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mariadb/mysql-test/r/cte_recursive.result
Igor Babaev 907b236112 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.
2018-02-22 10:26:56 -08:00

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create table t1 (a int, b varchar(32));
insert into t1 values
(4,'aaaa' ), (7,'bb'), (1,'ccc'), (4,'dd');
insert into t1 values
(3,'eee'), (7,'bb'), (1,'fff'), (4,'ggg');
with recursive
t as
(
select * from t1 where t1.b >= 'c'
union
select * from r
),
r as
(
select * from t
union
select t1.* from t1,r where r.a+1 = t1.a
)
select * from r;
ERROR HY000: Unacceptable mutual recursion with anchored table 't'
with recursive
a1(a,b) as
(select * from t1 where t1.a>3
union
select * from b1 where b1.a >3
union
select * from c1 where c1.a>3),
b1(a,b) as
(select * from a1 where a1.b > 'ccc'
union
select * from c1 where c1.b > 'ddd'),
c1(a,b) as
(select * from a1 where a1.a<6 and a1.b< 'zz'
union
select * from b1 where b1.b > 'auu')
select * from c1;
ERROR HY000: Unacceptable mutual recursion with anchored table 'a1'
drop table t1;
# WITH RECURSIVE vs just WITH
create table t1 (a int);
insert into t1 values
(0), (1), (2), (3), (4);
create table t2 (a int);
insert into t2 values
(1), (2), (3), (4), (5);
# just WITH : s refers to t defined after s
with
s(a) as (select t.a + 10 from t),
t(a) as (select t1.a from t1)
select * from s;
ERROR 42S02: Table 'test.t' doesn't exist
# WITH RECURSIVE: s refers to t defined after s
with recursive
s(a) as (select t.a + 10 from t),
t(a) as (select t1.a from t1)
select * from s;
a
10
11
12
13
14
# just WITH : defined t1 is non-recursive and uses base tables t1,t2
with
t1 as
(
select a from t2 where t2.a=3
union
select t2.a from t1,t2 where t1.a+1=t2.a
)
select * from t1;
a
3
1
2
4
5
explain
with
t1 as
(
select a from t2 where t2.a=3
union
select t2.a from t1,t2 where t1.a+1=t2.a
)
select * from t1;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 30
2 DERIVED t2 ALL NULL NULL NULL NULL 5 Using where
3 UNION t1 ALL NULL NULL NULL NULL 5
3 UNION t2 ALL NULL NULL NULL NULL 5 Using where; Using join buffer (flat, BNL join)
NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL NULL
#WITH RECURSIVE : defined t1 is recursive and uses only base table t2
with recursive
t1 as
(
select a from t2 where t2.a=3
union
select t2.a from t1,t2 where t1.a+1=t2.a
)
select * from t1;
a
3
4
5
explain
with recursive
t1 as
(
select a from t2 where t2.a=3
union
select t2.a from t1,t2 where t1.a+1=t2.a
)
select * from t1;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 5
2 DERIVED t2 ALL NULL NULL NULL NULL 5 Using where
3 RECURSIVE UNION <derived2> ALL NULL NULL NULL NULL 5
3 RECURSIVE UNION t2 ALL NULL NULL NULL NULL 5 Using where; Using join buffer (flat, BNL join)
NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL NULL
# just WITH : types of t1 columns are determined by all parts of union
create view v1 as
with
t1 as
(
select a from t2 where t2.a=3
union
select t2.a+1 from t1,t2 where t1.a=t2.a
)
select * from t1;
show columns from v1;
Field Type Null Key Default Extra
a bigint(12) YES NULL
# WITH RECURSIVE : types of t1 columns are determined by anchor parts
create view v2 as
with recursive
t1 as
(
select a from t2 where t2.a=3
union
select t2.a+1 from t1,t2 where t1.a=t2.a
)
select * from t1;
show columns from v2;
Field Type Null Key Default Extra
a int(11) YES NULL
drop view v1,v2;
drop table t1,t2;
create table folks(id int, name char(32), dob date, father int, mother int);
insert into folks values
(100, 'Me', '2000-01-01', 20, 30),
(20, 'Dad', '1970-02-02', 10, 9),
(30, 'Mom', '1975-03-03', 8, 7),
(10, 'Grandpa Bill', '1940-04-05', null, null),
(9, 'Grandma Ann', '1941-10-15', null, null),
(25, 'Uncle Jim', '1968-11-18', 8, 7),
(98, 'Sister Amy', '2001-06-20', 20, 30),
(7, 'Grandma Sally', '1943-08-23', null, 6),
(8, 'Grandpa Ben', '1940-10-21', null, null),
(6, 'Grandgrandma Martha', '1923-05-17', null, null),
(67, 'Cousin Eddie', '1992-02-28', 25, 27),
(27, 'Auntie Melinda', '1971-03-29', null, null);
# simple recursion with one anchor and one recursive select
# the anchor is the first select in the specification
with recursive
ancestors
as
(
select *
from folks
where name = 'Me' and dob = '2000-01-01'
union
select p.id, p.name, p.dob, p.father, p.mother
from folks as p, ancestors AS a
where p.id = a.father or p.id = a.mother
)
select * from ancestors;
id name dob father mother
100 Me 2000-01-01 20 30
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
# simple recursion with one anchor and one recursive select
# the anchor is the last select in the specification
with recursive
ancestors
as
(
select p.*
from folks as p, ancestors AS a
where p.id = a.father or p.id = a.mother
union
select *
from folks
where name = 'Me' and dob = '2000-01-01'
)
select * from ancestors;
id name dob father mother
100 Me 2000-01-01 20 30
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
# simple recursion with one anchor and one recursive select
# the anchor is the first select in the specification
with recursive
ancestors
as
(
select *
from folks
where name = 'Cousin Eddie'
union
select p.*
from folks as p, ancestors as a
where p.id = a.father or p.id = a.mother
)
select * from ancestors;
id name dob father mother
67 Cousin Eddie 1992-02-28 25 27
25 Uncle Jim 1968-11-18 8 7
27 Auntie Melinda 1971-03-29 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
