processing of subselect in global ORDER BY (fifed crash of server)

  this implementation have limitation: prohibited subselect in ORDER BY dependence of most outer query (will be solved after removing passing first select_lex as fake select for global mysql_select())


mysql-test/r/subselect.result:
  test of subselect in global ORDER BY
mysql-test/t/subselect.test:
  test of subselect in global ORDER BY
sql/sql_lex.cc:
  fixed comments
  processing of subselect in global ORDER BY
sql/sql_lex.h:
  processing of subselect in global ORDER BY
sql/sql_parse.cc:
  processing of subselect in global ORDER BY
sql/sql_yacc.yy:
  processing of subselect in global ORDER BY

mysql-test/r/subselect.result

@@ -458,6 +458,14 @@ Subselect returns more than 1 record
 select numeropost as a FROM t1 ORDER BY (SELECT 1 FROM t1 HAVING a=1);
 Subselect returns more than 1 record
 drop table t1;
+create table t1 (a int);
+insert into t1 values (1),(2),(3);
+(select * from t1) union (select * from t1) order by (select a from t1 limit 1);
+a
+1
+2
+3
+drop table t1;
 CREATE TABLE t1 (field char(1) NOT NULL DEFAULT 'b');
 INSERT INTO t1 VALUES ();
 SELECT field FROM t1 WHERE 1=(SELECT 1 UNION ALL SELECT 1 FROM (SELECT 1) a HAVING field='b');

mysql-test/t/subselect.test

@@ -244,6 +244,11 @@ select numeropost as a FROM t1 GROUP BY (SELECT 1 FROM t1 HAVING a=1);
 select numeropost as a FROM t1 ORDER BY (SELECT 1 FROM t1 HAVING a=1);
 drop table t1;
 
+create table t1 (a int);
+insert into t1 values (1),(2),(3);
+(select * from t1) union (select * from t1) order by (select a from t1 limit 1);
+drop table t1;
+
 #iftest
 CREATE TABLE t1 (field char(1) NOT NULL DEFAULT 'b');
 INSERT INTO t1 VALUES ();

sql/sql_lex.cc

@@ -1240,23 +1240,60 @@ TABLE_LIST *st_select_lex_node::add_table_to_list(THD *thd, Table_ident *table,
 }
 ulong st_select_lex_node::get_table_join_options() { return 0; }
 
-/*
-  This is used for UNION & subselect to create a new table list of all used 
-  tables.
-  The table_list->table entry in all used tables are set to point
-  to the entries in this list.
-*/
 
-// interface
+/*  
+  Interface method of table list creation for query
+  
+  SYNOPSIS
+    st_select_lex_unit::create_total_list()
+    thd            THD pointer
+    result         pointer on result list of tables pointer
+    check_derived  force derived table chacking (used for creating 
+                   table list for derived query)
+  DESCRIPTION
+    This is used for UNION & subselect to create a new table list of all used 
+    tables.
+    The table_list->table entry in all used tables are set to point
+    to the entries in this list.
+
+  RETURN
+    0 - OK
+    !0 - error
+*/
 bool st_select_lex_unit::create_total_list(THD *thd, st_lex *lex,
 					   TABLE_LIST **result,
 					   bool check_derived)
 {
   *result= 0;
-  return create_total_list_n_last_return(thd, lex, &result, check_derived);
+  for (SELECT_LEX_UNIT *unit= this; unit; unit= unit->next_unit())
+  {
+    if ((res= unit->create_total_list_n_last_return(thd, lex, &result,
+						    check_derived)))
+      return res;
+  }
+  return 0;
 }
 
-// list creator
+/*  
+  Table list creation for query
+  
+  SYNOPSIS
+    st_select_lex_unit::create_total_list()
+    thd            THD pointer
+    lex            pointer on LEX stricture
+    result         pointer on pointer on result list of tables pointer
+    check_derived  force derived table chacking (used for creating 
+                   table list for derived query)
+  DESCRIPTION
+    This is used for UNION & subselect to create a new table list of all used 
+    tables.
+    The table_list->table entry in all used tables are set to point
+    to the entries in this list.
+
+  RETURN
+    0 - OK
+    !0 - error
+*/
 bool st_select_lex_unit::create_total_list_n_last_return(THD *thd, st_lex *lex,
 							 TABLE_LIST ***result,
 							 bool check_derived)

sql/sql_lex.h

@@ -243,6 +243,7 @@ public:
 
   virtual st_select_lex_unit* master_unit()= 0;
   virtual st_select_lex* outer_select()= 0;
+  virtual st_select_lex_node* return_after_parsing()= 0;
 
   virtual bool set_braces(bool value);
   virtual bool inc_in_sum_expr();
@@ -297,6 +298,8 @@ public:
     global parameters for union
   */
   st_select_lex_node *global_parameters;
+  //node on wich we should return current_select pointer after parsing subquery
+  st_select_lex_node *return_to;
   /* LIMIT clause runtime counters */
   ha_rows select_limit_cnt, offset_limit_cnt;
   /* not NULL if union used in subselect, point to subselect item */
@@ -317,6 +320,7 @@ public:
       (st_select_lex*) slave->next : (st_select_lex*) slave;
   }
   st_select_lex_unit* next_unit() { return (st_select_lex_unit*) next; }
+  st_select_lex_node* return_after_parsing() { return return_to; }
   void exclude_level();
 
   /* UNION methods */
@@ -379,6 +383,10 @@ public:
   {
     return &link_next;
   }
+  st_select_lex_node* return_after_parsing()
+  {
+    return master_unit()->return_after_parsing();
+  }
 
   bool set_braces(bool value);
   bool inc_in_sum_expr();

sql/sql_parse.cc

@@ -3204,7 +3204,8 @@ mysql_init_query(THD *thd)
   lex->select_lex.init_query();
   lex->value_list.empty();
   lex->param_list.empty();
-  lex->unit.next= lex->unit.master= lex->unit.link_next= 0;
+  lex->unit.next= lex->unit.master= lex->unit.return_to= 
+    lex->unit.link_next= 0;
   lex->unit.prev= lex->unit.link_prev= 0;
   lex->unit.global_parameters= lex->unit.slave= lex->current_select=
     lex->all_selects_list= &lex->select_lex;
@@ -3252,9 +3253,9 @@ bool
 mysql_new_select(LEX *lex, bool move_down)
 {
   SELECT_LEX *select_lex = new SELECT_LEX();
-  select_lex->select_number= ++lex->thd->select_number;
   if (!select_lex)
     return 1;
+  select_lex->select_number= ++lex->thd->select_number;
   select_lex->init_query();
   select_lex->init_select();
   if (move_down)
@@ -3266,9 +3267,13 @@ mysql_new_select(LEX *lex, bool move_down)
     unit->init_query();
     unit->init_select();
     unit->thd= lex->thd;
-    unit->include_down(lex->current_select);
+    if (lex->current_select->linkage == GLOBAL_OPTIONS_TYPE)
+      unit->include_neighbour(lex->current_select);
+    else
+      unit->include_down(lex->current_select);
     unit->link_next= 0;
     unit->link_prev= 0;
+    unit->return_to= lex->current_select;
     select_lex->include_down(unit);
   }
   else

sql/sql_yacc.yy

@@ -4855,5 +4855,5 @@ subselect_end:
 	')'
 	{
 	  LEX *lex=Lex;
-	  lex->current_select = lex->current_select->outer_select();
+	  lex->current_select = lex->current_select->return_after_parsing();
 	};