Update UNION and subselect syntax.

Support SQL92 syntax for type coersion of strings (type 'typeval').
 Example: "DATETIME 'now'". This works only for string constants and can
 not replace the CAST and ::type syntax which behave identically in this
 context.

diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index ab14e80ba1eceef83bdf52268495f7354fffd6e0..333a42f55d5de129aee4a7f8f08751cea1ad72b5 100644 (file)
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -10,7 +10,7 @@
  *
  *
  * IDENTIFICATION
- *   $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 1.67 1997/11/15 20:57:09 momjian Exp $
+ *   $Header: /cvsroot/pgsql/src/backend/parser/gram.y,v 1.68 1997/11/17 16:37:24 thomas Exp $
  *
  * HISTORY
  *   AUTHOR            DATE            MAJOR EVENT
@@ -153,7 +153,9 @@ static Node *makeIndexable(char *opname, Node *lexpr, Node *rexpr);
 
 %type    union_clause, select_list
 %type    join_list
-%type         join_using
+%type 
+               join_using
+%type     opt_union
 
 %type    position_expr
 %type    extract_list, position_list
@@ -1130,7 +1132,7 @@ FetchStmt:    FETCH opt_direction fetch_how_many opt_portal_name
                    n->direction = $2;
                    n->howMany = $3;
                    n->portalname = $4;
-                   n->ismove = true;
+                   n->ismove = TRUE;
                    $$ = (Node *)n;
                }
        ;
@@ -2097,27 +2099,27 @@ RetrieveStmt:  SELECT opt_unique res_target_list2
                }
        ;
 
-union_clause:  UNION select_list               { $$ = $2; }
+union_clause:  UNION opt_union select_list     { $$ = $3; }
        | /*EMPTY*/                             { $$ = NIL; }
        ;
 
-select_list:  select_list UNION SubSelect
-               { $$ = lappend($1, $3); }
+select_list:  select_list UNION opt_union SubSelect
+               { $$ = lappend($1, $4); }
        | SubSelect
                { $$ = lcons($1, NIL); }
        ;
 
 SubSelect: SELECT opt_unique res_target_list2
-            result from_clause where_clause
+            from_clause where_clause
             group_clause having_clause
                {
                    SubSelect *n = makeNode(SubSelect);
                    n->unique = $2;
                    n->targetList = $3;
-                   n->fromClause = $5;
-                   n->whereClause = $6;
-                   n->groupClause = $7;
-                   n->havingClause = $8;
+                   n->fromClause = $4;
+                   n->whereClause = $5;
+                   n->groupClause = $6;
+                   n->havingClause = $7;
                    $$ = (Node *)n;
                }
        ;
@@ -2128,9 +2130,14 @@ result:  INTO TABLE relation_name
                {  $$ = NULL;  }
        ;
 
+opt_union:  ALL                                    { $$ = TRUE; }
+       | /*EMPTY*/                             { $$ = FALSE; }
+       ;
+
 opt_unique:  DISTINCT                          { $$ = "*"; }
        | DISTINCT ON ColId                     { $$ = $3; }
-       | /*EMPTY*/                             { $$ = NULL;}
+       | ALL                                   { $$ = NULL; }
+       | /*EMPTY*/                             { $$ = NULL; }
        ;
 
 sort_clause:  ORDER BY sortby_list             { $$ = $3; }
@@ -3416,6 +3423,14 @@ AexprConst:  Iconst
                    n->val.val.str = $1;
                    $$ = (Node *)n;
                }
+       | Typename Sconst
+               {
+                   A_Const *n = makeNode(A_Const);
+                   n->typename = $1;
+                   n->val.type = T_String;
+                   n->val.val.str = $2;
+                   $$ = (Node *)n;
+               }
        | ParamNo
                {   $$ = (Node *)$1;  }
        | TRUE_P