# simple recursion with or in anchor and or in recursive part
with recursive
ancestors
as
(
select *
from folks
where name = 'Me' or name='Sister Amy'
union
select p.*
from folks as p, ancestors as a
where p.id = a.father or p.id = a.mother
)
select * from ancestors;
id name dob father mother
100 Me 2000-01-01 20 30
98 Sister Amy 2001-06-20 20 30
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
# two recursive definition, one uses another
with recursive
prev_gen
as
(
select folks.*
from folks, prev_gen
where folks.id=prev_gen.father or folks.id=prev_gen.mother
union
select *
from folks
where name='Me'
),
ancestors
as
(
select *
from folks
where name='Me'
union
select *
from ancestors
union
select *
from prev_gen
)
select ancestors.name, ancestors.dob from ancestors;
name dob
Me 2000-01-01
Dad 1970-02-02
Mom 1975-03-03
Grandpa Bill 1940-04-05
Grandma Ann 1941-10-15
Grandma Sally 1943-08-23
Grandpa Ben 1940-10-21
Grandgrandma Martha 1923-05-17
# recursive definition with two attached non-recursive
with recursive
ancestors(id,name,dob)
as
(
with
father(child_id,id,name,dob)
as
(
select folks.id, f.id, f.name, f.dob
from folks, folks f
where folks.father=f.id
),
mother(child_id,id,name,dob)
as
(
select folks.id, m.id, m.name, m.dob
from folks, folks m
where folks.mother=m.id
)
select folks.id, folks.name, folks.dob
from folks
where name='Me'
union
select f.id, f.name, f.dob
from ancestors a, father f
where f.child_id=a.id
union
select m.id, m.name, m.dob
from ancestors a, mother m
where m.child_id=a.id
)
select ancestors.name, ancestors.dob from ancestors;
name dob
Me 2000-01-01
Dad 1970-02-02
Mom 1975-03-03
Grandpa Bill 1940-04-05
Grandpa Ben 1940-10-21
Grandma Ann 1941-10-15
Grandma Sally 1943-08-23
Grandgrandma Martha 1923-05-17
# simple recursion with one anchor and one recursive select
# the anchor is the first select in the specification
with recursive
descendants
as
(
select *
from folks
where name = 'Grandpa Bill'
union
select folks.*
from folks, descendants as d
where d.id=folks.father or d.id=folks.mother
)
select * from descendants;
id name dob father mother
10 Grandpa Bill 1940-04-05 NULL NULL
20 Dad 1970-02-02 10 9
100 Me 2000-01-01 20 30
98 Sister Amy 2001-06-20 20 30
# simple recursion with one anchor and one recursive select
# the anchor is the first select in the specification
with recursive
descendants
as
(
select *
from folks
where name = 'Grandma Sally'
union
select folks.*
from folks, descendants as d
where d.id=folks.father or d.id=folks.mother
)
select * from descendants;
id name dob father mother
7 Grandma Sally 1943-08-23 NULL 6
30 Mom 1975-03-03 8 7
25 Uncle Jim 1968-11-18 8 7
100 Me 2000-01-01 20 30
98 Sister Amy 2001-06-20 20 30
67 Cousin Eddie 1992-02-28 25 27
# simple recursive table used three times in the main query
with recursive
ancestors
as
(
select *
from folks
where name = 'Me' and dob = '2000-01-01'
union
select p.*
from folks as p, ancestors AS a
where p.id = a.father OR p.id = a.mother
)
select *
from ancestors t1, ancestors t2
where exists (select * from ancestors a
where a.father=t1.id AND a.mother=t2.id);
id name dob father mother id name dob father mother
20 Dad 1970-02-02 10 9 30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL 9 Grandma Ann 1941-10-15 NULL NULL
8 Grandpa Ben 1940-10-21 NULL NULL 7 Grandma Sally 1943-08-23 NULL 6
# simple recursive table used three times in the main query
with
ancestor_couples(husband, h_dob, wife, w_dob)
as
(
with recursive
ancestors
as
(
select *
from folks
where name = 'Me'
union
select p.*
from folks as p, ancestors AS a
where p.id = a.father OR p.id = a.mother
)
select t1.name, t1.dob, t2.name, t2.dob
from ancestors t1, ancestors t2
where exists (select * from ancestors a
where a.father=t1.id AND a.mother=t2.id)
)
select * from ancestor_couples;
husband h_dob wife w_dob
Dad 1970-02-02 Mom 1975-03-03
Grandpa Bill 1940-04-05 Grandma Ann 1941-10-15
Grandpa Ben 1940-10-21 Grandma Sally 1943-08-23
# simple recursion with two selects in recursive part
with recursive
ancestors
as
(
select *
from folks
where name = 'Me'
union
select p.*
from folks as p, ancestors as fa
where p.id = fa.father
union
select p.*
from folks as p, ancestors as ma
where p.id = ma.mother
)
select * from ancestors;
id name dob father mother
100 Me 2000-01-01 20 30
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
8 Grandpa Ben 1940-10-21 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
6 Grandgrandma Martha 1923-05-17 NULL NULL
# mutual recursion with renaming
with recursive
ancestor_couples(h_id, h_name, h_dob, h_father, h_mother,
w_id, w_name, w_dob, w_father, w_mother)
as
(
select h.*, w.*
from folks h, folks w, coupled_ancestors a
where a.father = h.id AND a.mother = w.id
union
select h.*, w.*
from folks v, folks h, folks w
where v.name = 'Me' and
(v.father = h.id AND v.mother= w.id)
),
coupled_ancestors (id, name, dob, father, mother)
as
(
select h_id, h_name, h_dob, h_father, h_mother
from ancestor_couples
union
select w_id, w_name, w_dob, w_father, w_mother
from ancestor_couples
)
select h_name, h_dob, w_name, w_dob
from ancestor_couples;
h_name h_dob w_name w_dob
Dad 1970-02-02 Mom 1975-03-03
Grandpa Bill 1940-04-05 Grandma Ann 1941-10-15
Grandpa Ben 1940-10-21 Grandma Sally 1943-08-23
# mutual recursion with union all
with recursive
ancestor_couples(h_id, h_name, h_dob, h_father, h_mother,
w_id, w_name, w_dob, w_father, w_mother)
