Merge bk-internal.mysql.com:/home/bk/mysql-4.1

into mysql.com:/home/dlenev/src/mysql-4.1-bg4302


sql/item.cc:
  Auto merged

mysql-test/r/order_by.result

@@ -680,6 +680,9 @@ order by col;
 ERROR 23000: Column 'col' in order clause is ambiguous
 select col1 from t1, t2 where t1.col1=t2.col2 order by col;
 ERROR 23000: Column 'col' in order clause is ambiguous
+select t1.col as t1_col, t2.col2 from t1, t2 where t1.col1=t2.col2
+order by col;
+ERROR 23000: Column 'col' in order clause is ambiguous
 select t1.col as t1_col, t2.col from t1, t2 where t1.col1=t2.col2
 order by col;
 t1_col	col
@@ -696,12 +699,6 @@ col	col2
 1	3
 2	2
 3	1
-select t1.col as t1_col, t2.col2 from t1, t2 where t1.col1=t2.col2
-order by col;
-t1_col	col2
-1	1
-2	2
-3	3
 select t2.col2, t2.col, t2.col from t2 order by col;
 col2	col	col
 3	1	1

mysql-test/t/order_by.test

@@ -472,13 +472,14 @@ select t1.col as c1, t2.col as c2 from t1, t2 where t1.col1=t2.col2
   order by col;
 --error 1052
 select col1 from t1, t2 where t1.col1=t2.col2 order by col;
+--error 1052
+select t1.col as t1_col, t2.col2 from t1, t2 where t1.col1=t2.col2
+  order by col;
 
 select t1.col as t1_col, t2.col from t1, t2 where t1.col1=t2.col2
   order by col;
 select col2 as c, col as c from t2 order by col;
 select col2 as col, col as col2 from t2 order by col; 
-select t1.col as t1_col, t2.col2 from t1, t2 where t1.col1=t2.col2
-  order by col;
 select t2.col2, t2.col, t2.col from t2 order by col;
 
 select t2.col2 as col from t2 order by t2.col;

sql/item.cc

@@ -1246,6 +1246,7 @@ bool Item_field::fix_fields(THD *thd, TABLE_LIST *tables, Item **ref)
       TABLE_LIST *table_list;
       Item **refer= (Item **)not_found_item;
       uint counter;
+      bool not_used;
       // Prevent using outer fields in subselects, that is not supported now
       SELECT_LEX *cursel= (SELECT_LEX *) thd->lex->current_select;
       if (cursel->master_unit()->first_select()->linkage != DERIVED_TABLE_TYPE)
@@ -1288,7 +1289,8 @@ bool Item_field::fix_fields(THD *thd, TABLE_LIST *tables, Item **ref)
           }
 	  if (sl->resolve_mode == SELECT_LEX::SELECT_MODE &&
 	      (refer= find_item_in_list(this, sl->item_list, &counter,
-					 REPORT_EXCEPT_NOT_FOUND)) !=
+                                        REPORT_EXCEPT_NOT_FOUND,
+                                        &not_used)) !=
 	       (Item **) not_found_item)
 	  {
 	    if (*refer && (*refer)->fixed) // Avoid crash in case of error
@@ -1889,6 +1891,7 @@ bool Item_ref::fix_fields(THD *thd,TABLE_LIST *tables, Item **reference)
 {
   DBUG_ASSERT(fixed == 0);
   uint counter;
+  bool not_used;
   if (!ref)
   {
     TABLE_LIST *where= 0, *table_list;
@@ -1908,13 +1911,13 @@ bool Item_ref::fix_fields(THD *thd,TABLE_LIST *tables, Item **reference)
 				  first_select()->linkage !=
 				  DERIVED_TABLE_TYPE) ? 
 				  REPORT_EXCEPT_NOT_FOUND :
-				  REPORT_ALL_ERRORS))) ==
+				  REPORT_ALL_ERRORS ), &not_used)) ==
 	(Item **)not_found_item)
     {
       upward_lookup= 1;
       Field *tmp= (Field*) not_found_field;
       /*
-	We can't find table field in table list of current select,
+	We can't find table field in select list of current select,
 	consequently we have to find it in outer subselect(s).
 	We can't join lists of outer & current select, because of scope
 	of view rules. For example if both tables (outer & current) have
@@ -1929,8 +1932,8 @@ bool Item_ref::fix_fields(THD *thd,TABLE_LIST *tables, Item **reference)
 	Item_subselect *prev_subselect_item= prev_unit->item;
 	if (sl->resolve_mode == SELECT_LEX::SELECT_MODE &&
 	    (ref= find_item_in_list(this, sl->item_list,
-				    &counter,
-				    REPORT_EXCEPT_NOT_FOUND)) !=
+                                    &counter, REPORT_EXCEPT_NOT_FOUND,
+                                    &not_used)) !=
 	   (Item **)not_found_item)
 	{
 	  if (*ref && (*ref)->fixed) // Avoid crash in case of error
@@ -1989,8 +1992,7 @@ bool Item_ref::fix_fields(THD *thd,TABLE_LIST *tables, Item **reference)
 	  // Call to report error
 	  find_item_in_list(this,
 			    *(thd->lex->current_select->get_item_list()),
-			    &counter,
-			    REPORT_ALL_ERRORS);
+			    &counter, REPORT_ALL_ERRORS, &not_used);
 	}
         ref= 0;
 	return 1;

