6 files changed, 60 insertions, 27 deletions
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index d10cc28b0c1..e617381bf40 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -57,6 +57,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	202305121
+#define CATALOG_VERSION_NO	202305171
 
 #endif
diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat
index b2bc81b15f8..d7a60b39b58 100644
--- a/src/include/catalog/pg_proc.dat
+++ b/src/include/catalog/pg_proc.dat
@@ -1505,38 +1505,12 @@
 { oid => '745', descr => 'current user name',
   proname => 'current_user', provolatile => 's', prorettype => 'name',
   proargtypes => '', prosrc => 'current_user' },
-{ oid => '9695', descr => 'current role name',
-  proname => 'current_role', provolatile => 's', prorettype => 'name',
-  proargtypes => '', prosrc => 'current_user' },
-{ oid => '9696', descr => 'user name',
-  proname => 'user', provolatile => 's', prorettype => 'name',
-  proargtypes => '', prosrc => 'current_user' },
-{ oid => '9697', descr => 'name of the current database',
-  proname => 'current_catalog', provolatile => 's', prorettype => 'name',
-  proargtypes => '', prosrc => 'current_database' },
 { oid => '746', descr => 'session user name',
   proname => 'session_user', provolatile => 's', prorettype => 'name',
   proargtypes => '', prosrc => 'session_user' },
 { oid => '9977', descr => 'system user name',
   proname => 'system_user', provolatile => 's', prorettype => 'text',
   proargtypes => '', prosrc => 'system_user' },
-{ oid => '9978', descr => 'current date',
-  proname => 'current_date', provolatile => 's', prorettype => 'date',
-  proargtypes => '', prosrc => 'current_date' },
-{ oid => '9979', descr => 'current time',
-  proname => 'current_time', proisstrict => 'f', provolatile => 's',
-  prorettype => 'timetz', proargtypes => 'int4', prosrc => 'current_time' },
-{ oid => '9980', descr => 'current timestamp',
-  proname => 'current_timestamp', proisstrict => 'f', provolatile => 's',
-  prorettype => 'timestamptz', proargtypes => 'int4',
-  prosrc => 'current_timestamp' },
-{ oid => '9981', descr => 'local time',
-  proname => 'localtime', proisstrict => 'f', provolatile => 's',
-  prorettype => 'time', proargtypes => 'int4', prosrc => 'sql_localtime' },
-{ oid => '9982', descr => 'local timestamp',
-  proname => 'localtimestamp', proisstrict => 'f', provolatile => 's',
-  prorettype => 'timestamp', proargtypes => 'int4',
-  prosrc => 'sql_localtimestamp' },
 
 { oid => '744',
   proname => 'array_eq', prorettype => 'bool',
diff --git a/src/include/executor/execExpr.h b/src/include/executor/execExpr.h
index 157b0d85f29..048573c2bcb 100644
--- a/src/include/executor/execExpr.h
+++ b/src/include/executor/execExpr.h
@@ -171,6 +171,7 @@ typedef enum ExprEvalOp
 	EEOP_DISTINCT,
 	EEOP_NOT_DISTINCT,
 	EEOP_NULLIF,
+	EEOP_SQLVALUEFUNCTION,
 	EEOP_CURRENTOFEXPR,
 	EEOP_NEXTVALUEEXPR,
 	EEOP_ARRAYEXPR,
@@ -418,6 +419,12 @@ typedef struct ExprEvalStep
 			FunctionCallInfo fcinfo_data_in;
 		}			iocoerce;
 
+		/* for EEOP_SQLVALUEFUNCTION */
+		struct
+		{
+			SQLValueFunction *svf;
+		}			sqlvaluefunction;
+
 		/* for EEOP_NEXTVALUEEXPR */
 		struct
 		{
@@ -769,6 +776,7 @@ extern void ExecEvalParamExec(ExprState *state, ExprEvalStep *op,
 							  ExprContext *econtext);
 extern void ExecEvalParamExtern(ExprState *state, ExprEvalStep *op,
 								ExprContext *econtext);
+extern void ExecEvalSQLValueFunction(ExprState *state, ExprEvalStep *op);
 extern void ExecEvalCurrentOfExpr(ExprState *state, ExprEvalStep *op);
 extern void ExecEvalNextValueExpr(ExprState *state, ExprEvalStep *op);
 extern void ExecEvalRowNull(ExprState *state, ExprEvalStep *op,
diff --git a/src/include/nodes/primnodes.h b/src/include/nodes/primnodes.h
index be9c29f0bfb..08e7dae73f1 100644
--- a/src/include/nodes/primnodes.h
+++ b/src/include/nodes/primnodes.h
@@ -1446,6 +1446,49 @@ typedef struct MinMaxExpr
 } MinMaxExpr;
 