as
(
select h.*, w.*
from folks h, folks w, coupled_ancestors a
where a.father = h.id AND a.mother = w.id
union
select h.*, w.*
from folks v, folks h, folks w
where v.name = 'Me' and
(v.father = h.id AND v.mother= w.id)
),
coupled_ancestors (id, name, dob, father, mother)
as
(
select h_id, h_name, h_dob, h_father, h_mother
from ancestor_couples
union all
select w_id, w_name, w_dob, w_father, w_mother
from ancestor_couples
)
select h_name, h_dob, w_name, w_dob
from ancestor_couples;
h_name h_dob w_name w_dob
Dad 1970-02-02 Mom 1975-03-03
Grandpa Bill 1940-04-05 Grandma Ann 1941-10-15
Grandpa Ben 1940-10-21 Grandma Sally 1943-08-23
# mutual recursion with renaming
with recursive
ancestor_couples(h_id, h_name, h_dob, h_father, h_mother,
w_id, w_name, w_dob, w_father, w_mother)
as
(
select h.*, w.*
from folks h, folks w, coupled_ancestors a
where a.father = h.id AND a.mother = w.id
union
select h.*, w.*
from folks v, folks h, folks w
where v.name = 'Me' and
(v.father = h.id AND v.mother= w.id)
),
coupled_ancestors (id, name, dob, father, mother)
as
(
select h_id, h_name, h_dob, h_father, h_mother
from ancestor_couples
union
select w_id, w_name, w_dob, w_father, w_mother
from ancestor_couples
)
select h_name, h_dob, w_name, w_dob
from ancestor_couples;
h_name h_dob w_name w_dob
Dad 1970-02-02 Mom 1975-03-03
Grandpa Bill 1940-04-05 Grandma Ann 1941-10-15
Grandpa Ben 1940-10-21 Grandma Sally 1943-08-23
# mutual recursion with union all
with recursive
ancestor_couples(h_id, h_name, h_dob, h_father, h_mother,
w_id, w_name, w_dob, w_father, w_mother)
as
(
select h.*, w.*
from folks h, folks w, coupled_ancestors a
where a.father = h.id AND a.mother = w.id
),
coupled_ancestors (id, name, dob, father, mother)
as
(
select *
from folks
where name = 'Me'
union all
select h_id, h_name, h_dob, h_father, h_mother
from ancestor_couples
union all
select w_id, w_name, w_dob, w_father, w_mother
from ancestor_couples
)
select h_name, h_dob, w_name, w_dob
from ancestor_couples;
h_name h_dob w_name w_dob
Dad 1970-02-02 Mom 1975-03-03
Grandpa Bill 1940-04-05 Grandma Ann 1941-10-15
Grandpa Ben 1940-10-21 Grandma Sally 1943-08-23
# mutual recursion with one select in the first definition
with recursive
ancestor_couple_ids(h_id, w_id)
as
(
select a.father, a.mother
from coupled_ancestors a
where a.father is not null and a.mother is not null
),
coupled_ancestors (id, name, dob, father, mother)
as
(
select *
from folks
where name = 'Me'
union all
select p.*
from folks p, ancestor_couple_ids fa
where p.id = fa.h_id
union all
select p.*
from folks p, ancestor_couple_ids ma
where p.id = ma.w_id
)
select *
from ancestor_couple_ids;
h_id w_id
20 30
10 9
8 7
# join of a mutually recursive table with base tables
with recursive
ancestor_couple_ids(h_id, w_id)
as
(
select a.father, a.mother
from coupled_ancestors a
where a.father is not null and a.mother is not null
),
coupled_ancestors (id, name, dob, father, mother)
as
(
select *
from folks
where name = 'Me'
union all
select p.*
from folks p, ancestor_couple_ids fa
where p.id = fa.h_id
union all
select p.*
from folks p, ancestor_couple_ids ma
where p.id = ma.w_id
)
select h.name, h.dob, w.name, w.dob
from ancestor_couple_ids c, folks h, folks w
where c.h_id = h.id and c.w_id= w.id;
name dob name dob
Dad 1970-02-02 Mom 1975-03-03
Grandpa Bill 1940-04-05 Grandma Ann 1941-10-15
Grandpa Ben 1940-10-21 Grandma Sally 1943-08-23
# join of two mutually recursive tables
with recursive
ancestor_couple_ids(h_id, w_id)
as
(
select a.father, a.mother
from coupled_ancestors a
where a.father is not null and a.mother is not null
),
coupled_ancestors (id, name, dob, father, mother)
as
(
select *
from folks
where name = 'Me'
union all
select p.*
from folks p, ancestor_couple_ids fa
where p.id = fa.h_id
union all
select p.*
from folks p, ancestor_couple_ids ma
where p.id = ma.w_id
)
select h.name, h.dob, w.name, w.dob
from ancestor_couple_ids c, coupled_ancestors h, coupled_ancestors w
where c.h_id = h.id and c.w_id= w.id;
name dob name dob
Dad 1970-02-02 Mom 1975-03-03
Grandpa Bill 1940-04-05 Grandma Ann 1941-10-15
Grandpa Ben 1940-10-21 Grandma Sally 1943-08-23
explain extended
with recursive
ancestor_couple_ids(h_id, w_id)
as
(
select a.father, a.mother
from coupled_ancestors a
where a.father is not null and a.mother is not null
),
coupled_ancestors (id, name, dob, father, mother)
as
(
select *
from folks
where name = 'Me'
union all
select p.*
from folks p, ancestor_couple_ids fa
where p.id = fa.h_id
union all
select p.*
from folks p, ancestor_couple_ids ma
where p.id = ma.w_id
)
select h.name, h.dob, w.name, w.dob
from ancestor_couple_ids c, coupled_ancestors h, coupled_ancestors w
where c.h_id = h.id and c.w_id= w.id;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 2 100.00 Using where
1 PRIMARY <derived3> ref key0 key0 5 c.h_id 2 100.00
1 PRIMARY <derived3> ref key0 key0 5 c.w_id 2 100.00
2 DERIVED <derived3> ALL NULL NULL NULL NULL 12 100.00 Using where
3 DERIVED folks ALL NULL NULL NULL NULL 12 100.00 Using where
4 RECURSIVE UNION <derived2> ALL NULL NULL NULL NULL 2 100.00
4 RECURSIVE UNION p ALL NULL NULL NULL NULL 12 100.00 Using where; Using join buffer (flat, BNL join)
5 RECURSIVE UNION <derived2> ALL NULL NULL NULL NULL 2 100.00
5 RECURSIVE UNION p ALL NULL NULL NULL NULL 12 100.00 Using where; Using join buffer (flat, BNL join)
NULL UNION RESULT <union3,4,5> ALL NULL NULL NULL NULL NULL NULL
