Fixed UNION support in view creation (BUG#4664)

mysql-test/r/view.result

@@ -830,7 +830,7 @@ a	b	c
 30	4	-60
 50	6	-100
 40	5	NULL
-drop table t1;
+drop table t1, t2;
 drop view v1,v2,v3,v4,v5;
 create database mysqltest;
 create table mysqltest.t1 (a int, b int, primary key(a));
@@ -1040,7 +1040,6 @@ CREATE VIEW v02 AS SELECT * FROM DUAL;
 ERROR HY000: No tables used
 SHOW TABLES;
 Tables_in_test	table_type
-t2	BASE TABLE
 v4	VIEW
 CREATE VIEW v1 AS SELECT EXISTS (SELECT 1 UNION SELECT 2);
 select * from v1;
@@ -1058,3 +1057,20 @@ SHOW CREATE VIEW v1;
 Table	Create Table
 v1	CREATE VIEW test.v1 AS select sql_no_cache connection_id() AS `f1`,pi() AS `f2`,current_user() AS `f3`,version() AS `f4`
 drop view v1;
+create table t1 (s1 int);
+create table t2 (s2 int);
+insert into t1 values (1), (2);
+insert into t2 values (2), (3);
+create view v1 as select * from t1,t2 union all select * from t1,t2;
+select * from v1;
+s1	s2
+1	2
+2	2
+1	3
+2	3
+1	2
+2	2
+1	3
+2	3
+drop view v1;
+drop tables t1, t2;

mysql-test/t/view.test

@@ -693,7 +693,7 @@ insert into v1 select c, b, a from t2;
 insert into v1 (z,y,x) select a+20,b+2,-100 from t2;
 insert into v2 select b+1, a+10 from t2;
 select * from t1;
-drop table t1;
+drop table t1, t2;
 drop view v1,v2,v3,v4,v5;
 
 #
@@ -1004,3 +1004,15 @@ drop table t1;
 CREATE VIEW v1 (f1,f2,f3,f4) AS SELECT connection_id(), pi(), current_user(), version();
 SHOW CREATE VIEW v1;
 drop view v1;
+
+#
+# VIEW built over UNION
+#
+create table t1 (s1 int);
+create table t2 (s2 int);
+insert into t1 values (1), (2);
+insert into t2 values (2), (3);
+create view v1 as select * from t1,t2 union all select * from t1,t2;
+select * from v1;
+drop view v1;
+drop tables t1, t2;

sql/sql_view.cc

@@ -54,7 +54,7 @@ int mysql_create_view(THD *thd,
   TABLE_LIST *view= lex->unlink_first_table(&link_to_local);
   TABLE_LIST *tables= lex->query_tables;
   TABLE_LIST *tbl;
-  SELECT_LEX *select_lex= &lex->select_lex;
+  SELECT_LEX *select_lex= &lex->select_lex, *sl;
   SELECT_LEX_UNIT *unit= &lex->unit;
   int res= 0;
   DBUG_ENTER("mysql_create_view");
@@ -74,7 +74,9 @@ int mysql_create_view(THD *thd,
                    0, 0) ||
       grant_option && check_grant(thd, CREATE_VIEW_ACL, view, 0, 1, 0))
     DBUG_RETURN(1);
-  for (tbl= tables; tbl; tbl= tbl->next_local)
+  for (sl= select_lex; sl; sl= sl->next_select())
+  {
+    for (tbl= sl->get_table_list(); tbl; tbl= tbl->next_local)
     {
       /*
         Ensure that we have some privilage on this table, more strict check
@@ -125,6 +127,7 @@ int mysql_create_view(THD *thd,
       fill_effective_table_privileges(thd, &tbl->grant, tbl->db,
                                       tbl->real_name);
     }
+  }
 
   if (&lex->select_lex != lex->all_selects_list)
   {
@@ -145,12 +148,10 @@ int mysql_create_view(THD *thd,
   }
   /*
     Mark fields for special privilege check (any privilege)
-
-    'if' should be changed if we made updateable UNION.
   */
-  if (lex->select_lex.next_select() == 0)
+  for (sl= select_lex; sl; sl= sl->next_select())
   {
-    List_iterator_fast<Item> it(lex->select_lex.item_list);
+    List_iterator_fast<Item> it(sl->item_list);
     Item *item;
     while ((item= it++))
     {
@@ -235,9 +236,10 @@ int mysql_create_view(THD *thd,
   /*
     Compare/check grants on view with grants of underlaying tables
   */
+  for (sl= select_lex; sl; sl= sl->next_select())
   {
     char *db= view->db ? view->db : thd->db;
-    List_iterator_fast<Item> it(select_lex->item_list);
+    List_iterator_fast<Item> it(sl->item_list);
     Item *item;
     fill_effective_table_privileges(thd, &view->grant, db,
                                     view->real_name);