Fixed MDEV-14883 Usage of EXCEPT and INTERSECT in recursive CTE

is not supported

Allowed to use recursive references in derived tables.
As a result usage of recursive references in operands of
INTERSECT / EXCEPT is now supported.

9 files changed, 464 insertions, 22 deletions

diff --git a/mysql-test/r/cte_recursive.result b/mysql-test/r/cte_recursive.result
index dd0f1e91cb7..15d4fc1a01f 100644
--- a/mysql-test/r/cte_recursive.result
+++ b/mysql-test/r/cte_recursive.result
@@ -3105,3 +3105,236 @@ SELECT * FROM cte;
 5
 2
 3
+#
+# MDEV-14883: recursive references in operands of INTERSECT / EXCEPT
+#
+create table flights
+(departure varchar(32),
+arrival varchar(32),
+carrier varchar(20),
+flight_number char(7));
+insert into flights values
+('Seattle', 'Frankfurt', 'Lufthansa', 'LH 491'),
+('Seattle', 'Amsterdam', 'KLM', 'KL 6032'),
+('Seattle', 'Chicago', 'American', 'AA 2573'),
+('Seattle', 'Los Angeles', 'Alaska Air', 'AS 410'),
+('Chicago', 'New York', 'American', 'AA 375'),
+('Chicago', 'Montreal', 'Air Canada', 'AC 3053'),
+('Los Angeles', 'New York', 'Delta', 'DL 1197'),
+('New York', 'London', 'British Airways', 'BA 1511'),
+('London', 'Moscow', 'British Airways', 'BA 233'),
+('Moscow', 'Tokyo', 'Aeroflot', 'SU 264'),
+('Moscow', 'Dubai', 'Emirates', 'EK 2421'),
+('Dubai', 'Tokyo', 'Emirates', 'EK 318'),
+('Dubai', 'Bangkok', 'Emirates', 'EK 2142'),
+('Beijing', 'Bangkok', 'Air China', 'CA 757'),
+('Beijing', 'Tokyo', 'Air China', 'CA 6653'),
+('Moscow', 'Bangkok', 'Aeroflot', 'SU 270'),
+('New York', 'Reykjavik', 'Icelandair', 'FL 416'),
+('New York', 'Paris', 'Air France', 'AF 23'),
+('Amsterdam', 'Moscow', 'KLM', 'KL 903'),
+('Frankfurt', 'Dubai', 'Lufthansa', 'LH 630'),
+('Frankfurt', 'Moscow', 'Lufthansa', 'LH 1444'),
+('Reykjavik', 'London', 'British Airways', 'BA 2229'),
+('Frankfurt', 'Beijing', 'Air China', 'CA 966'),
+('Tokyo', 'Seattle', 'ANA', 'NH 178'),
+('Los Angeles', 'Tokyo', 'ANA', 'NH 175'),
+('Moscow', 'Los Angeles', 'Aeroflot', 'SU 106'),
+('Montreal', 'Paris', 'Air Canada', 'AC 870'),
+('London', 'Delhi', 'British Airways', 'BA 143'),
+('Delhi', 'Bangkok', 'Air India', 'AI 306'),
+('Delhi', 'Dubai', 'Air India', 'AI 995'),
+('Dubai', 'Cairo', 'Emirates', 'EK 927'),
+('Cairo', 'Paris', 'Air France', 'AF 503'),
+('Amsterdam', 'New York', 'Delta', 'DL 47'),
+('New York', 'Seattle', 'American', 'AA 45'),
+('Paris', 'Chicago', 'Air France', 'AF 6734');
+create table distances
+(city1 varchar(32),
+city2 varchar(32),
+dist int);
+insert into distances values
+('Seattle', 'Frankfurt', 5080),
+('Seattle', 'Amsterdam', 4859),
+('Seattle', 'Chicago', 1733),
+('Seattle', 'Los Angeles', 960),
+('Chicago', 'New York', 712),
+('Chicago', 'Montreal', 746),
+('Los Angeles', 'New York', 2446),
+('New York', 'London', 3459),
+('London', 'Moscow', 1554),
+('Moscow', 'Tokyo', 4647),
+('Moscow', 'Dubai', 2298),
+('Dubai', 'Tokyo', 4929),
+('Dubai', 'Bangkok', 3050),
+('Beijing', 'Bangkok', 2046),
+('Beijing', 'Tokyo', 1301),
+('Moscow', 'Bangkok', 4390),
+('New York', 'Reykjavik', 2613),
+('New York', 'Paris', 3625),
+('Amsterdam', 'Moscow', 1334),
+('Frankfurt', 'Dubai', 3003),
+('Frankfurt', 'Moscow', 1256),
+('Reykjavik', 'London', 1173),
+('Frankfurt', 'Beijing', 4836),
+('Tokyo', 'Seattle', 4783),
+('Los Angeles', 'Tokyo', 5479),
+('Moscow', 'Los Angeles', 6071),
+('Moscow', 'Reykjavik', 2052),
+('Montreal', 'Paris', 3425),
+('London', 'Delhi', 4159),
+('London', 'Paris', 214),
+('Delhi', 'Bangkok', 1810),
+('Delhi', 'Dubai', 1369),
+('Delhi', 'Beijing', 2350),
+('Dubai', 'Cairo', 1501),
+('Cairo', 'Paris', 1992),
+('Amsterdam', 'New York', 3643),
+('New York', 'Seattle', 2402),
+('Paris', 'Chicago', 4136),
+('Paris', 'Los Angeles', 5647);
+with recursive destinations (city) as
+(
+select a.arrival from flights a where a.departure = 'Seattle'
+  union
+select b.arrival from destinations r, flights b where r.city = b.departure
+)
+select * from destinations;
+city
+Frankfurt
+Amsterdam
+Chicago
+Los Angeles
+New York
+Montreal
+Moscow
+Dubai
+Beijing
+Tokyo
+London
+Bangkok
+Reykjavik
+Paris
+Seattle
+Cairo
+Delhi
+with recursive destinations (city) as
+(
+select a.arrival from flights a, distances d
+where a.departure = 'Seattle' and
+a.departure = d.city1 and a.arrival = d.city2 and
+d.dist < 4000
+union
+select b.arrival from destinations r, flights b, distances d