Warnings:
Note 1003 with recursive ancestor_couple_ids as (/* select#2 */ select `a`.`father` AS `h_id`,`a`.`mother` AS `w_id` from `coupled_ancestors` `a` where `a`.`father` is not null and `a`.`mother` is not null), coupled_ancestors as (/* select#3 */ select `test`.`folks`.`id` AS `id`,`test`.`folks`.`name` AS `name`,`test`.`folks`.`dob` AS `dob`,`test`.`folks`.`father` AS `father`,`test`.`folks`.`mother` AS `mother` from `test`.`folks` where `test`.`folks`.`name` = 'Me' union all /* select#4 */ select `test`.`p`.`id` AS `id`,`test`.`p`.`name` AS `name`,`test`.`p`.`dob` AS `dob`,`test`.`p`.`father` AS `father`,`test`.`p`.`mother` AS `mother` from `test`.`folks` `p` join `ancestor_couple_ids` `fa` where `test`.`p`.`id` = `fa`.`h_id` union all /* select#5 */ select `test`.`p`.`id` AS `id`,`test`.`p`.`name` AS `name`,`test`.`p`.`dob` AS `dob`,`test`.`p`.`father` AS `father`,`test`.`p`.`mother` AS `mother` from `test`.`folks` `p` join `ancestor_couple_ids` `ma` where `test`.`p`.`id` = `ma`.`w_id`)/* select#1 */ select `h`.`name` AS `name`,`h`.`dob` AS `dob`,`w`.`name` AS `name`,`w`.`dob` AS `dob` from `ancestor_couple_ids` `c` join `coupled_ancestors` `h` join `coupled_ancestors` `w` where `h`.`id` = `c`.`h_id` and `w`.`id` = `c`.`w_id`
# simple mutual recursion
with recursive
ancestor_couple_ids(h_id, w_id)
as
(
select a.father, a.mother
from coupled_ancestors a
),
coupled_ancestors (id, name, dob, father, mother)
as
(
select *
from folks
where name = 'Me'
union all
select p.*
from folks p, ancestor_couple_ids fa
where p.id = fa.h_id
union all
select p.*
from folks p, ancestor_couple_ids ma
where p.id = ma.w_id
)
select *
from ancestor_couple_ids;
h_id w_id
20 30
10 9
8 7
NULL NULL
NULL NULL
NULL NULL
NULL 6
NULL NULL
# join of two mutually recursive tables
with recursive
ancestor_couple_ids(h_id, w_id)
as
(
select a.father, a.mother
from coupled_ancestors a
),
coupled_ancestors (id, name, dob, father, mother)
as
(
select *
from folks
where name = 'Me'
union all
select p.*
from folks p, ancestor_couple_ids fa
where p.id = fa.h_id
union all
select p.*
from folks p, ancestor_couple_ids ma
where p.id = ma.w_id
)
select h.name, h.dob, w.name, w.dob
from ancestor_couple_ids c, coupled_ancestors h, coupled_ancestors w
where c.h_id = h.id and c.w_id= w.id;
name dob name dob
Dad 1970-02-02 Mom 1975-03-03
Grandpa Bill 1940-04-05 Grandma Ann 1941-10-15
Grandpa Ben 1940-10-21 Grandma Sally 1943-08-23
# execution of prepared query using a recursive table
prepare stmt1 from "
with recursive
ancestors
as
(
select *
from folks
where name = 'Me' and dob = '2000-01-01'
union
select p.id, p.name, p.dob, p.father, p.mother
from folks as p, ancestors AS a
where p.id = a.father or p.id = a.mother
)
select * from ancestors;
";
execute stmt1;
id name dob father mother
100 Me 2000-01-01 20 30
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
execute stmt1;
id name dob father mother
100 Me 2000-01-01 20 30
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
deallocate prepare stmt1;
# view using a recursive table
create view v1 as
with recursive
ancestors
as
(
select *
from folks
where name = 'Me' and dob = '2000-01-01'
union
select p.id, p.name, p.dob, p.father, p.mother
from folks as p, ancestors AS a
where p.id = a.father or p.id = a.mother
)
select * from ancestors;
show create view v1;
View Create View character_set_client collation_connection
v1 CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY DEFINER VIEW `v1` AS with recursive ancestors as (select `folks`.`id` AS `id`,`folks`.`name` AS `name`,`folks`.`dob` AS `dob`,`folks`.`father` AS `father`,`folks`.`mother` AS `mother` from `folks` where `folks`.`name` = 'Me' and `folks`.`dob` = '2000-01-01' union select `p`.`id` AS `id`,`p`.`name` AS `name`,`p`.`dob` AS `dob`,`p`.`father` AS `father`,`p`.`mother` AS `mother` from (`folks` `p` join `ancestors` `a`) where `p`.`id` = `a`.`father` or `p`.`id` = `a`.`mother`)select `ancestors`.`id` AS `id`,`ancestors`.`name` AS `name`,`ancestors`.`dob` AS `dob`,`ancestors`.`father` AS `father`,`ancestors`.`mother` AS `mother` from `ancestors` latin1 latin1_swedish_ci
select * from v1;
id name dob father mother
100 Me 2000-01-01 20 30
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
create view v2 as
with recursive
ancestors
as
(
select *
from folks
where name = 'Me'
union
select p.*
from folks as p, ancestors as fa
where p.id = fa.father
union
select p.*
from folks as p, ancestors as ma
where p.id = ma.mother
)
select * from ancestors;
show create view v2;
View Create View character_set_client collation_connection
v2 CREATE ALGORITHM=UNDEFINED DEFINER=`root`@`localhost` SQL SECURITY DEFINER VIEW `v2` AS with recursive ancestors as (select `folks`.`id` AS `id`,`folks`.`name` AS `name`,`folks`.`dob` AS `dob`,`folks`.`father` AS `father`,`folks`.`mother` AS `mother` from `folks` where `folks`.`name` = 'Me' union select `p`.`id` AS `id`,`p`.`name` AS `name`,`p`.`dob` AS `dob`,`p`.`father` AS `father`,`p`.`mother` AS `mother` from (`folks` `p` join `ancestors` `fa`) where `p`.`id` = `fa`.`father` union select `p`.`id` AS `id`,`p`.`name` AS `name`,`p`.`dob` AS `dob`,`p`.`father` AS `father`,`p`.`mother` AS `mother` from (`folks` `p` join `ancestors` `ma`) where `p`.`id` = `ma`.`mother`)select `ancestors`.`id` AS `id`,`ancestors`.`name` AS `name`,`ancestors`.`dob` AS `dob`,`ancestors`.`father` AS `father`,`ancestors`.`mother` AS `mother` from `ancestors` latin1 latin1_swedish_ci
