prevented finding references in item_list for non-SELECT st_select_lex

(fixed BUG#943)


mysql-test/r/subselect.result:
  test for bug 943
mysql-test/t/subselect.test:
  test for bug 943
sql/item.cc:
  bool field changed with enum
  prevented finding references in item_list for non-SELECT st_select_lex
sql/sql_lex.cc:
  bool field changed with enum
sql/sql_lex.h:
  bool field changed with enum
sql/sql_parse.cc:
  all subqueries and UNION parts marked as SELECT
sql/sql_yacc.yy:
  bool field changed with enum
  PRIMARY SELECT command st_select_lex marked as SELECT

mysql-test/r/subselect.result

@@ -1225,3 +1225,10 @@ a	(select count(distinct t1.b) as sum from t1,t2 where t1.a=t2.a and t2.b > 0 an
 2	2
 1	2
 drop table t1,t2,t3;
+create table t1 (s1 int);
+create table t2 (s1 int);
+insert into t1 values (1);
+insert into t2 values (1);
+update t1 set  s1 = s1 + 1 where 1 = (select x.s1 as A from t2 WHERE t2.s1 > t1.s1 order by A);
+ERROR 42S02: Unknown table 'x' in field list
+DROP TABLE t1, t2;

mysql-test/t/subselect.test

@@ -817,4 +817,17 @@ insert into t1 values (0,100),(1,2), (1,3), (2,2), (2,7), (2,-1), (3,10);
 insert into t2 values (0,0), (1,1), (2,1), (3,1), (4,1);
 insert into t3 values (3,3), (2,2), (1,1); 
 select a,(select count(distinct t1.b) as sum from t1,t2 where t1.a=t2.a and t2.b > 0 and t1.a <= t3.b group by t1.a order by sum limit 1) from t3;
-drop table t1,t2,t3;s
+drop table t1,t2,t3;
+
+#
+# update subquery with wrong field (to force name resolving
+# in UPDATE name space)
+#
+create table t1 (s1 int);
+create table t2 (s1 int);
+insert into t1 values (1);
+insert into t2 values (1);
+-- error 1109
+update t1 set  s1 = s1 + 1 where 1 = (select x.s1 as A from t2 WHERE t2.s1 > t1.s1 order by A);
+DROP TABLE t1, t2;
+

sql/item.cc

@@ -862,7 +862,7 @@ bool Item_field::fix_fields(THD *thd, TABLE_LIST *tables, Item **ref)
 	     sl= sl->outer_select())
 	{
 	  table_list= (last= sl)->get_table_list();
-	  if (sl->insert_select && table_list)
+	  if (sl->resolve_mode == SELECT_LEX::INSERT_MODE && table_list)
 	  {
 	    // it is primary INSERT st_select_lex => skip first table resolving
 	    table_list= table_list->next;
@@ -871,7 +871,8 @@ bool Item_field::fix_fields(THD *thd, TABLE_LIST *tables, Item **ref)
 					 table_list, &where,
 					 0)) != not_found_field)
 	    break;
-	  if ((refer= find_item_in_list(this, sl->item_list, &counter, 
+	  if (sl->resolve_mode == SELECT_LEX::SELECT_MODE &&
+	      (refer= find_item_in_list(this, sl->item_list, &counter, 
 					 REPORT_EXCEPT_NOT_FOUND)) != 
 	       (Item **) not_found_item)
 	    break;
@@ -1348,13 +1349,15 @@ bool Item_ref::fix_fields(THD *thd,TABLE_LIST *tables, Item **reference)
       SELECT_LEX *last=0;
       for ( ; sl ; sl= sl->outer_select())
       {
-	if ((ref= find_item_in_list(this, (last= sl)->item_list,
+	last= sl;
+	if (sl->resolve_mode == SELECT_LEX::SELECT_MODE &&
+	    (ref= find_item_in_list(this, sl->item_list,
 				    &counter,
 				    REPORT_EXCEPT_NOT_FOUND)) !=
 	   (Item **)not_found_item)
 	  break;
 	table_list= sl->get_table_list();
-	if (sl->insert_select && table_list)
+	if (sl->resolve_mode == SELECT_LEX::INSERT_MODE && table_list)
 	{
 	  // it is primary INSERT st_select_lex => skip first table resolving
 	  table_list= table_list->next;

