Merge with 5.1-release.

- Fixed problem with oqgraph and 'make dist'

Note that after this merge we have a problem show in join_outer where we examine too many rows in one specific case (related to BUG#57024).
This will be fixed when mwl#128 is merged into 5.3.

1 files changed, 44 insertions, 42 deletions

diff --git a/sql/item_subselect.cc b/sql/item_subselect.cc
index c9d82ce4421..79a453333ee 100644
--- a/sql/item_subselect.cc
+++ b/sql/item_subselect.cc
@@ -45,7 +45,7 @@ Item_subselect::Item_subselect():
     Item value is NULL if select_result_interceptor didn't change this value
     (i.e. some rows will be found returned)
   */
-  null_value= 1;
+  null_value= TRUE;
 }
 
 
@@ -721,9 +721,9 @@ void Item_maxmin_subselect::print(String *str, enum_query_type query_type)
 void Item_singlerow_subselect::reset()
 {
   eliminated= FALSE;
-  null_value= 1;
+  null_value= TRUE;
   if (value)
-    value->null_value= 1;
+    value->null_value= TRUE;
 }
 
 
@@ -898,7 +898,10 @@ bool Item_singlerow_subselect::null_inside()
 
 void Item_singlerow_subselect::bring_value()
 {
-  exec();
+  if (!exec() && assigned())
+    null_value= 0;
+  else
+    reset();
 }
 
 double Item_singlerow_subselect::val_real()
@@ -906,7 +909,7 @@ double Item_singlerow_subselect::val_real()
   DBUG_ASSERT(fixed == 1);
   if (!exec() && !value->null_value)
   {
-    null_value= 0;
+    null_value= FALSE;
     return value->val_real();
   }
   else
@@ -921,7 +924,7 @@ longlong Item_singlerow_subselect::val_int()
   DBUG_ASSERT(fixed == 1);
   if (!exec() && !value->null_value)
   {
-    null_value= 0;
+    null_value= FALSE;
     return value->val_int();
   }
   else
@@ -935,7 +938,7 @@ String *Item_singlerow_subselect::val_str(String *str)
 {
   if (!exec() && !value->null_value)
   {
-    null_value= 0;
+    null_value= FALSE;
     return value->val_str(str);
   }
   else
@@ -950,7 +953,7 @@ my_decimal *Item_singlerow_subselect::val_decimal(my_decimal *decimal_value)
 {
   if (!exec() && !value->null_value)
   {
-    null_value= 0;
+    null_value= FALSE;
     return value->val_decimal(decimal_value);
   }
   else
@@ -965,7 +968,7 @@ bool Item_singlerow_subselect::val_bool()
 {
   if (!exec() && !value->null_value)
   {
-    null_value= 0;
+    null_value= FALSE;
     return value->val_bool();
   }
   else
@@ -983,7 +986,7 @@ Item_exists_subselect::Item_exists_subselect(st_select_lex *select_lex):
   bool val_bool();
   init(select_lex, new select_exists_subselect(this));
   max_columns= UINT_MAX;
-  null_value= 0; //can't be NULL
+  null_value= FALSE; //can't be NULL
   maybe_null= 0; //can't be NULL
   value= 0;
   DBUG_VOID_RETURN;
@@ -1186,15 +1189,14 @@ double Item_in_subselect::val_real()
   */
   DBUG_ASSERT(0);
   DBUG_ASSERT(fixed == 1);
-  null_value= 0;
+  null_value= was_null= FALSE;
   if (exec())
   {
     reset();
-    null_value= 1;
     return 0;
   }
   if (was_null && !value)
-    null_value= 1;
+    null_value= TRUE;
   return (double) value;
 }
 
@@ -1207,15 +1209,14 @@ longlong Item_in_subselect::val_int()
   */
   DBUG_ASSERT(0);
   DBUG_ASSERT(fixed == 1);
-  null_value= 0;
+  null_value= was_null= FALSE;
   if (exec())
   {
     reset();
-    null_value= 1;
     return 0;
   }
   if (was_null && !value)
-    null_value= 1;
+    null_value= TRUE;
   return value;
 }
 
@@ -1228,16 +1229,15 @@ String *Item_in_subselect::val_str(String *str)
   */
   DBUG_ASSERT(0);
   DBUG_ASSERT(fixed == 1);
-  null_value= 0;
+  null_value= was_null= FALSE;
   if (exec())
   {
     reset();
-    null_value= 1;
     return 0;
   }
   if (was_null && !value)
   {
-    null_value= 1;
+    null_value= TRUE;
     return 0;
   }
   str->set((ulonglong)value, &my_charset_bin);
@@ -1248,22 +1248,16 @@ String *Item_in_subselect::val_str(String *str)
 bool Item_in_subselect::val_bool()
 {
   DBUG_ASSERT(fixed == 1);
-  null_value= 0;
+  null_value= was_null= FALSE;
   if (is_constant)
     return value;
   if (exec())
   {
     reset();
-    /* 
-      Must mark the IN predicate as NULL so as to make sure an enclosing NOT
-      predicate will return FALSE. See the comments in 
-      subselect_uniquesubquery_engine::copy_ref_key for further details.
-    */
-    null_value= 1;
     return 0;
   }
   if (was_null && !value)
-    null_value= 1;
+    null_value= TRUE;
   return value;
 }
 
@@ -1274,16 +1268,15 @@ my_decimal *Item_in_subselect::val_decimal(my_decimal *decimal_value)
     method should not be used
   */
   DBUG_ASSERT(0);
-  null_value= 0;
+  null_value= was_null= FALSE;
   DBUG_ASSERT(fixed == 1);
   if (exec())
   {
     reset();
-    null_value= 1;
     return 0;
   }
   if (was_null && !value)
-    null_value= 1;
+    null_value= TRUE;
   int2my_decimal(E_DEC_FATAL_ERROR, value, 0, decimal_value);
   return decimal_value;
 }
@@ -2650,19 +2643,28 @@ int subselect_single_select_engine::exec()
       DBUG_RETURN(join->error ? join->error : 1);
     }
     if (!select_lex->uncacheable && thd->lex->describe && 
-        !(join->select_options & SELECT_DESCRIBE) && 
-        join->need_tmp && item->const_item())
+        !(join->select_options & SELECT_DESCRIBE))
     {
-      /*
-        Force join->join_tmp creation, because this subquery will be replaced
-        by a simple select from the materialization temp table by optimize()
-        called by EXPLAIN and we need to preserve the initial query structure
-        so we can display it.
-       */
-      select_lex->uncacheable|= UNCACHEABLE_EXPLAIN;
-      select_lex->master_unit()->uncacheable|= UNCACHEABLE_EXPLAIN;
-      if (join->init_save_join_tab())
-        DBUG_RETURN(1);                        /* purecov: inspected */
+      item->update_used_tables();
+      if (item->const_item())
+      {
+        /*
+          It's necessary to keep original JOIN table because
+          create_sort_index() function may overwrite original
+          JOIN_TAB::type and wrong optimization method can be
+          selected on re-execution.
+        */
+        select_lex->uncacheable|= UNCACHEABLE_EXPLAIN;
+        select_lex->master_unit()->uncacheable|= UNCACHEABLE_EXPLAIN;
+        /*
+          Force join->join_tmp creation, because this subquery will be replaced
+          by a simple select from the materialization temp table by optimize()
+          called by EXPLAIN and we need to preserve the initial query structure
+          so we can display it.
+        */
+        if (join->need_tmp && join->init_save_join_tab())
+          DBUG_RETURN(1);                        /* purecov: inspected */
+      }
     }
     if (item->engine_changed)
     {