sql/mysql_priv.h

@@ -705,7 +705,8 @@ enum find_item_error_report_type {REPORT_ALL_ERRORS, REPORT_EXCEPT_NOT_FOUND,
 				  IGNORE_ERRORS};
 extern const Item **not_found_item;
 Item ** find_item_in_list(Item *item, List<Item> &items, uint *counter,
-			  find_item_error_report_type report_error);
+                          find_item_error_report_type report_error,
+                          bool *unaliased);
 bool get_key_map_from_key_list(key_map *map, TABLE *table,
                                List<String> *index_list);
 bool insert_fields(THD *thd,TABLE_LIST *tables,

sql/sql_base.cc

@@ -2082,6 +2082,9 @@ find_field_in_tables(THD *thd, Item_ident *item, TABLE_LIST *tables,
 				return not_found_item, report other errors,
 				return 0
       IGNORE_ERRORS		Do not report errors, return 0 if error
+    unaliased                   Set to true if item is field which was found
+                                by original field name and not by its alias
+                                in item list. Set to false otherwise.
 
   RETURN VALUES
     0			Item is not found or item is not unique,
@@ -2098,7 +2101,7 @@ const Item **not_found_item= (const Item**) 0x1;
 
 Item **
 find_item_in_list(Item *find, List<Item> &items, uint *counter,
-		  find_item_error_report_type report_error)
+                  find_item_error_report_type report_error, bool *unaliased)
 {
   List_iterator<Item> li(items);
   Item **found=0, **found_unaliased= 0, *item;
@@ -2107,6 +2110,9 @@ find_item_in_list(Item *find, List<Item> &items, uint *counter,
   const char *table_name=0;
   bool found_unaliased_non_uniq= 0;
   uint unaliased_counter;
+
+  *unaliased= FALSE;
+
   if (find->type() == Item::FIELD_ITEM	|| find->type() == Item::REF_ITEM)
   {
     field_name= ((Item_ident*) find)->field_name;
@@ -2134,17 +2140,18 @@ find_item_in_list(Item *find, List<Item> &items, uint *counter,
         /*
           If table name is specified we should find field 'field_name' in
           table 'table_name'. According to SQL-standard we should ignore
-          aliases in this case. Note that we should prefer fields from the
-          select list over other fields from the tables participating in
-          this select in case of ambiguity.
+          aliases in this case.
+
+          Since we should NOT prefer fields from the select list over
+          other fields from the tables participating in this select in
+          case of ambiguity we have to do extra check outside this function.
 