+where r.city = b.departure and
+b.departure = d.city1 and b.arrival = d.city2 and
+d.dist < 4000
+)
+select * from destinations;
+city
+Chicago
+Los Angeles
+New York
+Montreal
+London
+Reykjavik
+Paris
+Seattle
+Moscow
+Dubai
+Bangkok
+Cairo
+set standard_compliant_cte=0;
+with recursive legs_to_destinations
+(departure, arrival, dist, leg_no, acc_mileage) as
+(
+select a.departure, a.arrival, d.dist, 1, d.dist
+from flights a, distances d
+where a.departure = 'Seattle' and
+a.departure = d.city1 and a.arrival = d.city2 and
+d.dist < 4000
+union all
+select b.departure, b.arrival, d.dist, r.leg_no + 1, r.acc_mileage + d.dist
+from legs_to_destinations r, flights b, distances d
+where r.arrival = b.departure and
+b.departure = d.city1 and b.arrival = d.city2 and
+d.dist < 4000 and
+b.arrival not in (select arrival from legs_to_destinations)
+)
+select * from legs_to_destinations;
+departure	arrival	dist	leg_no	acc_mileage
+Seattle	Chicago	1733	1	1733
+Seattle	Los Angeles	960	1	960
+Chicago	New York	712	2	2445
+Chicago	Montreal	746	2	2479
+Los Angeles	New York	2446	2	3406
+New York	London	3459	3	6865
+New York	London	3459	3	5904
+New York	Reykjavik	2613	3	6019
+New York	Reykjavik	2613	3	5058
+New York	Paris	3625	3	7031
+New York	Paris	3625	3	6070
+Montreal	Paris	3425	3	5904
+New York	Seattle	2402	3	5808
+New York	Seattle	2402	3	4847
+London	Moscow	1554	4	7458
+London	Moscow	1554	4	8419
+Moscow	Dubai	2298	5	10717
+Moscow	Dubai	2298	5	9756
+Dubai	Bangkok	3050	6	12806
+Dubai	Bangkok	3050	6	13767
+Dubai	Cairo	1501	6	11257
+Dubai	Cairo	1501	6	12218
+set standard_compliant_cte=default;
+with recursive destinations (city) as
+(
+select a.arrival from flights a, distances d
+where a.departure = 'Seattle' and
+a.departure = d.city1 and a.arrival = d.city2 and
+d.dist < 4000
+union
+select b.arrival from destinations r, flights b
+where r.city = b.departure
+intersect
+select city2 from destinations s, distances d
+where s.city = d.city1 and d.dist < 4000
+)
+select * from destinations;
+city
+Chicago
+Los Angeles
+New York
+Montreal
+London
+Reykjavik
+Paris
+Seattle
+Moscow
+Dubai
+Bangkok
+Cairo
+with recursive destinations (city) as
+(
+select a.arrival from flights a where a.departure = 'Seattle'
+  union
+select * from
+(
+select b.arrival from destinations r, flights b
+where r.city = b.departure
+except
+select arrival from flights
+where arrival in
+('New York', 'London', 'Moscow', 'Dubai', 'Cairo', 'Tokyo')
+) t
+)
+select * from destinations;
+city
+Frankfurt
+Amsterdam
+Chicago
+Los Angeles
+Montreal
+Beijing
+Bangkok
+Paris
+drop table flights, distances;
diff --git a/mysql-test/t/cte_recursive.test b/mysql-test/t/cte_recursive.test
index c6391aabc41..7ed55a1daaa 100644
--- a/mysql-test/t/cte_recursive.test
+++ b/mysql-test/t/cte_recursive.test
@@ -2138,3 +2138,173 @@ WITH RECURSIVE cte AS
 	UNION
 	SELECT @c:=@c+1 FROM cte WHERE @c<3)
 SELECT * FROM cte;
+
+--echo #
+--echo # MDEV-14883: recursive references in operands of INTERSECT / EXCEPT
+--echo #
+
+create table flights
+(departure varchar(32),
+ arrival varchar(32),
+ carrier varchar(20),
+ flight_number char(7));
+
+insert into flights values
+('Seattle', 'Frankfurt', 'Lufthansa', 'LH 491'),
+('Seattle', 'Amsterdam', 'KLM', 'KL 6032'),
+('Seattle', 'Chicago', 'American', 'AA 2573'),
+('Seattle', 'Los Angeles', 'Alaska Air', 'AS 410'),
+('Chicago', 'New York', 'American', 'AA 375'),
+('Chicago', 'Montreal', 'Air Canada', 'AC 3053'),
+('Los Angeles', 'New York', 'Delta', 'DL 1197'),
+('New York', 'London', 'British Airways', 'BA 1511'),
+('London', 'Moscow', 'British Airways', 'BA 233'),
+('Moscow', 'Tokyo', 'Aeroflot', 'SU 264'),
+('Moscow', 'Dubai', 'Emirates', 'EK 2421'),
+('Dubai', 'Tokyo', 'Emirates', 'EK 318'),
+('Dubai', 'Bangkok', 'Emirates', 'EK 2142'),
+('Beijing', 'Bangkok', 'Air China', 'CA 757'),
+('Beijing', 'Tokyo', 'Air China', 'CA 6653'),
+('Moscow', 'Bangkok', 'Aeroflot', 'SU 270'),
+('New York', 'Reykjavik', 'Icelandair', 'FL 416'),
+('New York', 'Paris', 'Air France', 'AF 23'),
+('Amsterdam', 'Moscow', 'KLM', 'KL 903'),
+('Frankfurt', 'Dubai', 'Lufthansa', 'LH 630'),
+('Frankfurt', 'Moscow', 'Lufthansa', 'LH 1444'),
+('Reykjavik', 'London', 'British Airways', 'BA 2229'),
+('Frankfurt', 'Beijing', 'Air China', 'CA 966'),
+('Tokyo', 'Seattle', 'ANA', 'NH 178'),
