fixed bugs in temporary tables in subselect implementation (SCRUM)

merging with switching on static tables optimization (SCRUM)
fixed subselects with uncacheable results
added test for fixed bugs from bugreports


mysql-test/r/subselect.result:
  changes in subselect test after switching on static tables optimization
  fixed bug test added
  uncacheable subselects
mysql-test/t/subselect.test:
  changes in subselect test after switching on static tables optimization
  fixed bug test added
  uncacheable subselects
sql/item_create.cc:
  fixed subselects with uncacheable results
sql/item_func.cc:
  fixed subselects with uncacheable results
sql/item_subselect.cc:
  fixed subselects with uncacheable results
  clean up
sql/item_subselect.h:
  fixed subselects with uncacheable results
sql/sql_lex.cc:
  fixed subselects with uncacheable results
sql/sql_lex.h:
  fixed subselects with uncacheable results
sql/sql_select.cc:
  fixed bugs in temporary tables in subselect implementation
  fixed subselects with uncacheable results
sql/sql_union.cc:
  fixed subselects with uncacheable results
sql/sql_yacc.yy:
  fixed subselects with uncacheable results

1 files changed, 15 insertions, 8 deletions

diff --git a/sql/item_subselect.cc b/sql/item_subselect.cc
index 18a32b97a9f..ffb4d715159 100644
--- a/sql/item_subselect.cc
+++ b/sql/item_subselect.cc
@@ -129,7 +129,8 @@ void Item_subselect::fix_length_and_dec()
 
 inline table_map Item_subselect::used_tables() const
 {
-  return (table_map) engine->depended() ? 1L : 0L; 
+  return (table_map) (engine->dependent() ? 1L :
+		      (engine->uncacheable() ? RAND_TABLE_BIT : 0L));
 }
 
 Item_singlerow_subselect::Item_singlerow_subselect(THD *thd,
@@ -795,7 +796,7 @@ int subselect_single_select_engine::exec()
       DBUG_RETURN(join->error?join->error:1);
     }
   }
-  if (select_lex->dependent && executed)
+  if ((select_lex->dependent || select_lex->uncacheable) && executed)
   {
     if (join->reinit())
     {
@@ -837,16 +838,26 @@ uint subselect_union_engine::cols()
   return unit->first_select()->item_list.elements;
 }
 
-bool subselect_single_select_engine::depended()
+bool subselect_single_select_engine::dependent()
 {
   return select_lex->dependent;
 }
 
-bool subselect_union_engine::depended()
+bool subselect_union_engine::dependent()
 {
   return unit->dependent;
 }
 
+bool subselect_single_select_engine::uncacheable()
+{
+  return select_lex->uncacheable;
+}
+
+bool subselect_union_engine::uncacheable()
+{
+  return unit->uncacheable;
+}
+
 bool subselect_single_select_engine::check_loop(uint id)
 {
   DBUG_ENTER("subselect_single_select_engine::check_loop");
@@ -865,13 +876,9 @@ bool subselect_union_engine::check_loop(uint id)
 void subselect_single_select_engine::exclude()
 {
   select_lex->master_unit()->exclude_level();
-  //if (current_thd->lex->describe)
 }
 
 void subselect_union_engine::exclude()
 {
   unit->exclude_level();
-  // for (SELECT_LEX *sl= unit->first_select(); sl; sl= sl->next_select())
-  //  if (sl->join && sl->join->check_loop(id))
-  //    DBUG_RETURN(1);
 }