           We use strcmp for table names and database names as these may be
-          case sensitive.
-          In cases where they are not case sensitive, they are always in lower
-          case.
+          case sensitive. In cases where they are not case sensitive, they
+          are always in lower case.
 
 	  item_field->field_name and item_field->table_name can be 0x0 if
-	  item is not fix fielded yet.
+	  item is not fix_field()'ed yet.
         */
         if (item_field->field_name && item_field->table_name &&
 	    !my_strcasecmp(system_charset_info, item_field->field_name,
@@ -2153,17 +2160,22 @@ find_item_in_list(Item *find, List<Item> &items, uint *counter,
             (!db_name || (item_field->db_name &&
                           !strcmp(item_field->db_name, db_name))))
         {
-          if (found)
+          if (found_unaliased)
           {
-            if ((*found)->eq(item, 0))
-              continue;                         // Same field twice
+            if ((*found_unaliased)->eq(item, 0))
+              continue;
+            /*
+              Two matching fields in select list.
+              We already can bail out because we are searching through
+              unaliased names only and will have duplicate error anyway.
+            */
             if (report_error != IGNORE_ERRORS)
               my_printf_error(ER_NON_UNIQ_ERROR, ER(ER_NON_UNIQ_ERROR),
                               MYF(0), find->full_name(), current_thd->where);
             return (Item**) 0;
           }
-          found= li.ref();
-          *counter= i;
+          found_unaliased= li.ref();
+          unaliased_counter= i;
           if (db_name)
             break;                              // Perfect match
         }
@@ -2235,6 +2247,7 @@ find_item_in_list(Item *find, List<Item> &items, uint *counter,
     {
       found= found_unaliased;
       *counter= unaliased_counter;
+      *unaliased= TRUE;
     }
   }
   if (found)

sql/sql_select.cc

@@ -7946,15 +7946,14 @@ find_order_in_list(THD *thd, Item **ref_pointer_array,
 		   TABLE_LIST *tables,ORDER *order, List<Item> &fields,
 		   List<Item> &all_fields)
 {
-  Item *itemptr=*order->item;
-  if (itemptr->type() == Item::INT_ITEM)
+  Item *it= *order->item;
+  if (it->type() == Item::INT_ITEM)
   {						/* Order by position */
-    uint count= (uint) itemptr->val_int();
+    uint count= (uint) it->val_int();
     if (!count || count > fields.elements)
     {
       my_printf_error(ER_BAD_FIELD_ERROR,ER(ER_BAD_FIELD_ERROR),
-		      MYF(0),itemptr->full_name(),
-	       thd->where);
+		      MYF(0), it->full_name(), thd->where);
       return 1;
     }
     order->item= ref_pointer_array + count-1;
@@ -7962,20 +7961,28 @@ find_order_in_list(THD *thd, Item **ref_pointer_array,
     return 0;
   }
   uint counter;
-  Item **item= find_item_in_list(itemptr, fields, &counter,
-                                 REPORT_EXCEPT_NOT_FOUND);
+  bool unaliased;
+  Item **item= find_item_in_list(it, fields, &counter,
+                                 REPORT_EXCEPT_NOT_FOUND, &unaliased);
   if (!item)
     return 1;
 
   if (item != (Item **)not_found_item)
   {
+    /*
+      If we have found field not by its alias in select list but by its
+      original field name, we should additionaly check if we have conflict
+      for this name (in case if we would perform lookup in all tables).
+    */
+    if (unaliased && !it->fixed && it->fix_fields(thd, tables, order->item))
+      return 1;
+
     order->item= ref_pointer_array + counter;
     order->in_field_list=1;
     return 0;
   }
 
   order->in_field_list=0;
-  Item *it= *order->item;
   /*
     We check it->fixed because Item_func_group_concat can put
     arguments for which fix_fields already was called.
@@ -8104,10 +8111,11 @@ setup_new_fields(THD *thd,TABLE_LIST *tables,List<Item> &fields,
 
   thd->set_query_id=1;				// Not really needed, but...
   uint counter;
+  bool not_used;
   for (; new_field ; new_field= new_field->next)
   {
     if ((item= find_item_in_list(*new_field->item, fields, &counter,
-				 IGNORE_ERRORS)))
+				 IGNORE_ERRORS, &not_used)))
       new_field->item=item;			/* Change to shared Item */
     else
     {