+('Los Angeles', 'Tokyo', 'ANA', 'NH 175'),
+('Moscow', 'Los Angeles', 'Aeroflot', 'SU 106'),
+('Montreal', 'Paris', 'Air Canada', 'AC 870'),
+('London', 'Delhi', 'British Airways', 'BA 143'),
+('Delhi', 'Bangkok', 'Air India', 'AI 306'),
+('Delhi', 'Dubai', 'Air India', 'AI 995'),
+('Dubai', 'Cairo', 'Emirates', 'EK 927'),
+('Cairo', 'Paris', 'Air France', 'AF 503'),
+('Amsterdam', 'New York', 'Delta', 'DL 47'),
+('New York', 'Seattle', 'American', 'AA 45'),
+('Paris', 'Chicago', 'Air France', 'AF 6734');
+
+create table distances
+(city1 varchar(32),
+ city2 varchar(32),
+ dist int);
+
+insert into distances values
+('Seattle', 'Frankfurt', 5080),
+('Seattle', 'Amsterdam', 4859),
+('Seattle', 'Chicago', 1733),
+('Seattle', 'Los Angeles', 960),
+('Chicago', 'New York', 712),
+('Chicago', 'Montreal', 746),
+('Los Angeles', 'New York', 2446),
+('New York', 'London', 3459),
+('London', 'Moscow', 1554),
+('Moscow', 'Tokyo', 4647),
+('Moscow', 'Dubai', 2298),
+('Dubai', 'Tokyo', 4929),
+('Dubai', 'Bangkok', 3050),
+('Beijing', 'Bangkok', 2046),
+('Beijing', 'Tokyo', 1301),
+('Moscow', 'Bangkok', 4390),
+('New York', 'Reykjavik', 2613),
+('New York', 'Paris', 3625),
+('Amsterdam', 'Moscow', 1334),
+('Frankfurt', 'Dubai', 3003),
+('Frankfurt', 'Moscow', 1256),
+('Reykjavik', 'London', 1173),
+('Frankfurt', 'Beijing', 4836),
+('Tokyo', 'Seattle', 4783),
+('Los Angeles', 'Tokyo', 5479),
+('Moscow', 'Los Angeles', 6071),
+('Moscow', 'Reykjavik', 2052),
+('Montreal', 'Paris', 3425),
+('London', 'Delhi', 4159),
+('London', 'Paris', 214),
+('Delhi', 'Bangkok', 1810),
+('Delhi', 'Dubai', 1369),
+('Delhi', 'Beijing', 2350),
+('Dubai', 'Cairo', 1501),
+('Cairo', 'Paris', 1992),
+('Amsterdam', 'New York', 3643),
+('New York', 'Seattle', 2402),
+('Paris', 'Chicago', 4136),
+('Paris', 'Los Angeles', 5647);
+
+with recursive destinations (city) as
+(
+  select a.arrival from flights a where a.departure = 'Seattle'
+  union
+  select b.arrival from destinations r, flights b where r.city = b.departure
+)
+select * from destinations;
+
+with recursive destinations (city) as
+(
+  select a.arrival from flights a, distances d
+    where a.departure = 'Seattle' and
+          a.departure = d.city1 and a.arrival = d.city2 and
+          d.dist < 4000
+  union
+  select b.arrival from destinations r, flights b, distances d
+    where r.city = b.departure and
+          b.departure = d.city1 and b.arrival = d.city2 and
+          d.dist < 4000
+)
+select * from destinations;
+
+set standard_compliant_cte=0;
+
+with recursive legs_to_destinations
+  (departure, arrival, dist, leg_no, acc_mileage) as
+(
+  select a.departure, a.arrival, d.dist, 1, d.dist
+    from flights a, distances d
+    where a.departure = 'Seattle' and
+          a.departure = d.city1 and a.arrival = d.city2 and
+          d.dist < 4000
+  union all
+  select b.departure, b.arrival, d.dist, r.leg_no + 1, r.acc_mileage + d.dist
+    from legs_to_destinations r, flights b, distances d
+    where r.arrival = b.departure and
+          b.departure = d.city1 and b.arrival = d.city2 and
+          d.dist < 4000 and
+          b.arrival not in (select arrival from legs_to_destinations)
+)
+select * from legs_to_destinations;
+
+set standard_compliant_cte=default;
+
+with recursive destinations (city) as
+(
+  select a.arrival from flights a, distances d
+    where a.departure = 'Seattle' and
+          a.departure = d.city1 and a.arrival = d.city2 and
+          d.dist < 4000
+  union
+  select b.arrival from destinations r, flights b
+    where r.city = b.departure
+  intersect
+  select city2 from destinations s, distances d
+    where s.city = d.city1 and d.dist < 4000
+)
+select * from destinations;
+
+with recursive destinations (city) as
+(
+  select a.arrival from flights a where a.departure = 'Seattle'
+  union
+  select * from
+  (
+    select b.arrival from destinations r, flights b
+      where r.city = b.departure
+    except
+    select arrival from flights
+      where arrival in
+            ('New York', 'London', 'Moscow', 'Dubai', 'Cairo', 'Tokyo')
+  ) t
+)
+select * from destinations;
+
+drop table flights, distances;
diff --git a/sql/sql_cte.cc b/sql/sql_cte.cc
index 05d12998026..61eaa535c00 100644
--- a/sql/sql_cte.cc
+++ b/sql/sql_cte.cc
@@ -1314,32 +1314,29 @@ bool With_element::check_unrestricted_recursive(st_select_lex *sel,
 