select * from v2;
id name dob father mother
100 Me 2000-01-01 20 30
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
8 Grandpa Ben 1940-10-21 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
6 Grandgrandma Martha 1923-05-17 NULL NULL
drop view v1,v2;
explain extended
with recursive
ancestors
as
(
select *
from folks
where name = 'Me' and dob = '2000-01-01'
union
select p.id, p.name, p.dob, p.father, p.mother
from folks as p, ancestors AS a
where p.id = a.father or p.id = a.mother
)
select * from ancestors;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 12 100.00
2 DERIVED folks ALL NULL NULL NULL NULL 12 100.00 Using where
3 RECURSIVE UNION p ALL NULL NULL NULL NULL 12 100.00
3 RECURSIVE UNION <derived2> ALL NULL NULL NULL NULL 12 100.00 Using where; Using join buffer (flat, BNL join)
NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL NULL NULL
Warnings:
Note 1003 with recursive ancestors as (/* select#2 */ select `test`.`folks`.`id` AS `id`,`test`.`folks`.`name` AS `name`,`test`.`folks`.`dob` AS `dob`,`test`.`folks`.`father` AS `father`,`test`.`folks`.`mother` AS `mother` from `test`.`folks` where `test`.`folks`.`name` = 'Me' and `test`.`folks`.`dob` = DATE'2000-01-01' union /* select#3 */ select `p`.`id` AS `id`,`p`.`name` AS `name`,`p`.`dob` AS `dob`,`p`.`father` AS `father`,`p`.`mother` AS `mother` from `test`.`folks` `p` join `ancestors` `a` where `a`.`father` = `p`.`id` or `a`.`mother` = `p`.`id`)/* select#1 */ select `ancestors`.`id` AS `id`,`ancestors`.`name` AS `name`,`ancestors`.`dob` AS `dob`,`ancestors`.`father` AS `father`,`ancestors`.`mother` AS `mother` from `ancestors`
# recursive spec with two anchor selects and two recursive ones
with recursive
ancestor_ids (id)
as
(
select father from folks where name = 'Me'
union
select mother from folks where name = 'Me'
union
select father from folks, ancestor_ids a where folks.id = a.id
union
select mother from folks, ancestor_ids a where folks.id = a.id
),
ancestors
as
(
select p.* from folks as p, ancestor_ids as a
where p.id = a.id
)
select * from ancestors;
id name dob father mother
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
# recursive spec using union all
with recursive
ancestors
as
(
select *
from folks
where name = 'Me'
union all
select p.*
from folks as p, ancestors as fa
where p.id = fa.father
union all
select p.*
from folks as p, ancestors as ma
where p.id = ma.mother
)
select * from ancestors;
id name dob father mother
100 Me 2000-01-01 20 30
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
8 Grandpa Ben 1940-10-21 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
6 Grandgrandma Martha 1923-05-17 NULL NULL
with recursive
ancestor_ids (id, generation)
as
(
select father, 1 from folks where name = 'Me' and father is not null
union all
select mother, 1 from folks where name = 'Me' and mother is not null
union all
select father, fa.generation+1 from folks, ancestor_ids fa
where folks.id = fa.id and (father not in (select id from ancestor_ids))
union all
select mother, ma.generation+1 from folks, ancestor_ids ma
where folks.id = ma.id and (mother not in (select id from ancestor_ids))
)
select generation, name from ancestor_ids a, folks
where a.id = folks.id;
ERROR HY000: Restrictions imposed on recursive definitions are violated for table 'ancestor_ids'
set standard_compliant_cte=0;
with recursive
ancestor_ids (id, generation)
as
(
select father from folks where name = 'Me' and father is not null
union all
select mother from folks where name = 'Me' and mother is not null
union all
select father, fa.generation+1 from folks, ancestor_ids fa
where folks.id = fa.id and (father not in (select id from ancestor_ids))
union all
select mother, ma.generation+1 from folks, ancestor_ids ma
where folks.id = ma.id and (mother not in (select id from ancestor_ids))
)
select generation, name from ancestor_ids a, folks
where a.id = folks.id;
ERROR HY000: WITH column list and SELECT field list have different column counts
with recursive
ancestor_ids (id, generation)
as
(
select father, 1 from folks where name = 'Me' and father is not null
union all
select mother, 1 from folks where name = 'Me' and mother is not null
union all
select father, fa.generation+1 from folks, ancestor_ids fa
where folks.id = fa.id and father is not null and
(father not in (select id from ancestor_ids))
union all
select mother, ma.generation+1 from folks, ancestor_ids ma
where folks.id = ma.id and mother is not null and
(mother not in (select id from ancestor_ids))
)
select generation, name from ancestor_ids a, folks
where a.id = folks.id;
generation name
1 Dad
1 Mom
2 Grandpa Bill
2 Grandma Ann
2 Grandma Sally
2 Grandpa Ben
3 Grandgrandma Martha
set standard_compliant_cte=1;
with recursive
coupled_ancestor_ids (id)
as
(
select father from folks where name = 'Me' and father is not null
union
select mother from folks where name = 'Me' and mother is not null
union
select n.father
from folks, coupled_ancestor_ids fa, coupled_ancestor_ids ma, folks n
where folks.father = fa.id and folks.mother = ma.id and
(fa.id = n.id or ma.id = n.id) and
n.father is not null and n.mother is not null
union
select n.mother
from folks, coupled_ancestor_ids fa, coupled_ancestor_ids ma, folks n
where folks.father = fa.id and folks.mother = ma.id and
(fa.id = n.id or ma.id = n.id) and
n.father is not null and n.mother is not null