 /*
+ * SQLValueFunction - parameterless functions with special grammar productions
+ *
+ * The SQL standard categorizes some of these as <datetime value function>
+ * and others as <general value specification>.  We call 'em SQLValueFunctions
+ * for lack of a better term.  We store type and typmod of the result so that
+ * some code doesn't need to know each function individually, and because
+ * we would need to store typmod anyway for some of the datetime functions.
+ * Note that currently, all variants return non-collating datatypes, so we do
+ * not need a collation field; also, all these functions are stable.
+ */
+typedef enum SQLValueFunctionOp
+{
+	SVFOP_CURRENT_DATE,
+	SVFOP_CURRENT_TIME,
+	SVFOP_CURRENT_TIME_N,
+	SVFOP_CURRENT_TIMESTAMP,
+	SVFOP_CURRENT_TIMESTAMP_N,
+	SVFOP_LOCALTIME,
+	SVFOP_LOCALTIME_N,
+	SVFOP_LOCALTIMESTAMP,
+	SVFOP_LOCALTIMESTAMP_N,
+	SVFOP_CURRENT_ROLE,
+	SVFOP_CURRENT_USER,
+	SVFOP_USER,
+	SVFOP_SESSION_USER,
+	SVFOP_CURRENT_CATALOG,
+	SVFOP_CURRENT_SCHEMA
+} SQLValueFunctionOp;
+
+typedef struct SQLValueFunction
+{
+	Expr		xpr;
+	SQLValueFunctionOp op;		/* which function this is */
+	/*
+	 * Result type/typmod.  Type is fully determined by "op", so no need to
+	 * include this Oid in the query jumbling.
+	 */
+	Oid			type pg_node_attr(query_jumble_ignore);
+	int32		typmod;
+	int			location;		/* token location, or -1 if unknown */
+} SQLValueFunction;
+
+/*
  * XmlExpr - various SQL/XML functions requiring special grammar productions
  *
  * 'name' carries the "NAME foo" argument (already XML-escaped).
diff --git a/src/include/utils/date.h b/src/include/utils/date.h
index 5fd886b3dba..97e1a021217 100644
--- a/src/include/utils/date.h
+++ b/src/include/utils/date.h
@@ -96,6 +96,7 @@ TimeTzADTPGetDatum(const TimeTzADT *X)
 
 
 /* date.c */
+extern int32 anytime_typmod_check(bool istz, int32 typmod);
 extern double date2timestamp_no_overflow(DateADT dateVal);
 extern Timestamp date2timestamp_opt_overflow(DateADT dateVal, int *overflow);
 extern TimestampTz date2timestamptz_opt_overflow(DateADT dateVal, int *overflow);
@@ -103,6 +104,9 @@ extern int32 date_cmp_timestamp_internal(DateADT dateVal, Timestamp dt2);
 extern int32 date_cmp_timestamptz_internal(DateADT dateVal, TimestampTz dt2);
 
 extern void EncodeSpecialDate(DateADT dt, char *str);
+extern DateADT GetSQLCurrentDate(void);
+extern TimeTzADT *GetSQLCurrentTime(int32 typmod);
+extern TimeADT GetSQLLocalTime(int32 typmod);
 extern int	time2tm(TimeADT time, struct pg_tm *tm, fsec_t *fsec);
 extern int	timetz2tm(TimeTzADT *time, struct pg_tm *tm, fsec_t *fsec, int *tzp);
 extern int	tm2time(struct pg_tm *tm, fsec_t fsec, TimeADT *result);
diff --git a/src/include/utils/timestamp.h b/src/include/utils/timestamp.h
index edd59dc4322..c4dd96c8c97 100644
--- a/src/include/utils/timestamp.h
+++ b/src/include/utils/timestamp.h
@@ -95,7 +95,11 @@ extern PGDLLIMPORT TimestampTz PgReloadTime;
 
 /* Internal routines (not fmgr-callable) */
 
+extern int32 anytimestamp_typmod_check(bool istz, int32 typmod);
+
 extern TimestampTz GetCurrentTimestamp(void);
+extern TimestampTz GetSQLCurrentTimestamp(int32 typmod);
+extern Timestamp GetSQLLocalTimestamp(int32 typmod);
 extern void TimestampDifference(TimestampTz start_time, TimestampTz stop_time,
 								long *secs, int *microsecs);
 extern long TimestampDifferenceMilliseconds(TimestampTz start_time,