Merge epotemkin@bk-internal.mysql.com:/home/bk/mysql-5.0

into moonbone.local:/work/mysql-5.0-bug-11864


mysql-test/r/derived.result:
  Auto merged
sql/sql_derived.cc:
  Auto merged
sql/sql_view.cc:
  Auto merged

mysql-test/r/derived.result

@@ -111,7 +111,7 @@ a	b
 1	a
 2	b
 3	c
-explain select * from (select * from t1,t2 where t1.a=t2.a) t1;
+explain select * from (select t1.*, t2.a as t2a from t1,t2 where t1.a=t2.a) t1;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	<derived2>	system	NULL	NULL	NULL	NULL	1	
 2	DERIVED	t2	system	NULL	NULL	NULL	NULL	1	
@@ -363,3 +363,8 @@ a
 3
 3
 drop table t1, t2, t3;
+create table t1 (a int);
+create table t2 (a int);
+select * from (select * from t1,t2) foo;
+ERROR 42S21: Duplicate column name 'a'
+drop table t1,t2;

mysql-test/r/select_safe.result

@@ -84,7 +84,7 @@ set local  max_join_size=8;
 select * from (select * from t1) x;
 ERROR 42000: The SELECT would examine more than MAX_JOIN_SIZE rows; check your WHERE and use SET SQL_BIG_SELECTS=1 or SET SQL_MAX_JOIN_SIZE=# if the SELECT is okay
 set local  max_join_size=1;
-select * from (select * from t1 a, t1 b) x;
+select * from (select a.a as aa, b.a as ba from t1 a, t1 b) x;
 ERROR 42000: The SELECT would examine more than MAX_JOIN_SIZE rows; check your WHERE and use SET SQL_BIG_SELECTS=1 or SET SQL_MAX_JOIN_SIZE=# if the SELECT is okay
 set local  max_join_size=1;
 select * from (select 1 union select 2 union select 3) x;

mysql-test/t/derived.test

@@ -42,7 +42,7 @@ CREATE TABLE t2 (a int not null);
 insert into t2 values(1);
 select * from (select * from t1 where t1.a=(select a from t2 where t2.a=t1.a)) a;
 select * from (select * from t1 where t1.a=(select t2.a from t2 where t2.a=t1.a) union select t1.a, t1.b from t1) a;
-explain select * from (select * from t1,t2 where t1.a=t2.a) t1;
+explain select * from (select t1.*, t2.a as t2a from t1,t2 where t1.a=t2.a) t1;
 drop table t1, t2;
 create table t1(a int not null, t char(8), index(a));
 disable_query_log;
@@ -249,4 +249,13 @@ select * from t1 union distinct select * from t2 union all select * from t3;
 select * from (select * from t1 union distinct select * from t2 union all select * from t3) X;
 drop table t1, t2, t3;
 
+#
+# Bug #11864 non unique names are allowed in subquery
+#
+create table t1 (a int);
+create table t2 (a int);
+--error 1060
+select * from (select * from t1,t2) foo;
+drop table t1,t2;
+
 # End of 4.1 tests

mysql-test/t/select_safe.test

@@ -78,7 +78,7 @@ select * from (select * from t1) x;
 
 set local  max_join_size=1;
 --error 1104
-select * from (select * from t1 a, t1 b) x;
+select * from (select a.a as aa, b.a as ba from t1 a, t1 b) x;
 
 set local  max_join_size=1;
 --error 1104

sql/sql_derived.cc

@@ -125,6 +125,11 @@ int mysql_derived_prepare(THD *thd, LEX *lex, TABLE_LIST *orig_table_list)
     if ((res= unit->prepare(thd, derived_result, 0, orig_table_list->alias)))
       goto exit;
 
+    if (check_duplicate_names(unit->types, 0))
+    {
+      res= -1;
+      goto exit;
+    }
 
     derived_result->tmp_table_param.init();
     derived_result->tmp_table_param.field_count= unit->types.elements;

sql/sql_view.cc

@@ -94,6 +94,71 @@ static void make_unique_view_field_name(Item *target,
   target->set_name(buff, name_len, system_charset_info);
 }
 
