diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index e1fe4fec57..546213fa93 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -24353,6 +24353,12 @@ SELECT collation for ('foo' COLLATE "de_DE");
SHOW ALL commands.
+
+ NO_RESET
+ Parameters with this flag do not support
+ RESET commands.
+
+
NO_RESET_ALL
Parameters with this flag are excluded from
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index 8c2e08fad6..29ec6d886c 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -3243,6 +3243,26 @@ set_config_option_ext(const char *name, const char *value,
}
}
+ /* Disallow resetting and saving GUC_NO_RESET values */
+ if (record->flags & GUC_NO_RESET)
+ {
+ if (value == NULL)
+ {
+ ereport(elevel,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("parameter \"%s\" cannot be reset", name)));
+ return 0;
+ }
+ if (action == GUC_ACTION_SAVE)
+ {
+ ereport(elevel,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("parameter \"%s\" cannot be set temporarily or locally in functions",
+ name)));
+ return 0;
+ }
+ }
+
/*
* Should we set reset/stacked values? (If so, the behavior is not
* transactional.) This is done either when we get a default value from
diff --git a/src/backend/utils/misc/guc_funcs.c b/src/backend/utils/misc/guc_funcs.c
index 3d2df18659..ffc71726f9 100644
--- a/src/backend/utils/misc/guc_funcs.c
+++ b/src/backend/utils/misc/guc_funcs.c
@@ -141,9 +141,6 @@ ExecSetVariableStmt(VariableSetStmt *stmt, bool isTopLevel)
WarnNoTransactionBlock(isTopLevel, "SET LOCAL");
/* fall through */
case VAR_RESET:
- if (strcmp(stmt->name, "transaction_isolation") == 0)
- WarnNoTransactionBlock(isTopLevel, "RESET TRANSACTION");
-
(void) set_config_option(stmt->name,
NULL,
(superuser() ? PGC_SUSET : PGC_USERSET),
@@ -539,7 +536,7 @@ ShowAllGUCConfig(DestReceiver *dest)
Datum
pg_settings_get_flags(PG_FUNCTION_ARGS)
{
-#define MAX_GUC_FLAGS 5
+#define MAX_GUC_FLAGS 6
char *varname = TextDatumGetCString(PG_GETARG_DATUM(0));
struct config_generic *record;
int cnt = 0;
@@ -554,6 +551,8 @@ pg_settings_get_flags(PG_FUNCTION_ARGS)
if (record->flags & GUC_EXPLAIN)
flags[cnt++] = CStringGetTextDatum("EXPLAIN");
+ if (record->flags & GUC_NO_RESET)
+ flags[cnt++] = CStringGetTextDatum("NO_RESET");
if (record->flags & GUC_NO_RESET_ALL)
flags[cnt++] = CStringGetTextDatum("NO_RESET_ALL");
if (record->flags & GUC_NO_SHOW_ALL)
diff --git a/src/backend/utils/misc/guc_tables.c b/src/backend/utils/misc/guc_tables.c
index ab3140ff3a..fda3f9befb 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,
diff --git a/src/include/utils/guc.h b/src/include/utils/guc.h
index e426dd757d..a846500bc5 100644
--- a/src/include/utils/guc.h
+++ b/src/include/utils/guc.h
@@ -238,6 +238,8 @@ typedef enum
*/
#define GUC_RUNTIME_COMPUTED 0x200000
+#define GUC_NO_RESET 0x400000 /* not support RESET and save */
+
#define GUC_UNIT (GUC_UNIT_MEMORY | GUC_UNIT_TIME)
diff --git a/src/pl/plpgsql/src/expected/plpgsql_transaction.out b/src/pl/plpgsql/src/expected/plpgsql_transaction.out
index 254e5b7a70..adff10fa6d 100644
--- a/src/pl/plpgsql/src/expected/plpgsql_transaction.out
+++ b/src/pl/plpgsql/src/expected/plpgsql_transaction.out
@@ -576,8 +576,7 @@ BEGIN
PERFORM 1;
RAISE INFO '%', current_setting('transaction_isolation');
COMMIT;
- SET TRANSACTION ISOLATION LEVEL REPEATABLE READ;
- RESET TRANSACTION ISOLATION LEVEL;
+ SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
PERFORM 1;
RAISE INFO '%', current_setting('transaction_isolation');
COMMIT;
@@ -585,7 +584,7 @@ END;
$$;
INFO: read committed
INFO: repeatable read
-INFO: read committed
+INFO: serializable
-- error cases
DO LANGUAGE plpgsql $$
BEGIN
diff --git a/src/pl/plpgsql/src/sql/plpgsql_transaction.sql b/src/pl/plpgsql/src/sql/plpgsql_transaction.sql
index 8d76d00daa..c73fca7e03 100644
--- a/src/pl/plpgsql/src/sql/plpgsql_transaction.sql
+++ b/src/pl/plpgsql/src/sql/plpgsql_transaction.sql
@@ -481,8 +481,7 @@ BEGIN
PERFORM 1;
RAISE INFO '%', current_setting('transaction_isolation');
COMMIT;
- SET TRANSACTION ISOLATION LEVEL REPEATABLE READ;
- RESET TRANSACTION ISOLATION LEVEL;
+ SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;
PERFORM 1;
RAISE INFO '%', current_setting('transaction_isolation');
COMMIT;
diff --git a/src/test/regress/expected/guc.out b/src/test/regress/expected/guc.out
index 3de6404ba5..2914b950b4 100644
--- a/src/test/regress/expected/guc.out
+++ b/src/test/regress/expected/guc.out
@@ -839,6 +839,7 @@ SELECT pg_settings_get_flags('does_not_exist');
CREATE TABLE tab_settings_flags AS SELECT name, category,
'EXPLAIN' = ANY(flags) AS explain,
+ 'NO_RESET' = ANY(flags) AS no_reset,
'NO_RESET_ALL' = ANY(flags) AS no_reset_all,
'NO_SHOW_ALL' = ANY(flags) AS no_show_all,
'NOT_IN_SAMPLE' = ANY(flags) AS not_in_sample,
@@ -906,4 +907,12 @@ SELECT name FROM tab_settings_flags
------
(0 rows)
+-- NO_RESET implies NO_RESET_ALL.