sql/sql_lex.cc

@@ -986,7 +986,8 @@ void st_select_lex::init_query()
   join= 0;
   where= 0;
   olap= UNSPECIFIED_OLAP_TYPE;
-  insert_select= having_fix_field= 0;
+  having_fix_field= 0;
+  resolve_mode= NOMATTER_MODE;
   with_wild= 0;
 }
 

sql/sql_lex.h

@@ -360,14 +360,27 @@ class st_select_lex: public st_select_lex_node
   bool  braces;   	/* SELECT ... UNION (SELECT ... ) <- this braces */
   /* TRUE when having fix field called in processing of this SELECT */
   bool having_fix_field;
+
   /* 
-     TRUE for primary st_select_lex structure of simple INSERT/REPLACE
+     SELECT for SELECT command st_select_lex. Used to privent scaning
+     item_list of non-SELECT st_select_lex (no sense find to finding
+     reference in it (all should be in tables, it is dangerouse due
+     to order of fix_fields calling for non-SELECTs commands (item list
+     can be not fix_fieldsd)). This value will be assigned for
+     primary select (sql_yac.yy) and for any subquery and
+     UNION SELECT (sql_parse.cc mysql_new_select())
+
+
+     INSERT for primary st_select_lex structure of simple INSERT/REPLACE
      (used for name resolution, see Item_fiels & Item_ref fix_fields,
      FALSE for INSERT/REPLACE ... SELECT, because it's
      st_select_lex->table_list will be preprocessed (first table removed)
      before passing to handle_select)
+
+     NOMATTER for other
   */
-  bool insert_select;
+  enum {NOMATTER_MODE, SELECT_MODE, INSERT_MODE} resolve_mode;
+
 
   void init_query();
   void init_select();

sql/sql_parse.cc

@@ -3550,6 +3550,7 @@ mysql_new_select(LEX *lex, bool move_down)
     unit->link_prev= 0;
     unit->return_to= lex->current_select;
     select_lex->include_down(unit);
+    // TODO: assign resolve_mode for fake subquery after merging with new tree
   }
   else
     select_lex->include_neighbour(lex->current_select);
@@ -3557,6 +3558,7 @@ mysql_new_select(LEX *lex, bool move_down)
   select_lex->master_unit()->global_parameters= select_lex;
   select_lex->include_global((st_select_lex_node**)&lex->all_selects_list);
   lex->current_select= select_lex;
+  select_lex->resolve_mode= SELECT_LEX::SELECT_MODE;
   return 0;
 }
 

sql/sql_yacc.yy

@@ -1910,7 +1910,12 @@ opt_ignore_leaves:
 
 
 select:
-	select_init { Lex->sql_command=SQLCOM_SELECT; };
+	select_init
+	{
+	  LEX *lex= Lex;
+	  lex->sql_command= SQLCOM_SELECT;
+	  lex->select_lex.resolve_mode= SELECT_LEX::SELECT_MODE;
+	};
 
 /* Need select_init2 for subselects. */
 select_init:
@@ -3401,7 +3406,7 @@ insert:
 	  lex->sql_command = SQLCOM_INSERT;
 	  /* for subselects */
           lex->lock_option= (using_update_log) ? TL_READ_NO_INSERT : TL_READ;
-	  lex->select_lex.insert_select= 1;
+	  lex->select_lex.resolve_mode= SELECT_LEX::INSERT_MODE;
 	} insert_lock_option
 	opt_ignore insert2
 	{
@@ -3417,7 +3422,7 @@ replace:
 	  LEX *lex=Lex;
 	  lex->sql_command = SQLCOM_REPLACE;
 	  lex->duplicates= DUP_REPLACE;
-	  lex->select_lex.insert_select= 1;
+	  lex->select_lex.resolve_mode= SELECT_LEX::INSERT_MODE;
 	}
 	replace_lock_option insert2
 	{
@@ -3486,7 +3491,7 @@ insert_values:
 	      it is not simple select => table list will be
               preprocessed before passing to handle_select
 	    */
-	    lex->select_lex.insert_select= 0;
+	    lex->select_lex.resolve_mode= SELECT_LEX::NOMATTER_MODE;
 	    lex->current_select->parsing_place= SELECT_LEX_NODE::SELECT_LIST;
 	  }
 	  select_options select_item_list