+
+/*
+  Check if items with same names are present in list and possibly
+  generate unique names for them.
+
+  SYNOPSIS
+    item_list             list of Items which should be checked for duplicates
+    gen_unique_view_name  flag: generate unique name or return with error when
+                          duplicate names are found.
+
+  DESCRIPTION
+    This function is used on view creation and preparation of derived tables.
+    It checks item_list for items with duplicate names. If it founds two
+    items with same name and conversion to unique names isn't allowed, or
+    names for both items are set by user - function fails.
+    Otherwise it generates unique name for one item with autogenerated name
+    using make_unique_view_field_name()
+
+  RETURN VALUE
+    FALSE no duplicate names found, or they are converted to unique ones
+    TRUE  duplicate names are found and they can't be converted or conversion
+          isn't allowed
+*/
+
+bool check_duplicate_names(List<Item> &item_list, bool gen_unique_view_name)
+{
+  DBUG_ENTER("check_duplicate_names");
+  /* Test absence of duplicates names */
+  {
+    Item *item;
+    List_iterator_fast<Item> it(item_list);
+    List_iterator_fast<Item> itc(item_list);
+    while ((item= it++))
+    {
+      Item *check;
+      /* treat underlying fields like set by user names */
+      if (item->real_item()->type() == Item::FIELD_ITEM)
+        item->is_autogenerated_name= FALSE;
+      itc.rewind();
+      while ((check= itc++) && check != item)
+      {
+        if (my_strcasecmp(system_charset_info, item->name, check->name) == 0)
+        {
+          if (!gen_unique_view_name)
+          {
+            my_error(ER_DUP_FIELDNAME, MYF(0), item->name);
+            DBUG_RETURN(TRUE);
+          }
+          else if (item->is_autogenerated_name)
+            make_unique_view_field_name(item, item_list, item);
+          else if (check->is_autogenerated_name)
+            make_unique_view_field_name(check, item_list, item);
+          else
+          {
+            my_error(ER_DUP_FIELDNAME, MYF(0), item->name);
+            DBUG_RETURN(TRUE);
+          }
+        }
+      }
+    }
+  }
+  DBUG_RETURN(FALSE);
+}
+
+
 /*
   Creating/altering VIEW procedure
 
@@ -308,35 +373,8 @@ bool mysql_create_view(THD *thd,
     }
   }
 
-  /* Test absence of duplicates names */
-  {
-    Item *item;
-    List_iterator_fast<Item> it(select_lex->item_list);
-    List_iterator_fast<Item> itc(select_lex->item_list);
-    while ((item= it++))
-    {
-      Item *check;
-      /* treat underlying fields like set by user names */
-      if (item->real_item()->type() == Item::FIELD_ITEM)
-        item->is_autogenerated_name= FALSE;
-      itc.rewind();
-      while ((check= itc++) && check != item)
-      {
-        if (my_strcasecmp(system_charset_info, item->name, check->name) == 0)
-        {
-          if (item->is_autogenerated_name)
-            make_unique_view_field_name(item, select_lex->item_list, item);
-          else if (check->is_autogenerated_name)
-            make_unique_view_field_name(check, select_lex->item_list, item);
-          else
-          {
-            my_error(ER_DUP_FIELDNAME, MYF(0), item->name);
-            DBUG_RETURN(TRUE);
-          }
-        }
-      }
-    }
-  }
+  if (check_duplicate_names(select_lex->item_list, 1))
+    DBUG_RETURN(TRUE);
 
 #ifndef NO_EMBEDDED_ACCESS_CHECKS
   /*

sql/sql_view.h

@@ -33,5 +33,7 @@ int view_checksum(THD *thd, TABLE_LIST *view);
 
 extern TYPELIB updatable_views_with_limit_typelib;
 
+bool check_duplicate_names(List<Item>& item_list, bool gen_unique_view_names);
+
 #define VIEW_ANY_ACL (SELECT_ACL | UPDATE_ACL | INSERT_ACL | DELETE_ACL)