 bool st_select_lex::check_subqueries_with_recursive_references()
 {
-  st_select_lex_unit *sl_master= master_unit();
   List_iterator<TABLE_LIST> ti(leaf_tables);
   TABLE_LIST *tbl;
   while ((tbl= ti++))
   {
-    if (!(tbl->is_with_table_recursive_reference() && sl_master->item))
+    if (!(tbl->is_with_table_recursive_reference()))
       continue;
-    With_element *with_elem= tbl->with;
-    bool check_embedding_materialized_derived= true;
+    With_element *rec_elem= tbl->with;
+    st_select_lex_unit *sl_master;
     for (st_select_lex *sl= this; sl; sl= sl_master->outer_select())
-    { 
+    {
       sl_master= sl->master_unit();
-      if (with_elem->get_owner() == sl_master->with_clause)
-         check_embedding_materialized_derived= false;
-      if (check_embedding_materialized_derived && !sl_master->with_element && 
-          sl_master->derived && sl_master->derived->is_materialized_derived())
+      if (sl_master->with_element &&
+          sl_master->with_element->get_owner() == rec_elem->get_owner())
+        break;
+      sl->uncacheable|= UNCACHEABLE_DEPENDENT;
+      sl_master->uncacheable|= UNCACHEABLE_DEPENDENT;
+      if (sl_master->derived)
+        sl_master->derived->register_as_derived_with_rec_ref(rec_elem);
+      if (sl_master->item)
       {
-	my_error(ER_REF_TO_RECURSIVE_WITH_TABLE_IN_DERIVED,
-	  	     MYF(0), with_elem->query_name->str);
-	return true;
+        Item_subselect *subq= (Item_subselect *) (sl_master->item);
+        subq->register_as_with_rec_ref(rec_elem);
       }
-      if (!sl_master->item)
-	continue;
-      Item_subselect *subq= (Item_subselect *) sl_master->item;
-      subq->with_recursive_reference= true;
-      subq->register_as_with_rec_ref(tbl->with);
     }
   }
   return false;
diff --git a/sql/sql_cte.h b/sql/sql_cte.h
index 13e9b83955c..16b473f0665 100644
--- a/sql/sql_cte.h
+++ b/sql/sql_cte.h
@@ -146,7 +146,9 @@ public:
   select_union_recursive *rec_result;
 