)
select p.* from coupled_ancestor_ids a, folks p
where a.id = p.id;
ERROR HY000: Restrictions imposed on recursive definitions are violated for table 'coupled_ancestor_ids'
set statement standard_compliant_cte=0 for
with recursive
coupled_ancestor_ids (id)
as
(
select father from folks where name = 'Me' and father is not null
union
select mother from folks where name = 'Me' and mother is not null
union
select n.father
from folks, coupled_ancestor_ids fa, coupled_ancestor_ids ma, folks n
where folks.father = fa.id and folks.mother = ma.id and
(fa.id = n.id or ma.id = n.id) and
n.father is not null and n.mother is not null
union
select n.mother
from folks, coupled_ancestor_ids fa, coupled_ancestor_ids ma, folks n
where folks.father = fa.id and folks.mother = ma.id and
(fa.id = n.id or ma.id = n.id) and
n.father is not null and n.mother is not null
)
select p.* from coupled_ancestor_ids a, folks p
where a.id = p.id;
id name dob father mother
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
with recursive
ancestor_ids (id)
as
(
select father from folks where name = 'Me'
union
select mother from folks where name = 'Me'
union
select father from folks left join ancestor_ids a on folks.id = a.id
union
select mother from folks left join ancestor_ids a on folks.id = a.id
),
ancestors
as
(
select p.* from folks as p, ancestor_ids as a
where p.id = a.id
)
select * from ancestors;
ERROR HY000: Restrictions imposed on recursive definitions are violated for table 'ancestor_ids'
set statement standard_compliant_cte=0 for
with recursive
ancestor_ids (id)
as
(
select father from folks where name = 'Me'
union
select mother from folks where name = 'Me'
union
select father from folks left join ancestor_ids a on folks.id = a.id
union
select mother from folks left join ancestor_ids a on folks.id = a.id
),
ancestors
as
(
select p.* from folks as p, ancestor_ids as a
where p.id = a.id
)
select * from ancestors;
id name dob father mother
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
25 Uncle Jim 1968-11-18 8 7
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
27 Auntie Melinda 1971-03-29 NULL NULL
with recursive
ancestor_ids (id, generation)
as
(
select father, 1 from folks where name = 'Me'
union
select mother, 1 from folks where name = 'Me'
union
select father, a.generation+1 from folks, ancestor_ids a
where folks.id = a.id
union
select mother, a.generation+1 from folks, ancestor_ids a
where folks.id = a.id
),
ancestors
as
(
select generation, name from folks as p, ancestor_ids as a
where p.id = a.id
)
select * from ancestors;
generation name
1 Dad
1 Mom
2 Grandpa Bill
2 Grandma Ann
2 Grandma Sally
2 Grandpa Ben
3 Grandgrandma Martha
with recursive
ancestor_ids (id, generation)
as
(
select father, 1 from folks where name = 'Me'
union
select mother, 1 from folks where name = 'Me'
union
select max(father), max(a.generation)+1 from folks, ancestor_ids a
where folks.id = a.id
group by a.generation
union
select max(mother), max(a.generation)+1 from folks, ancestor_ids a
where folks.id = a.id
group by a.generation
),
ancestors
as
(
select generation, name from folks as p, ancestor_ids as a
where p.id = a.id
)
select * from ancestors;
ERROR HY000: Restrictions imposed on recursive definitions are violated for table 'ancestor_ids'
set statement standard_compliant_cte=0 for
with recursive
ancestor_ids (id, generation)
as
(
select father, 1 from folks where name = 'Me'
union
select mother, 1 from folks where name = 'Me'
union
select max(father), a.generation+1 from folks, ancestor_ids a
where folks.id = a.id
group by a.generation
union
select max(mother), a.generation+1 from folks, ancestor_ids a
where folks.id = a.id
group by a.generation
),
ancestors
as
(
select generation, name from folks as p, ancestor_ids as a
where p.id = a.id
)
select * from ancestors;
generation name
1 Dad
1 Mom
2 Grandpa Bill
2 Grandma Ann
set statement max_recursive_iterations=1 for
with recursive
ancestor_ids (id, generation)
as
(
select father, 1 from folks where name = 'Me'
union
select mother, 1 from folks where name = 'Me'
union
select father, a.generation+1 from folks, ancestor_ids a
where folks.id = a.id
union
select mother, a.generation+1 from folks, ancestor_ids a
where folks.id = a.id
),
ancestors
as
(
select generation, name from folks as p, ancestor_ids as a
where p.id = a.id
)
select * from ancestors;
generation name
1 Dad
1 Mom
2 Grandpa Bill
2 Grandma Ann
2 Grandma Sally
2 Grandpa Ben
# query with recursive tables using key access
alter table folks add primary key (id);
explain
with recursive
ancestors
as
(
select *
from folks
where name = 'Me'
union
select p.*
from folks as p, ancestors as fa
where p.id = fa.father
union
select p.*
from folks as p, ancestors as ma
where p.id = ma.mother
)
select * from ancestors;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 12
2 DERIVED folks ALL NULL NULL NULL NULL 12 Using where
3 RECURSIVE UNION p ALL PRIMARY NULL NULL NULL 12
3 RECURSIVE UNION <derived2> ref key0 key0 5 test.p.id 2
4 RECURSIVE UNION p ALL PRIMARY NULL NULL NULL 12
4 RECURSIVE UNION <derived2> ref key0 key0 5 test.p.id 2
NULL UNION RESULT <union2,3,4> ALL NULL NULL NULL NULL NULL
with recursive
ancestors
as
(
select *
from folks
where name = 'Me'
union
select p.*
from folks as p, ancestors as fa
where p.id = fa.father
union
select p.*
from folks as p, ancestors as ma
where p.id = ma.mother
)
select * from ancestors;
