SQL procedures

This adds a new object type "procedure" that is similar to a function
but does not have a return type and is invoked by the new CALL statement
instead of SELECT or similar.  This implementation is aligned with the
SQL standard and compatible with or similar to other SQL implementations.

This commit adds new commands CALL, CREATE/ALTER/DROP PROCEDURE, as well
as ALTER/DROP ROUTINE that can refer to either a function or a
procedure (or an aggregate function, as an extension to SQL).  There is
also support for procedures in various utility commands such as COMMENT
and GRANT, as well as support in pg_dump and psql.  Support for defining
procedures is available in all the languages supplied by the core
distribution.

While this commit is mainly syntax sugar around existing functionality,
future features will rely on having procedures as a separate object
type.

Reviewed-by: Andrew Dunstan <andrew.dunstan@2ndquadrant.com>

src/include/parser/kwlist.h

@@ -63,6 +63,7 @@ PG_KEYWORD("boolean", BOOLEAN_P, COL_NAME_KEYWORD)
 PG_KEYWORD("both", BOTH, RESERVED_KEYWORD)
 PG_KEYWORD("by", BY, UNRESERVED_KEYWORD)
 PG_KEYWORD("cache", CACHE, UNRESERVED_KEYWORD)
+PG_KEYWORD("call", CALL, UNRESERVED_KEYWORD)
 PG_KEYWORD("called", CALLED, UNRESERVED_KEYWORD)
 PG_KEYWORD("cascade", CASCADE, UNRESERVED_KEYWORD)
 PG_KEYWORD("cascaded", CASCADED, UNRESERVED_KEYWORD)
@@ -310,6 +311,7 @@ PG_KEYWORD("prior", PRIOR, UNRESERVED_KEYWORD)
 PG_KEYWORD("privileges", PRIVILEGES, UNRESERVED_KEYWORD)
 PG_KEYWORD("procedural", PROCEDURAL, UNRESERVED_KEYWORD)
 PG_KEYWORD("procedure", PROCEDURE, UNRESERVED_KEYWORD)
+PG_KEYWORD("procedures", PROCEDURES, UNRESERVED_KEYWORD)
 PG_KEYWORD("program", PROGRAM, UNRESERVED_KEYWORD)
 PG_KEYWORD("publication", PUBLICATION, UNRESERVED_KEYWORD)
 PG_KEYWORD("quote", QUOTE, UNRESERVED_KEYWORD)
@@ -340,6 +342,8 @@ PG_KEYWORD("right", RIGHT, TYPE_FUNC_NAME_KEYWORD)
 PG_KEYWORD("role", ROLE, UNRESERVED_KEYWORD)
 PG_KEYWORD("rollback", ROLLBACK, UNRESERVED_KEYWORD)
 PG_KEYWORD("rollup", ROLLUP, UNRESERVED_KEYWORD)
+PG_KEYWORD("routine", ROUTINE, UNRESERVED_KEYWORD)
+PG_KEYWORD("routines", ROUTINES, UNRESERVED_KEYWORD)
 PG_KEYWORD("row", ROW, COL_NAME_KEYWORD)
 PG_KEYWORD("rows", ROWS, UNRESERVED_KEYWORD)
 PG_KEYWORD("rule", RULE, UNRESERVED_KEYWORD)

src/include/parser/parse_func.h

@@ -24,6 +24,7 @@ typedef enum
 	FUNCDETAIL_NOTFOUND,		/* no matching function */
 	FUNCDETAIL_MULTIPLE,		/* too many matching functions */
 	FUNCDETAIL_NORMAL,			/* found a matching regular function */
+	FUNCDETAIL_PROCEDURE,		/* found a matching procedure */
 	FUNCDETAIL_AGGREGATE,		/* found a matching aggregate function */
 	FUNCDETAIL_WINDOWFUNC,		/* found a matching window function */
 	FUNCDETAIL_COERCION			/* it's a type coercion request */
@@ -31,7 +32,8 @@ typedef enum
 
 
 extern Node *ParseFuncOrColumn(ParseState *pstate, List *funcname, List *fargs,
-				  Node *last_srf, FuncCall *fn, int location);
+							   Node *last_srf, FuncCall *fn, bool proc_call,
+							   int location);
 
 extern FuncDetailCode func_get_detail(List *funcname,
 				List *fargs, List *fargnames,
@@ -62,10 +64,8 @@ extern const char *func_signature_string(List *funcname, int nargs,
 
 extern Oid LookupFuncName(List *funcname, int nargs, const Oid *argtypes,
 			   bool noError);
-extern Oid LookupFuncWithArgs(ObjectWithArgs *func,
+extern Oid LookupFuncWithArgs(ObjectType objtype, ObjectWithArgs *func,
 				   bool noError);
-extern Oid LookupAggWithArgs(ObjectWithArgs *agg,
-				  bool noError);
 
 extern void check_srf_call_placement(ParseState *pstate, Node *last_srf,
 						 int location);

src/include/parser/parse_node.h

@@ -67,7 +67,8 @@ typedef enum ParseExprKind
 	EXPR_KIND_EXECUTE_PARAMETER,	/* parameter value in EXECUTE */
 	EXPR_KIND_TRIGGER_WHEN,		/* WHEN condition in CREATE TRIGGER */
 	EXPR_KIND_POLICY,			/* USING or WITH CHECK expr in policy */
-	EXPR_KIND_PARTITION_EXPRESSION	/* PARTITION BY expression */
+	EXPR_KIND_PARTITION_EXPRESSION,	/* PARTITION BY expression */
+	EXPR_KIND_CALL				/* CALL argument */
 } ParseExprKind;