diff options
| author | Tom Lane | 2022-09-27 15:47:12 +0000 |
|---|---|---|
| committer | Tom Lane | 2022-09-27 15:47:12 +0000 |
| commit | 385366426511399a91da327c0f04765bbcfd5322 (patch) | |
| tree | bb6851d6157032806a9df6ab23a4242b548bb378 /src/backend/utils/misc/guc_tables.c | |
| parent | 4148c8b3daf95ca308f055e103f6ee82e25b8f99 (diff) | |
Introduce GUC_NO_RESET flag.
Previously, the transaction-property GUCs such as transaction_isolation
could be reset after starting a transaction, because we marked them
as GUC_NO_RESET_ALL but still allowed a targeted RESET. That leads to
assertion failures or worse, because those properties aren't supposed
to change after we've acquired a transaction snapshot.
There are some NO_RESET_ALL variables for which RESET is okay, so
we can't just redefine the semantics of that flag. Instead introduce
a separate GUC_NO_RESET flag. Mark "seed", as well as the transaction
property GUCs, as GUC_NO_RESET.
We have to disallow GUC_ACTION_SAVE as well as straight RESET, because
otherwise a function having a "SET transaction_isolation" clause can
still break things: the end-of-function restore action is equivalent
to a RESET.
No back-patch, as it's conceivable that someone is doing something
this patch will forbid (like resetting one of these GUCs at transaction
start, or "CREATE FUNCTION ... SET transaction_read_only = 1") and not
running into problems with it today. Given how long we've had this
issue and not noticed, the side effects in non-assert builds can't be
too serious.
Per bug #17385 from Andrew Bille.
Masahiko Sawada
Discussion: https://postgr.es/m/[email protected]
Diffstat (limited to 'src/backend/utils/misc/guc_tables.c')
| -rw-r--r-- | src/backend/utils/misc/guc_tables.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/src/backend/utils/misc/guc_tables.c b/src/backend/utils/misc/guc_tables.c index ab3140ff3af..fda3f9befb0 100644 --- a/src/backend/utils/misc/guc_tables.c +++ b/src/backend/utils/misc/guc_tables.c @@ -1505,7 +1505,7 @@ struct config_bool ConfigureNamesBool[] = {"transaction_read_only", PGC_USERSET, CLIENT_CONN_STATEMENT, gettext_noop("Sets the current transaction's read-only status."), NULL, - GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE + GUC_NO_RESET | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE }, &XactReadOnly, false, @@ -1524,7 +1524,7 @@ struct config_bool ConfigureNamesBool[] = {"transaction_deferrable", PGC_USERSET, CLIENT_CONN_STATEMENT, gettext_noop("Whether to defer a read-only serializable transaction until it can be executed with no possible serialization failures."), NULL, - GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE + GUC_NO_RESET | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE }, &XactDeferrable, false, @@ -3606,7 +3606,7 @@ struct config_real ConfigureNamesReal[] = {"seed", PGC_USERSET, UNGROUPED, gettext_noop("Sets the seed for random-number generation."), NULL, - GUC_NO_SHOW_ALL | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE + GUC_NO_SHOW_ALL | GUC_NO_RESET | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE }, &phony_random_seed, 0.0, -1.0, 1.0, @@ -4557,7 +4557,7 @@ struct config_enum ConfigureNamesEnum[] = {"transaction_isolation", PGC_USERSET, CLIENT_CONN_STATEMENT, gettext_noop("Sets the current transaction's isolation level."), NULL, - GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE + GUC_NO_RESET | GUC_NO_RESET_ALL | GUC_NOT_IN_SAMPLE | GUC_DISALLOW_IN_FILE }, &XactIsoLevel, XACT_READ_COMMITTED, isolation_level_options, |