id name dob father mother
100 Me 2000-01-01 20 30
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
8 Grandpa Ben 1940-10-21 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
6 Grandgrandma Martha 1923-05-17 NULL NULL
#
# EXPLAIN FORMAT=JSON on a query where one recursive CTE uses another:
#
explain
with recursive
prev_gen
as
(
select folks.*
from folks, prev_gen
where folks.id=prev_gen.father or folks.id=prev_gen.mother
union
select *
from folks
where name='Me'
),
ancestors
as
(
select *
from folks
where name='Me'
union
select *
from ancestors
union
select *
from prev_gen
)
select ancestors.name, ancestors.dob from ancestors;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY <derived4> ALL NULL NULL NULL NULL 24
4 DERIVED folks ALL NULL NULL NULL NULL 12 Using where
6 RECURSIVE UNION <derived3> ALL NULL NULL NULL NULL 12
3 DERIVED folks ALL NULL NULL NULL NULL 12 Using where
2 RECURSIVE UNION folks ALL PRIMARY NULL NULL NULL 12
2 RECURSIVE UNION <derived3> ALL NULL NULL NULL NULL 12 Using where; Using join buffer (flat, BNL join)
NULL UNION RESULT <union3,2> ALL NULL NULL NULL NULL NULL
5 RECURSIVE UNION <derived4> ALL NULL NULL NULL NULL 24
NULL UNION RESULT <union4,6,5> ALL NULL NULL NULL NULL NULL
explain FORMAT=JSON
with recursive
prev_gen
as
(
select folks.*
from folks, prev_gen
where folks.id=prev_gen.father or folks.id=prev_gen.mother
union
select *
from folks
where name='Me'
),
ancestors
as
(
select *
from folks
where name='Me2'
union
select *
from ancestors where id < 234
union
select *
from prev_gen where id < 345
)
select ancestors.name, ancestors.dob from ancestors;
EXPLAIN
{
"query_block": {
"select_id": 1,
"table": {
"table_name": "<derived4>",
"access_type": "ALL",
"rows": 24,
"filtered": 100,
"materialized": {
"query_block": {
"recursive_union": {
"table_name": "<union4,6,5>",
"access_type": "ALL",
"query_specifications": [
{
"query_block": {
"select_id": 4,
"table": {
"table_name": "folks",
"access_type": "ALL",
"rows": 12,
"filtered": 100,
"attached_condition": "folks.`name` = 'Me2'"
}
}
},
{
"query_block": {
"select_id": 6,
"operation": "UNION",
"table": {
"table_name": "<derived3>",
"access_type": "ALL",
"rows": 12,
"filtered": 100,
"attached_condition": "prev_gen.`id` < 345",
"materialized": {
"query_block": {
"recursive_union": {
"table_name": "<union3,2>",
"access_type": "ALL",
"query_specifications": [
{
"query_block": {
"select_id": 3,
"table": {
"table_name": "folks",
"access_type": "ALL",
"rows": 12,
"filtered": 100,
"attached_condition": "folks.`name` = 'Me'"
}
}
},
{
"query_block": {
"select_id": 2,
"operation": "UNION",
"table": {
"table_name": "folks",
"access_type": "ALL",
"possible_keys": ["PRIMARY"],
"rows": 12,
"filtered": 100
},
"block-nl-join": {
"table": {
"table_name": "<derived3>",
"access_type": "ALL",
"rows": 12,
"filtered": 100
},
"buffer_type": "flat",
"buffer_size": "256Kb",
"join_type": "BNL",
"attached_condition": "prev_gen.father = folks.`id` or prev_gen.mother = folks.`id`"
}
}
}
]
}
}
}
}
}
},
{
"query_block": {
"select_id": 5,
"operation": "UNION",
"table": {
"table_name": "<derived4>",
"access_type": "ALL",
"rows": 24,
"filtered": 100,
"attached_condition": "ancestors.`id` < 234"
}
}
}
]
}
}
}
}
}
}
#
explain format=json
with recursive
ancestor_couples(h_id, h_name, h_dob, h_father, h_mother,
w_id, w_name, w_dob, w_father, w_mother)
as
(
select h.*, w.*
from folks h, folks w, coupled_ancestors a
where a.father = h.id AND a.mother = w.id
union
select h.*, w.*
from folks v, folks h, folks w
where v.name = 'Me' and
(v.father = h.id AND v.mother= w.id)
),
coupled_ancestors (id, name, dob, father, mother)
as
(
select h_id, h_name, h_dob, h_father, h_mother
from ancestor_couples
union all
select w_id, w_name, w_dob, w_father, w_mother
from ancestor_couples
)
select h_name, h_dob, w_name, w_dob
from ancestor_couples;
EXPLAIN
{
"query_block": {
"select_id": 1,
"table": {
"table_name": "<derived3>",
"access_type": "ALL",
"rows": 12,
"filtered": 100,
"materialized": {
"query_block": {
"recursive_union": {
"table_name": "<union3,2>",
"access_type": "ALL",
"query_specifications": [
{
"query_block": {
"select_id": 3,
"table": {
"table_name": "v",
"access_type": "ALL",
"rows": 12,
"filtered": 100,
"attached_condition": "v.`name` = 'Me' and v.father is not null and v.mother is not null"
},
"table": {
"table_name": "h",
"access_type": "eq_ref",
"possible_keys": ["PRIMARY"],
"key": "PRIMARY",
"key_length": "4",
"used_key_parts": ["id"],
"ref": ["test.v.father"],
"rows": 1,
"filtered": 100
},
"table": {
"table_name": "w",
"access_type": "eq_ref",
"possible_keys": ["PRIMARY"],
"key": "PRIMARY",
"key_length": "4",
"used_key_parts": ["id"],
"ref": ["test.v.mother"],
"rows": 1,
"filtered": 100
}
}
},
{
"query_block": {
"select_id": 2,
"operation": "UNION",
"table": {
"table_name": "<derived4>",
"access_type": "ALL",
"rows": 2,
"filtered": 100,
"attached_condition": "a.father is not null and a.mother is not null"
},
"table": {
"table_name": "h",
"access_type": "eq_ref",
"possible_keys": ["PRIMARY"],
"key": "PRIMARY",
"key_length": "4",
"used_key_parts": ["id"],
"ref": ["a.father"],
"rows": 1,
"filtered": 100
},
"table": {
"table_name": "w",
"access_type": "eq_ref",
"possible_keys": ["PRIMARY"],
"key": "PRIMARY",
"key_length": "4",
"used_key_parts": ["id"],
"ref": ["a.mother"],
"rows": 1,
"filtered": 100
}
}
}
]
}
}
}
}
}
}
create table my_ancestors
with recursive