+SELECT name FROM tab_settings_flags
+ WHERE no_reset AND NOT no_reset_all
+ ORDER BY 1;
+ name
+------
+(0 rows)
+
DROP TABLE tab_settings_flags;
diff --git a/src/test/regress/expected/transactions.out b/src/test/regress/expected/transactions.out
index a46fa5d48a..9351d1d134 100644
--- a/src/test/regress/expected/transactions.out
+++ b/src/test/regress/expected/transactions.out
@@ -44,6 +44,40 @@ SELECT * FROM xacttest;
777 | 777.777
(5 rows)
+-- Test that transaction characteristics cannot be reset.
+BEGIN TRANSACTION ISOLATION LEVEL SERIALIZABLE;
+SELECT COUNT(*) FROM xacttest;
+ count
+-------
+ 5
+(1 row)
+
+RESET transaction_isolation; -- error
+ERROR: parameter "transaction_isolation" cannot be reset
+END;
+BEGIN TRANSACTION READ ONLY;
+SELECT COUNT(*) FROM xacttest;
+ count
+-------
+ 5
+(1 row)
+
+RESET transaction_read_only; -- error
+ERROR: parameter "transaction_read_only" cannot be reset
+END;
+BEGIN TRANSACTION DEFERRABLE;
+SELECT COUNT(*) FROM xacttest;
+ count
+-------
+ 5
+(1 row)
+
+RESET transaction_deferrable; -- error
+ERROR: parameter "transaction_deferrable" cannot be reset
+END;
+CREATE FUNCTION errfunc() RETURNS int LANGUAGE SQL AS 'SELECT 1'
+SET transaction_read_only = on; -- error
+ERROR: parameter "transaction_read_only" cannot be set temporarily or locally in functions
-- Read-only tests
CREATE TABLE writetest (a int);
CREATE TEMPORARY TABLE temptest (a int);
diff --git a/src/test/regress/sql/guc.sql b/src/test/regress/sql/guc.sql
index d5db101e48..d40d0c178f 100644
--- a/src/test/regress/sql/guc.sql
+++ b/src/test/regress/sql/guc.sql
@@ -324,6 +324,7 @@ SELECT pg_settings_get_flags(NULL);
SELECT pg_settings_get_flags('does_not_exist');
CREATE TABLE tab_settings_flags AS SELECT name, category,
'EXPLAIN' = ANY(flags) AS explain,
+ 'NO_RESET' = ANY(flags) AS no_reset,
'NO_RESET_ALL' = ANY(flags) AS no_reset_all,
'NO_SHOW_ALL' = ANY(flags) AS no_show_all,
'NOT_IN_SAMPLE' = ANY(flags) AS not_in_sample,
@@ -360,4 +361,8 @@ SELECT name FROM tab_settings_flags
SELECT name FROM tab_settings_flags
WHERE no_show_all AND NOT not_in_sample
ORDER BY 1;
+-- NO_RESET implies NO_RESET_ALL.
+SELECT name FROM tab_settings_flags
+ WHERE no_reset AND NOT no_reset_all
+ ORDER BY 1;
DROP TABLE tab_settings_flags;
diff --git a/src/test/regress/sql/transactions.sql b/src/test/regress/sql/transactions.sql
index d71c3ce93e..7ee5f6aaa5 100644
--- a/src/test/regress/sql/transactions.sql
+++ b/src/test/regress/sql/transactions.sql
@@ -35,6 +35,24 @@ SELECT oid FROM pg_class WHERE relname = 'disappear';
-- should have members again
SELECT * FROM xacttest;
+-- Test that transaction characteristics cannot be reset.
+BEGIN TRANSACTION ISOLATION LEVEL SERIALIZABLE;
+SELECT COUNT(*) FROM xacttest;
+RESET transaction_isolation; -- error
+END;
+
+BEGIN TRANSACTION READ ONLY;
+SELECT COUNT(*) FROM xacttest;
+RESET transaction_read_only; -- error
+END;
+
+BEGIN TRANSACTION DEFERRABLE;
+SELECT COUNT(*) FROM xacttest;
+RESET transaction_deferrable; -- error
+END;
+
+CREATE FUNCTION errfunc() RETURNS int LANGUAGE SQL AS 'SELECT 1'
+SET transaction_read_only = on; -- error
-- Read-only tests