diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 509422675001e25ee7f3a2a2b52988473bf8874b..c41f1b512f6b3a1da605bcfce37583c98aad6512 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -401,7 +401,7 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
%type <node> columnDef columnOptions
%type <defelt> def_elem reloption_elem old_aggr_elem
%type <node> def_arg columnElem where_clause where_or_current_clause
- a_expr b_expr c_expr func_expr AexprConst indirection_el
+ a_expr b_expr c_expr AexprConst indirection_el
columnref in_expr having_clause func_table array_expr
ExclusionWhereClause
%type <list> ExclusionConstraintList ExclusionConstraintElem
@@ -481,6 +481,8 @@ static Node *makeRecursiveViewSelect(char *relname, List *aliases, Node *query);
%type <ival> document_or_content
%type <boolean> xml_whitespace_option
+%type <node> func_application func_expr_common_subexpr
+%type <node> func_expr func_expr_windowless
%type <node> common_table_expr
%type <with> with_clause opt_with_clause
%type <list> cte_list
@@ -6132,7 +6134,7 @@ index_elem: ColId opt_collate opt_class opt_asc_desc opt_nulls_order
$$->ordering = $4;
$$->nulls_ordering = $5;
}
- | func_expr opt_collate opt_class opt_asc_desc opt_nulls_order
+ | func_expr_windowless opt_collate opt_class opt_asc_desc opt_nulls_order
{
$$ = makeNode(IndexElem);
$$->name = NULL;
@@ -9894,8 +9896,7 @@ relation_expr_opt_alias: relation_expr %prec UMINUS
}
;
-
-func_table: func_expr { $$ = $1; }
+func_table: func_expr_windowless { $$ = $1; }
;
@@ -11079,15 +11080,7 @@ c_expr: columnref { $$ = $1; }
}
;
-/*
- * func_expr is split out from c_expr just so that we have a classification
- * for "everything that is a function call or looks like one". This isn't
- * very important, but it saves us having to document which variants are
- * legal in the backwards-compatible functional-index syntax for CREATE INDEX.
- * (Note that many of the special SQL functions wouldn't actually make any
- * sense as functional index entries, but we ignore that consideration here.)
- */
-func_expr: func_name '(' ')' over_clause
+func_application: func_name '(' ')'
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
@@ -11096,11 +11089,11 @@ func_expr: func_name '(' ')' over_clause
n->agg_star = FALSE;
n->agg_distinct = FALSE;
n->func_variadic = FALSE;
- n->over = $4;
+ n->over = NULL;
n->location = @1;
$$ = (Node *)n;
}
- | func_name '(' func_arg_list ')' over_clause
+ | func_name '(' func_arg_list ')'
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
@@ -11109,11 +11102,11 @@ func_expr: func_name '(' ')' over_clause
n->agg_star = FALSE;
n->agg_distinct = FALSE;
n->func_variadic = FALSE;
- n->over = $5;
+ n->over = NULL;
n->location = @1;
$$ = (Node *)n;
}
- | func_name '(' VARIADIC func_arg_expr ')' over_clause
+ | func_name '(' VARIADIC func_arg_expr ')'
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
@@ -11122,11 +11115,11 @@ func_expr: func_name '(' ')' over_clause
n->agg_star = FALSE;
n->agg_distinct = FALSE;
n->func_variadic = TRUE;
- n->over = $6;
+ n->over = NULL;
n->location = @1;
$$ = (Node *)n;
}
- | func_name '(' func_arg_list ',' VARIADIC func_arg_expr ')' over_clause
+ | func_name '(' func_arg_list ',' VARIADIC func_arg_expr ')'
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
@@ -11135,11 +11128,11 @@ func_expr: func_name '(' ')' over_clause
n->agg_star = FALSE;
n->agg_distinct = FALSE;
n->func_variadic = TRUE;
- n->over = $8;
+ n->over = NULL;
n->location = @1;
$$ = (Node *)n;
}
- | func_name '(' func_arg_list sort_clause ')' over_clause
+ | func_name '(' func_arg_list sort_clause ')'
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
@@ -11148,11 +11141,11 @@ func_expr: func_name '(' ')' over_clause
n->agg_star = FALSE;
n->agg_distinct = FALSE;
n->func_variadic = FALSE;
- n->over = $6;
+ n->over = NULL;
n->location = @1;
$$ = (Node *)n;
}
- | func_name '(' ALL func_arg_list opt_sort_clause ')' over_clause
+ | func_name '(' ALL func_arg_list opt_sort_clause ')'
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
@@ -11165,11 +11158,11 @@ func_expr: func_name '(' ')' over_clause
* for that in FuncCall at the moment.
