diff --git a/mysql-test/r/union.result b/mysql-test/r/union.result
index e23b1c8a326..a63358ff2bc 100644
--- a/mysql-test/r/union.result
+++ b/mysql-test/r/union.result
@@ -872,6 +872,22 @@ count(*)
 show status like 'Slow_queries';
 Variable_name	Value
 Slow_queries	7
+flush status;
+select a from t1 where b not in (1,2,3) union select a from t1 where b not in (4,5,6);
+a
+4
+5
+3
+6
+7
+8
+9
+10
+1
+2
+show status like 'Slow_queries';
+Variable_name	Value
+Slow_queries	1
 drop table t1;
 create table t1 (   RID int(11) not null default '0',   IID int(11) not null default '0',    nada varchar(50)  not null,NAME varchar(50) not null,PHONE varchar(50) not null) engine=MyISAM;
 insert into t1 ( RID,IID,nada,NAME,PHONE) values (1, 1, 'main', 'a', '111'), (2, 1, 'main', 'b', '222'), (3, 1, 'main', 'c', '333'), (4, 1, 'main', 'd', '444'), (5, 1, 'main', 'e', '555'), (6, 2, 'main', 'c', '333'), (7, 2, 'main', 'd', '454'), (8, 2, 'main', 'e', '555'), (9, 2, 'main', 'f', '666'), (10, 2, 'main', 'g', '777');
diff --git a/mysql-test/t/union.test b/mysql-test/t/union.test
index 58e4c22e168..6045d8e3c30 100644
--- a/mysql-test/t/union.test
+++ b/mysql-test/t/union.test
@@ -499,6 +499,10 @@ select count(*) from t1 where b=13 union select count(*) from t1 where a=7;
 show status like 'Slow_queries';
 select count(*) from t1 where a=7 union select count(*) from t1 where b=13;
 show status like 'Slow_queries';
+# additional test for examined rows
+flush status;
+select a from t1 where b not in (1,2,3) union select a from t1 where b not in (4,5,6); 
+show status like 'Slow_queries';
 drop table t1;
 
 #
diff --git a/sql/sql_union.cc b/sql/sql_union.cc
index ce84be47243..0a91eb4c0e1 100644
--- a/sql/sql_union.cc
+++ b/sql/sql_union.cc
@@ -478,11 +478,14 @@ bool st_select_lex_unit::exec()
 	}
 	res= sl->join->error;
 	offset_limit_cnt= sl->offset_limit;
-	if (!res && union_result->flush())
+	if (!res)
 	{
-          examined_rows+= thd->examined_row_count;
-	  thd->lex->current_select= lex_select_save;
-	  DBUG_RETURN(TRUE);
+	  examined_rows+= thd->examined_row_count;
+	  if (union_result->flush())
+	  {
+	    thd->lex->current_select= lex_select_save;
+	    DBUG_RETURN(1);
+	  }
 	}
       }
       if (res)