   /* List of Item_subselects containing recursive references to this CTE */
-  SQL_I_List<Item_subselect> sq_with_rec_ref; 
+  SQL_I_List<Item_subselect> sq_with_rec_ref;
+  /* List of derived tables containing recursive references to this CTE */
+  SQL_I_List<TABLE_LIST> derived_with_rec_ref;
 
   With_element(LEX_CSTRING *name,
                List <LEX_CSTRING> list,
diff --git a/sql/sql_derived.cc b/sql/sql_derived.cc
index be5058b7c63..ab66384c6cb 100644
--- a/sql/sql_derived.cc
+++ b/sql/sql_derived.cc
@@ -1010,6 +1010,20 @@ bool mysql_derived_create(THD *thd, LEX *lex, TABLE_LIST *derived)
 }
 
 
+void TABLE_LIST::register_as_derived_with_rec_ref(With_element *rec_elem)
+{
+  rec_elem->derived_with_rec_ref.link_in_list(this, &this->next_with_rec_ref);
+  is_derived_with_recursive_reference= true;
+  get_unit()->uncacheable|= UNCACHEABLE_DEPENDENT;
+}
+
+
+bool TABLE_LIST::is_nonrecursive_derived_with_rec_ref()
+{
+  return is_derived_with_recursive_reference;
+}
+
+
 /**
   @brief
     Fill the recursive with table 
diff --git a/sql/sql_select.cc b/sql/sql_select.cc
index a58c34cc2fa..82f332b83df 100644
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -12500,7 +12500,8 @@ bool JOIN_TAB::preread_init()
                                     derived, DT_CREATE | DT_FILL))
       return TRUE;
 