*/
n->func_variadic = FALSE;
- n->over = $7;
+ n->over = NULL;
n->location = @1;
$$ = (Node *)n;
}
- | func_name '(' DISTINCT func_arg_list opt_sort_clause ')' over_clause
+ | func_name '(' DISTINCT func_arg_list opt_sort_clause ')'
{
FuncCall *n = makeNode(FuncCall);
n->funcname = $1;
@@ -11178,11 +11171,11 @@ func_expr: func_name '(' ')' over_clause
n->agg_star = FALSE;
n->agg_distinct = TRUE;
n->func_variadic = FALSE;
- n->over = $7;
+ n->over = NULL;
n->location = @1;
$$ = (Node *)n;
}
- | func_name '(' '*' ')' over_clause
+ | func_name '(' '*' ')'
{
/*
* We consider AGGREGATE(*) to invoke a parameterless
@@ -11201,11 +11194,48 @@ func_expr: func_name '(' ')' over_clause
n->agg_star = TRUE;
n->agg_distinct = FALSE;
n->func_variadic = FALSE;
- n->over = $5;
+ n->over = NULL;
n->location = @1;
$$ = (Node *)n;
}
- | COLLATION FOR '(' a_expr ')'
+ ;
+
+
+/*
+ * func_expr and its cousin func_expr_windowless is split out from c_expr just
+ * so that we have classifications for "everything that is a function call or
+ * looks like one". This isn't very important, but it saves us having to document
+ * which variants are legal in the backwards-compatible functional-index syntax
+ * for CREATE INDEX.
+ * (Note that many of the special SQL functions wouldn't actually make any
+ * sense as functional index entries, but we ignore that consideration here.)
+ */
+func_expr: func_application over_clause
+ {
+ FuncCall *n = (FuncCall*)$1;
+ n->over = $2;
+ $$ = (Node*)n;
+ }
+ | func_expr_common_subexpr
+ { $$ = $1; }
+ ;
+
+/*
+ * As func_expr but does not accept WINDOW functions directly (they
+ * can still be contained in arguments for functions etc.)
+ * Use this when window expressions are not allowed, so to disambiguate
+ * the grammar. (e.g. in CREATE INDEX)
+ */
+func_expr_windowless:
+ func_application { $$ = $1; }
+ | func_expr_common_subexpr { $$ = $1; }
+ ;
+
+/*
+ * Special expression
+ */
+func_expr_common_subexpr:
+ COLLATION FOR '(' a_expr ')'
{
FuncCall *n = makeNode(FuncCall);
n->funcname = SystemFuncName("pg_collation_for");
@@ -12794,6 +12824,7 @@ unreserved_keyword:
| OPERATOR
| OPTION
| OPTIONS
+ | OVER
| OWNED
| OWNER
| PARSER
@@ -12992,7 +13023,6 @@ type_func_name_keyword:
| NATURAL
| NOTNULL
| OUTER_P
- | OVER
| OVERLAPS
| RIGHT
| SIMILAR
diff --git a/src/include/parser/kwlist.h b/src/include/parser/kwlist.h
index 68a13b7a7ba7fb77fabec033f39df98c5592a503..b3d72a9ae3b0082965c0c78a56477a40f8f1cd6c 100644
--- a/src/include/parser/kwlist.h
+++ b/src/include/parser/kwlist.h
@@ -270,7 +270,7 @@ PG_KEYWORD("or", OR, RESERVED_KEYWORD)
PG_KEYWORD("order", ORDER, RESERVED_KEYWORD)
PG_KEYWORD("out", OUT_P, COL_NAME_KEYWORD)
PG_KEYWORD("outer", OUTER_P, TYPE_FUNC_NAME_KEYWORD)
-PG_KEYWORD("over", OVER, TYPE_FUNC_NAME_KEYWORD)
+PG_KEYWORD("over", OVER, UNRESERVED_KEYWORD)
PG_KEYWORD("overlaps", OVERLAPS, TYPE_FUNC_NAME_KEYWORD)
PG_KEYWORD("overlay", OVERLAY, COL_NAME_KEYWORD)
PG_KEYWORD("owned", OWNED, UNRESERVED_KEYWORD)
diff --git a/src/test/regress/expected/window.out b/src/test/regress/expected/window.out
index 752c7b42ff341bf895405e5f3f558dedb1986e63..ecc1c2c6113da89bc625ac3b2def9cce7fa3b15f 100644
--- a/src/test/regress/expected/window.out
+++ b/src/test/regress/expected/window.out
@@ -989,9 +989,9 @@ ERROR: window functions are not allowed in GROUP BY
LINE 1: SELECT rank() OVER (ORDER BY 1), count(*) FROM empsalary GRO...
^
SELECT * FROM rank() OVER (ORDER BY random());
-ERROR: window functions are not allowed in functions in FROM
+ERROR: syntax error at or near "ORDER"
LINE 1: SELECT * FROM rank() OVER (ORDER BY random());
- ^
+ ^
DELETE FROM empsalary WHERE (rank() OVER (ORDER BY random())) > 10;
ERROR: window functions are not allowed in WHERE
LINE 1: DELETE FROM empsalary WHERE (rank() OVER (ORDER BY random())...