bzr push into mysql-5.1 branch (gshchepa:2702 to 2703) Bug#37997, Bug#37761

[Gleb Shchepa]

 2703 Gleb Shchepa	2008-07-14
      Bug #37761: IN handles NULL differently for table-subquery 
                  and value-list
      
      The server returns unexpected results if a right side of the 
      NOT IN clause consists of NULL value and some constants of
      the same type, for example:
      
        SELECT * FROM t WHERE NOT t.id IN (NULL, 1, 2) 
        
      may return 3, 4, 5 etc if a table contains these values.
      
      
      The Item_func_in::val_int method has been modified:
      unnecessary resets of an Item_func_case::has_null field 
      value has been moved outside of an argument comparison
      loop. (Also unnecessary re-initialization of the null_value
      field has been moved).
modified:
  mysql-test/r/func_in.result
  mysql-test/t/func_in.test
  sql/item_cmpfunc.cc

 2702 Horst Hunger	2008-07-11 [merge]
      Fix of Bug#37997. Polling until disconnect is not more in the processlist
modified:
  mysql-test/r/max_user_connections_func.result
  mysql-test/t/max_user_connections_func.test

=== modified file 'mysql-test/r/func_in.result'
--- a/mysql-test/r/func_in.result	2008-02-12 19:09:16 +0000
+++ b/mysql-test/r/func_in.result	2008-07-14 09:06:49 +0000
@@ -569,4 +569,10 @@ insert into t1 values (),(),(),(),(),(),
 select a from t1 where a not in (a,a,a) group by a;
 a
 drop table t1;
+create table t1 (id int);
+select * from t1 where NOT id in (select null union all select 1);
+id
+select * from t1 where NOT id in (null, 1);
+id
+drop table t1;
 End of 5.1 tests

=== modified file 'mysql-test/t/func_in.test'
--- a/mysql-test/t/func_in.test	2007-10-31 21:24:32 +0000
+++ b/mysql-test/t/func_in.test	2008-07-14 09:06:49 +0000
@@ -417,4 +417,13 @@ insert into t1 values (),(),(),(),(),(),
 select a from t1 where a not in (a,a,a) group by a;
 drop table t1;
 
+#
+# Bug #37761: IN handles NULL differently for table-subquery and value-list
+#
+
+create table t1 (id int);
+select * from t1 where NOT id in (select null union all select 1);
+select * from t1 where NOT id in (null, 1);
+drop table t1;
+
 --echo End of 5.1 tests

=== modified file 'sql/item_cmpfunc.cc'
--- a/sql/item_cmpfunc.cc	2008-03-28 18:20:21 +0000
+++ b/sql/item_cmpfunc.cc	2008-07-14 09:06:49 +0000
@@ -3758,6 +3758,9 @@ longlong Item_func_in::val_int()
     return (longlong) (!null_value && tmp != negated);
   }
 
+  if ((null_value= args[0]->null_value))
+    return 0;
+  have_null= 0;
   for (uint i= 1 ; i < arg_count ; i++)
   {
     Item_result cmp_type= item_cmp_type(left_result_type, args[i]->result_type());
@@ -3766,9 +3769,6 @@ longlong Item_func_in::val_int()
     if (!(value_added_map & (1 << (uint)cmp_type)))
     {
       in_item->store_value(args[0]);
-      if ((null_value=args[0]->null_value))
-        return 0;
-      have_null= 0;
       value_added_map|= 1 << (uint)cmp_type;
     }
     if (!in_item->cmp(args[i]) && !args[i]->null_value)