diff --git a/mysql-test/r/derived.result b/mysql-test/r/derived.result
index d0f42c3d3ec..7c44466ae92 100644
--- a/mysql-test/r/derived.result
+++ b/mysql-test/r/derived.result
@@ -568,3 +568,15 @@ update t1 set balance=(select sum(balance) from (SELECT balance FROM t1 where ac
set optimizer_switch=@save_derived_optimizer_switch_bug;
drop table t1;
set optimizer_switch=@save_derived_optimizer_switch;
+#
+# MDEV-6892: WHERE does not apply
+#
+create table t1 (id int);
+create table t2 (id int);
+insert into t1 values(1),(2),(3);
+insert into t2 values(4),(5),(6);
+select x.id, message from (select id from t1) x left join
+(select id, 1 as message from t2) y on x.id=y.id
+where coalesce(message,0) <> 0;
+id message
+drop table t1,t2;
diff --git a/mysql-test/t/derived.test b/mysql-test/t/derived.test
index 61ae3695a1f..ddce7f55292 100644
--- a/mysql-test/t/derived.test
+++ b/mysql-test/t/derived.test
@@ -492,5 +492,17 @@ update t1 set balance=(select sum(balance) from (SELECT balance FROM t1 where ac
set optimizer_switch=@save_derived_optimizer_switch_bug;
drop table t1;
-
set optimizer_switch=@save_derived_optimizer_switch;
+
+--echo #
+--echo # MDEV-6892: WHERE does not apply
+--echo #
+create table t1 (id int);
+create table t2 (id int);
+insert into t1 values(1),(2),(3);
+insert into t2 values(4),(5),(6);
+#explain extended
+select x.id, message from (select id from t1) x left join
+(select id, 1 as message from t2) y on x.id=y.id
+where coalesce(message,0) <> 0;
+drop table t1,t2;
diff --git a/sql/item.cc b/sql/item.cc
index cfc5f67dc8e..59ec3e69102 100644
--- a/sql/item.cc
+++ b/sql/item.cc
@@ -7949,6 +7949,7 @@ bool Item_direct_view_ref::fix_fields(THD *thd, Item **reference)
return TRUE;
if (view->table && view->table->maybe_null)
maybe_null= TRUE;
+ set_null_ref_table();
return FALSE;
}
@@ -9790,13 +9791,28 @@ void Item_ref::update_used_tables()
(*ref)->update_used_tables();
}
+void Item_direct_view_ref::update_used_tables()
+{
+ set_null_ref_table();
+ Item_direct_ref::update_used_tables();
+}
+
+
table_map Item_direct_view_ref::used_tables() const
{
- return get_depended_from() ?
- OUTER_REF_TABLE_BIT :
- ((view->is_merged_derived() || view->merged || !view->table) ?
- (*ref)->used_tables() :
- view->table->map);
+ DBUG_ASSERT(null_ref_table);
+
+ if (get_depended_from())
+ return OUTER_REF_TABLE_BIT;
+
+ if (view->is_merged_derived() || view->merged || !view->table)
+ return ((*ref)->used_tables() ?
+ (*ref)->used_tables() :
+ ((null_ref_table != NO_NULL_TABLE) ?
+ null_ref_table->map :
+ (table_map)0 ));
+
+ return view->table->map;
}
table_map Item_direct_view_ref::not_null_tables() const
diff --git a/sql/item.h b/sql/item.h
index ed50605ef7b..2d7236615a8 100644
--- a/sql/item.h
+++ b/sql/item.h
@@ -3315,13 +3315,16 @@ class Item_direct_view_ref :public Item_direct_ref
#define NO_NULL_TABLE (reinterpret_cast
(0x1))
+ void set_null_ref_table()
+ {
+ if (!view->is_inner_table_of_outer_join() ||
+ !(null_ref_table= view->get_real_join_table()))
+ null_ref_table= NO_NULL_TABLE;
+ }
+
bool check_null_ref()
{
- if (null_ref_table == NULL)
- {
- if (!(null_ref_table= view->get_real_join_table()))
- null_ref_table= NO_NULL_TABLE;
- }
+ DBUG_ASSERT(null_ref_table);
if (null_ref_table != NO_NULL_TABLE && null_ref_table->null_row)
{
null_value= 1;
@@ -3329,6 +3332,7 @@ class Item_direct_view_ref :public Item_direct_ref
}
return FALSE;
}
+
public:
Item_direct_view_ref(Name_resolution_context *context_arg, Item **item,
const char *table_name_arg,
@@ -3336,7 +3340,11 @@ public:
TABLE_LIST *view_arg)
:Item_direct_ref(context_arg, item, table_name_arg, field_name_arg),
item_equal(0), view(view_arg),
- null_ref_table(NULL) {}
+ null_ref_table(NULL)
+ {
+ if (fixed)
+ set_null_ref_table();
+ }
bool fix_fields(THD *, Item **);
bool eq(const Item *item, bool binary_cmp) const;
@@ -3353,8 +3361,10 @@ public:
bool subst_argument_checker(uchar **arg);
Item *equal_fields_propagator(uchar *arg);
Item *replace_equal_field(uchar *arg);
- table_map used_tables() const;
+ table_map used_tables() const;
+ void update_used_tables();
table_map not_null_tables() const;
+ bool const_item() const { return used_tables() == 0; }
bool walk(Item_processor processor, bool walk_subquery, uchar *arg)
{
return (*ref)->walk(processor, walk_subquery, arg) ||
diff --git a/sql/table.cc b/sql/table.cc
index 7df2ae641ca..e4dee77171d 100644
--- a/sql/table.cc
+++ b/sql/table.cc
@@ -5034,7 +5034,8 @@ 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)
+ if ((tbl->view == NULL && tbl->derived == NULL) ||
+ tbl->is_materialized_derived())
break;
/* we do not support merging of union yet */
DBUG_ASSERT(tbl->view == NULL ||
@@ -5043,28 +5044,25 @@ TABLE *TABLE_LIST::get_real_join_table()
tbl->derived->first_select()->next_select() == NULL);
{
- List_iterator_fast ti;
+ List_iterator_fast
+ ti(tbl->view != NULL ?
+ tbl->view->select_lex.top_join_list :
+ tbl->derived->first_select()->top_join_list);
+ for (;;)
{
- List_iterator_fast
- ti(tbl->view != NULL ?
- tbl->view->select_lex.top_join_list :
- tbl->derived->first_select()->top_join_list);
- for (;;)
- {
- tbl= NULL;
- /*
- Find left table in outer join on this level
- (the list is reverted).
- */
- for (TABLE_LIST *t= ti++; t; t= ti++)
- tbl= t;
- if (!tbl)
- return NULL; // view/derived with no tables
- if (!tbl->nested_join)
- break;
- /* go deeper if we've found nested join */
- ti= tbl->nested_join->join_list;
- }
+ tbl= NULL;
+ /*
+ Find left table in outer join on this level
+ (the list is reverted).
+ */
+ for (TABLE_LIST *t= ti++; t; t= ti++)
+ tbl= t;
+ if (!tbl)
+ return NULL; // view/derived with no tables
+ if (!tbl->nested_join)
+ break;
+ /* go deeper if we've found nested join */
+ ti= tbl->nested_join->join_list;
}
}
}