-  if (!(derived->get_unit()->uncacheable & UNCACHEABLE_DEPENDENT))
+  if (!(derived->get_unit()->uncacheable & UNCACHEABLE_DEPENDENT) ||
+      derived->is_nonrecursive_derived_with_rec_ref())
     preread_init_done= TRUE;
   if (select && select->quick)
     select->quick->replace_handler(table->file);
diff --git a/sql/sql_union.cc b/sql/sql_union.cc
index a14c5dd4bd5..857c9a117f5 100644
--- a/sql/sql_union.cc
+++ b/sql/sql_union.cc
@@ -1365,7 +1365,15 @@ bool st_select_lex_unit::exec()
     DBUG_RETURN(saved_error);
 
   if (union_result)
+  {
     union_result->init();
+    if (uncacheable & UNCACHEABLE_DEPENDENT &&
+        union_result->table && union_result->table->is_created())
+    {
+      union_result->table->file->ha_delete_all_rows();
+      union_result->table->file->ha_enable_indexes(HA_KEY_SWITCH_ALL);
+    }
+  }
 
   if (uncacheable || !item || !item->assigned() || describe)
   {
@@ -1663,6 +1671,20 @@ bool st_select_lex_unit::exec_recursive()
    
   for (st_select_lex *sl= start ; sl != end; sl= sl->next_select())
   {
+    if (with_element->level)
+    {
+      for (TABLE_LIST *derived= with_element->derived_with_rec_ref.first;
+           derived;
+           derived= derived->next_with_rec_ref)
+      {
+        if (derived->is_materialized_derived())
+	{
+          if (derived->table->is_created())
+            derived->table->file->ha_delete_all_rows();
+          derived->table->reginfo.join_tab->preread_init_done= false;
+        }
+      }
+    }
     thd->lex->current_select= sl;
     if (sl->tvc)
       sl->tvc->exec(sl);
@@ -1706,7 +1728,7 @@ bool st_select_lex_unit::exec_recursive()
     if (!with_element->rec_result->first_rec_table_to_update)
       with_element->rec_result->first_rec_table_to_update= rec_table;
     if (with_element->level == 1 && rec_table->reginfo.join_tab)
-      rec_table->reginfo.join_tab->preread_init_done= true;  
+      rec_table->reginfo.join_tab->preread_init_done= true;
   }
   for (Item_subselect *sq= with_element->sq_with_rec_ref.first;
        sq;
diff --git a/sql/table.cc b/sql/table.cc
index 549814a57bc..36e92e0e303 100644
--- a/sql/table.cc
+++ b/sql/table.cc
@@ -8371,7 +8371,6 @@ bool TABLE_LIST::is_with_table()
   return derived && derived->with_element;
 }
 
-
 uint TABLE_SHARE::actual_n_key_parts(THD *thd)
 {
   return use_ext_keys &&
diff --git a/sql/table.h b/sql/table.h
index 917439c243d..1977b7fc7e3 100644
--- a/sql/table.h
+++ b/sql/table.h
@@ -2131,7 +2131,9 @@ inline void init_one_table(const LEX_CSTRING *db_arg,
   st_select_lex_unit *derived;		/* SELECT_LEX_UNIT of derived table */
   With_element *with;          /* With element defining this table (if any) */
   /* Bitmap of the defining with element */
-  table_map with_internal_reference_map; 
+  table_map with_internal_reference_map;
+  TABLE_LIST * next_with_rec_ref;
+  bool is_derived_with_recursive_reference;
   bool block_handle_derived;
   ST_SCHEMA_TABLE *schema_table;        /* Information_schema table */
   st_select_lex	*schema_select_lex;
@@ -2508,6 +2510,8 @@ inline void init_one_table(const LEX_CSTRING *db_arg,
   bool is_with_table();
   bool is_recursive_with_table();
   bool is_with_table_recursive_reference();
+  void register_as_derived_with_rec_ref(With_element *rec_elem);
+  bool is_nonrecursive_derived_with_rec_ref();
   bool fill_recursive(THD *thd);
 
   inline void set_view()