MDEV-486 LP BUG#1010116 fix.

Link view/derived table fields to a real table to check turning the table record to null row.

Item_direct_view_ref wrapper now checks if table is turned to null row.

mysql-test/r/derived_view.result

@@ -1677,7 +1677,6 @@ SELECT t.b, t.c, t1.a
 FROM t1, (SELECT t2.b, t2.c FROM t3 RIGHT JOIN t2 ON t2.a = t3.b) AS t
 WHERE t.b AND t.c = t1.a;
 b	c	a
-8	c	c
 EXPLAIN EXTENDED
 SELECT t.b, t.c, t1.a
 FROM t1, (SELECT t2.b, t2.c FROM t3 RIGHT JOIN t2 ON t2.a = t3.b) AS t
@@ -1692,7 +1691,6 @@ SELECT t.b, t.c, t1.a
 FROM t1, (SELECT t2.b, t2.c FROM t3 RIGHT JOIN t2 ON t2.a = t3.b) AS t
 WHERE t.b <> 0 AND t.c = t1.a;
 b	c	a
-8	c	c
 INSERT INTO t3 VALUES (100), (200);
 EXPLAIN EXTENDED
 SELECT t.b, t.c, t1.a
@@ -1708,7 +1706,7 @@ SELECT t.b, t.c, t1.a
 FROM t1, (SELECT t2.b, t2.c FROM t3 RIGHT JOIN t2 ON t2.a = t3.b) AS t
 WHERE t.b AND t.c = t1.a;
 b	c	a
-8	c	c
+NULL	NULL	c
 EXPLAIN EXTENDED
 SELECT t.b, t.c, t1.a
 FROM t1, (SELECT t2.b, t2.c FROM t3 RIGHT JOIN t2 ON t2.a = t3.b) AS t
@@ -1723,7 +1721,7 @@ SELECT t.b, t.c, t1.a
 FROM t1, (SELECT t2.b, t2.c FROM t3 RIGHT JOIN t2 ON t2.a = t3.b) AS t
 WHERE t.b <> 0 AND t.c = t1.a;
 b	c	a
-8	c	c
+NULL	NULL	c
 SET optimizer_switch=@save_optimizer_switch;
 DROP TABLE t1,t2,t3;
 #

mysql-test/r/view.result

@@ -4485,6 +4485,39 @@ a
 1
 drop view v2,v1;
 drop table t1;
+#
+# MDEV-486 LP BUG#1010116 Incorrect query results in
+# view and derived tables
+#
+SELECT
+`Derived1`.`id`,
+`Derived2`.`Val1`
+FROM (select 30631 as `id`) AS `Derived1` LEFT OUTER JOIN (SELECT
+2 as `id`,
+1 AS `Val1`
+FROM (select 30631 as `id`) AS `Derived3`) AS `Derived2` ON `Derived1`.`id` = `Derived2`.`id`;
+id	Val1
+30631	NULL
+create table t1 ( id int );
+insert into t1 values (30631);
+create table t2 ( id int );
+insert into t2 values (30631);
+create algorithm=MERGE view v2 as select 2 as id, 1 as val1 from t2;
+select t1.*, v2.* from t1 left join v2 on t1.id = v2.id;
+id	id	val1
+30631	NULL	NULL
+drop view v2;
+drop table t1,t2;
+create table t1 ( id int );
+insert into t1 values (30631);
+create table t2 ( id int );
+insert into t2 values (30631);
+create algorithm=MERGE view v2 as select 2 as id, id is null as bbb, id as iddqd, 1 as val1 from t2;
+select t1.*, v2.* from t1 left join v2 on t1.id = v2.id;
+id	id	bbb	iddqd	val1
+30631	NULL	NULL	NULL	NULL
+drop view v2;
+drop table t1,t2;
 # -----------------------------------------------------------------
 # -- End of 5.3 tests.
 # -----------------------------------------------------------------

mysql-test/t/view.test

@@ -4433,6 +4433,36 @@ select * from t1;
 drop view v2,v1;
 drop table t1;
 
+--echo #
+--echo # MDEV-486 LP BUG#1010116 Incorrect query results in
+--echo # view and derived tables
+--echo #
+
+SELECT
+`Derived1`.`id`,
+`Derived2`.`Val1`
+FROM (select 30631 as `id`) AS `Derived1` LEFT OUTER JOIN (SELECT
+2 as `id`,
+1 AS `Val1`
+FROM (select 30631 as `id`) AS `Derived3`) AS `Derived2` ON `Derived1`.`id` = `Derived2`.`id`;
+
+create table t1 ( id int );
+insert into t1 values (30631);
+create table t2 ( id int );
+insert into t2 values (30631);
+create algorithm=MERGE view v2 as select 2 as id, 1 as val1 from t2;
+select t1.*, v2.* from t1 left join v2 on t1.id = v2.id;
+drop view v2;
+drop table t1,t2;
+
+create table t1 ( id int );
+insert into t1 values (30631);
+create table t2 ( id int );
+insert into t2 values (30631);
+create algorithm=MERGE view v2 as select 2 as id, id is null as bbb, id as iddqd, 1 as val1 from t2;
+select t1.*, v2.* from t1 left join v2 on t1.id = v2.id;
+drop view v2;
+drop table t1,t2;
 --echo # -----------------------------------------------------------------
 --echo # -- End of 5.3 tests.
 --echo # -----------------------------------------------------------------

sql/item.cc

@@ -7339,6 +7339,7 @@ Item* Item_cache_wrapper::get_tmp_table_item(THD *thd_arg)
 
