeny Morozov <postgresql3@realityexists.net>
Author: Andres Freund <andres@anarazel.de>
Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Reviewed-by: Thomas Munro <thomas.munro@gmail.com>
Discussion: https://postgr.es/m/20230509004637.cgvmfwrbht7xm7p6@awork3.anarazel.de
Discussion: https://postgr.es/m/20230314174521.74jl6ffqsee5mtug@awork3.anarazel.de
Backpatch: 11-, bug present in all supported versions
2023-07-13 13:03:28 -07:00
..
po Translation updates 2023-06-26 12:02:02 +02:00
t Handle DROP DATABASE getting interrupted 2023-07-13 13:03:28 -07:00
.gitignore Remove createlang and droplang 2017-03-23 14:16:45 -04:00
clusterdb.c Handle DROP DATABASE getting interrupted 2023-07-13 13:03:28 -07:00
common.c Update copyright for 2023 2023-01-02 15:00:37 -05:00
common.h Update copyright for 2023 2023-01-02 15:00:37 -05:00
createdb.c CREATE DATABASE: make LOCALE apply to all collation providers. 2023-06-16 10:27:32 -07:00
createuser.c Document deprecated createuser option. 2023-05-23 19:35:05 -07:00
dropdb.c Update copyright for 2023 2023-01-02 15:00:37 -05:00
dropuser.c Update copyright for 2023 2023-01-02 15:00:37 -05:00
Makefile Update copyright for 2023 2023-01-02 15:00:37 -05:00
meson.build Update copyright for 2023 2023-01-02 15:00:37 -05:00
nls.mk Break up long GETTEXT_FILES lists 2023-03-08 15:05:43 +01:00
pg_isready.c Update copyright for 2023 2023-01-02 15:00:37 -05:00
reindexdb.c Handle DROP DATABASE getting interrupted 2023-07-13 13:03:28 -07:00
vacuumdb.c Handle DROP DATABASE getting interrupted 2023-07-13 13:03:28 -07:00