Merge branch '10.0' into 10.1

1 files changed, 33 insertions, 30 deletions

diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index e56f301af86..c52f74fbd4a 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -1250,10 +1250,19 @@ JOIN::optimize_inner()
     if (cond_value == Item::COND_FALSE || having_value == Item::COND_FALSE || 
         (!unit->select_limit_cnt && !(select_options & OPTION_FOUND_ROWS)))
     {						/* Impossible cond */
-      DBUG_PRINT("info", (having_value == Item::COND_FALSE ? 
-                            "Impossible HAVING" : "Impossible WHERE"));
-      zero_result_cause=  having_value == Item::COND_FALSE ?
-                           "Impossible HAVING" : "Impossible WHERE";
+      if (unit->select_limit_cnt)
+      {
+        DBUG_PRINT("info", (having_value == Item::COND_FALSE ?
+                              "Impossible HAVING" : "Impossible WHERE"));
+        zero_result_cause=  having_value == Item::COND_FALSE ?
+                             "Impossible HAVING" : "Impossible WHERE";
+      }
+      else
+      {
+        DBUG_PRINT("info", ("Zero limit"));
+        zero_result_cause= "Zero limit";
+        conds= 0;
+      }
       table_count= top_join_tab_count= 0;
       error= 0;
       goto setup_subq_exit;
@@ -25465,21 +25474,18 @@ void JOIN::set_allowed_join_cache_types()
 
 void JOIN::save_query_plan(Join_plan_state *save_to)
 {
-  if (keyuse.elements)
-  {
-    DYNAMIC_ARRAY tmp_keyuse;
-    /* Swap the current and the backup keyuse internal arrays. */
-    tmp_keyuse= keyuse;
-    keyuse= save_to->keyuse; /* keyuse is reset to an empty array. */
-    save_to->keyuse= tmp_keyuse;
+  DYNAMIC_ARRAY tmp_keyuse;
+  /* Swap the current and the backup keyuse internal arrays. */
+  tmp_keyuse= keyuse;
+  keyuse= save_to->keyuse; /* keyuse is reset to an empty array. */
+  save_to->keyuse= tmp_keyuse;
 
-    for (uint i= 0; i < table_count; i++)
-    {
-      save_to->join_tab_keyuse[i]= join_tab[i].keyuse;
-      join_tab[i].keyuse= NULL;
-      save_to->join_tab_checked_keys[i]= join_tab[i].checked_keys;
-      join_tab[i].checked_keys.clear_all();
-    }
+  for (uint i= 0; i < table_count; i++)
+  {
+    save_to->join_tab_keyuse[i]= join_tab[i].keyuse;
+    join_tab[i].keyuse= NULL;
+    save_to->join_tab_checked_keys[i]= join_tab[i].checked_keys;
+    join_tab[i].checked_keys.clear_all();
   }
   memcpy((uchar*) save_to->best_positions, (uchar*) best_positions,
          sizeof(POSITION) * (table_count + 1));
@@ -25517,20 +25523,17 @@ void JOIN::reset_query_plan()
 
 void JOIN::restore_query_plan(Join_plan_state *restore_from)
 {
-  if (restore_from->keyuse.elements)
-  {
-    DYNAMIC_ARRAY tmp_keyuse;
-    tmp_keyuse= keyuse;
-    keyuse= restore_from->keyuse;
-    restore_from->keyuse= tmp_keyuse;
-
-    for (uint i= 0; i < table_count; i++)
-    {
-      join_tab[i].keyuse= restore_from->join_tab_keyuse[i];
-      join_tab[i].checked_keys= restore_from->join_tab_checked_keys[i];
-    }
+  DYNAMIC_ARRAY tmp_keyuse;
+  tmp_keyuse= keyuse;
+  keyuse= restore_from->keyuse;
+  restore_from->keyuse= tmp_keyuse;
 
+  for (uint i= 0; i < table_count; i++)
+  {
+    join_tab[i].keyuse= restore_from->join_tab_keyuse[i];
+    join_tab[i].checked_keys= restore_from->join_tab_checked_keys[i];
   }
+
   memcpy((uchar*) best_positions, (uchar*) restore_from->best_positions,
          sizeof(POSITION) * (table_count + 1));
   /* Restore SJM nests */