 bool Item_direct_view_ref::fix_fields(THD *thd, Item **reference)
 {
+  DBUG_ASSERT(1);
   /* view fild reference must be defined */
   DBUG_ASSERT(*ref);
   /* (*ref)->check_cols() will be made in Item_direct_ref::fix_fields */

sql/item.h

@@ -2925,20 +2925,29 @@ class Item_direct_view_ref :public Item_direct_ref
 {
   Item_equal *item_equal;
   TABLE_LIST *view;
+  TABLE *null_ref_table;
+
+  bool check_null_ref()
+  {
+    if (null_ref_table == NULL)
+    {
+      null_ref_table= view->get_real_join_table();
+    }
+    if (null_ref_table->null_row)
+    {
+      null_value= 1;
+      return TRUE;
+    }
+    return FALSE;
+  }
 public:
   Item_direct_view_ref(Name_resolution_context *context_arg, Item **item,
                        const char *table_name_arg,
                        const char *field_name_arg,
                        TABLE_LIST *view_arg)
     :Item_direct_ref(context_arg, item, table_name_arg, field_name_arg),
-    item_equal(0), view(view_arg) {}
-  /* Constructor need to process subselect with temporary tables (see Item) */
-  Item_direct_view_ref(THD *thd, Item_direct_ref *item)
-    :Item_direct_ref(thd, item), item_equal(0) {}
-  Item_direct_view_ref(TABLE_LIST *view_arg, Item **item,
-                       const char *field_name_arg)
-    :Item_direct_ref(view_arg, item, field_name_arg), item_equal(0)
-  {}
+    item_equal(0), view(view_arg),
+    null_ref_table(NULL) {}
 
   bool fix_fields(THD *, Item **);
   bool eq(const Item *item, bool binary_cmp) const;
@@ -2969,6 +2978,84 @@ public:
       view_arg->view_used_tables|= (*ref)->used_tables();
     return 0;
   }
+  void save_val(Field *to)
+  {
+    if (check_null_ref())
+      to->set_null();
+    else
+      Item_direct_ref::save_val(to);
+  }
+  double val_real()
+  {
+    if (check_null_ref())
+      return 0;
+    else
+      return Item_direct_ref::val_real();
+  }
+  longlong val_int()
+  {
+    if (check_null_ref())
+      return 0;
+    else
+      return Item_direct_ref::val_int();
+  }
+  String *val_str(String* tmp)
+  {
+    if (check_null_ref())
+      return NULL;
+    else
+      return Item_direct_ref::val_str(tmp);
+  }
+  my_decimal *val_decimal(my_decimal *tmp)
+  {
+    if (check_null_ref())
+      return NULL;
+    else
+      return Item_direct_ref::val_decimal(tmp);
+  }
+  bool val_bool()
+  {
+    if (check_null_ref())
+      return 0;
+    else
+      return Item_direct_ref::val_bool();
+  }
+  bool is_null()
+  {
+    if (check_null_ref())
+      return 1;
+    else
+      return Item_direct_ref::is_null();
+  }
+  bool get_date(MYSQL_TIME *ltime, uint fuzzydate)
+  {
+    if (check_null_ref())
+    {
+      bzero((char*) ltime,sizeof(*ltime));
+      return 1;
+    }
+    return Item_direct_ref::get_date(ltime, fuzzydate);
+  }
+  bool send(Protocol *protocol, String *buffer)
+  {
+    if (check_null_ref())
+      return protocol->store_null();
+    return Item_direct_ref::send(protocol, buffer);
+  }
+  void save_org_in_field(Field *field)
+  {
+    if (check_null_ref())
+      field->set_null();
+    else
+      Item_direct_ref::save_val(field);
+  }
+  void save_in_result_field(bool no_conversions)
+  {
+    if (check_null_ref())
+      result_field->set_null();
+    else
+      Item_direct_ref::save_in_result_field(no_conversions);
+  }
 };
 
 

sql/table.cc

@@ -4441,6 +4441,28 @@ void TABLE_LIST::set_check_materialized()
   }
 }
 
+TABLE *TABLE_LIST::get_real_join_table()
+{
+  TABLE_LIST *tbl= this;
+  while (tbl->table == NULL || tbl->table->reginfo.join_tab == NULL)
+  {
+    if (tbl->view == NULL && tbl->derived == NULL)
+      break;
+    /* we do not support merging of union yet */
+    DBUG_ASSERT(tbl->view == NULL ||
+               tbl->view->select_lex.next_select() == NULL);
+    DBUG_ASSERT(tbl->derived == NULL ||
+               tbl->derived->first_select()->next_select() == NULL);
+
+    if (tbl->table)
+      table= tbl->table;
+    tbl= (tbl->view != NULL ?
+          tbl->view->select_lex.get_table_list() :
+          tbl->derived->first_select()->get_table_list());
+  }
+  return tbl->table;
+}
+
 
 Natural_join_column::Natural_join_column(Field_translator *field_param,
                                          TABLE_LIST *tab)

sql/table.h

@@ -1671,6 +1671,7 @@ struct TABLE_LIST
   TABLE_LIST *find_underlying_table(TABLE *table);
   TABLE_LIST *first_leaf_for_name_resolution();
   TABLE_LIST *last_leaf_for_name_resolution();
+  TABLE *get_real_join_table();
   bool is_leaf_for_name_resolution();
   inline TABLE_LIST *top_table()
     { return belong_to_view ? belong_to_view : this; }