ancestor_ids (id)
as
(
select father from folks where name = 'Me'
union
select mother from folks where name = 'Me'
union
select father from folks, ancestor_ids a where folks.id = a.id
union
select mother from folks, ancestor_ids a where folks.id = a.id
)
select p.* from folks as p, ancestor_ids as a where p.id = a.id;
select * from my_ancestors;
id name dob father mother
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
delete from my_ancestors;
insert into my_ancestors
with recursive
ancestor_ids (id)
as
(
select father from folks where name = 'Me'
union
select mother from folks where name = 'Me'
union
select father from folks, ancestor_ids a where folks.id = a.id
union
select mother from folks, ancestor_ids a where folks.id = a.id
)
select p.* from folks as p, ancestor_ids as a where p.id = a.id;
select * from my_ancestors;
id name dob father mother
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
drop table my_ancestors;
#
# MDEV-10883: execution of prepared statement from SELECT
# with recursive CTE that renames columns
#
prepare stmt from"
with recursive
ancestor_ids (id)
as
(
select father from folks where name = 'Me'
union
select mother from folks where name = 'Me'
union
select father from folks, ancestor_ids a where folks.id = a.id
union
select mother from folks, ancestor_ids a where folks.id = a.id
)
select p.* from folks as p, ancestor_ids as a where p.id = a.id;
";
execute stmt;
id name dob father mother
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
deallocate prepare stmt;
#
# MDEV-10881: execution of prepared statement from
# CREATE ... SELECT, INSERT ... SELECT
#
prepare stmt from"
create table my_ancestors
with recursive
ancestor_ids (id)
as
(
select father from folks where name = 'Me'
union
select mother from folks where name = 'Me'
union
select father from folks, ancestor_ids a where folks.id = a.id
union
select mother from folks, ancestor_ids a where folks.id = a.id
)
select p.* from folks as p, ancestor_ids as a where p.id = a.id;
";
execute stmt;
deallocate prepare stmt;
select * from my_ancestors;
id name dob father mother
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
delete from my_ancestors;
prepare stmt from"
insert into my_ancestors
with recursive
ancestor_ids (id)
as
(
select father from folks where name = 'Me'
union
select mother from folks where name = 'Me'
union
select father from folks, ancestor_ids a where folks.id = a.id
union
select mother from folks, ancestor_ids a where folks.id = a.id
)
select p.* from folks as p, ancestor_ids as a where p.id = a.id;
";
execute stmt;
deallocate prepare stmt;
select * from my_ancestors;
id name dob father mother
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
drop table my_ancestors;
#
# MDEV-10933: WITH clause together with SELECT in parenthesis
# CREATE SELECT
#
create table my_ancestors
(
with recursive
ancestor_ids (id)
as
(
select father from folks where name = 'Me'
union
select mother from folks where name = 'Me'
union
select father from folks, ancestor_ids a where folks.id = a.id
union
select mother from folks, ancestor_ids a where folks.id = a.id
)
select p.* from folks as p, ancestor_ids as a where p.id = a.id
);
select * from my_ancestors;
id name dob father mother
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
drop table my_ancestors;
drop table folks;
#
# MDEV-10372: [bb-10.2-mdev9864 tree] EXPLAIN with recursive CTE enters endless recursion
#
create table t1(a int);
insert into t1 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
explain format=json
with recursive t as (select a from t1 union select a+10 from t where a < 1000)
select * from t;
EXPLAIN
{
"query_block": {
"select_id": 1,
"table": {
"table_name": "<derived2>",
"access_type": "ALL",
"rows": 10,
"filtered": 100,
"materialized": {
"query_block": {
"recursive_union": {
"table_name": "<union2,3>",
"access_type": "ALL",
"query_specifications": [
{
"query_block": {
"select_id": 2,
"table": {
"table_name": "t1",
"access_type": "ALL",
"rows": 10,
"filtered": 100
}
}
},
{
"query_block": {
"select_id": 3,
"operation": "UNION",
"table": {
"table_name": "<derived2>",
"access_type": "ALL",
"rows": 10,
"filtered": 100,
"attached_condition": "t.a < 1000"
}
}
}
]
}
}
}
}
}
}
drop table t1;
#
# MDEV-10737: recursive union with several anchors at the end
#
WITH RECURSIVE cte(n) AS
( SELECT n+1 FROM cte WHERE n < 5 UNION SELECT 1 UNION SELECT 1 )
SELECT * FROM cte;
n
1
2
3
4
5
#
# MDEV-10736: recursive definition with anchor over a table with blob
#
CREATE TABLE t1 (f VARCHAR(1024));
WITH RECURSIVE cte(f) AS
(SELECT t1.f FROM t1 UNION ALL SELECT cte.f FROM cte)
SELECT * FROM cte as t;
f
DROP TABLE t1;
#
# MDEV-10899: mergeable derived in the spec of recursive CTE
#
create table t1 (a int);
insert into t1 values
(0), (1), (2), (3), (4);
create table t2 (a int);
insert into t2 values
(1), (2), (3), (4), (5);
with recursive
t1 as
(
select x.a from (select a from t2 where t2.a=3) x
union
select t2.a from t1,t2 where t1.a+1=t2.a
)
select * from t1;
a
3
4
5
explain
with recursive
t1 as
(
select x.a from (select a from t2 where t2.a=3) x
union
select t2.a from t1,t2 where t1.a+1=t2.a
)
select * from t1;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 5
2 DERIVED t2 ALL NULL NULL NULL NULL 5 Using where
4 RECURSIVE UNION <derived2> ALL NULL NULL NULL NULL 5
4 RECURSIVE UNION t2 ALL NULL NULL NULL NULL 5 Using where; Using join buffer (flat, BNL join)
NULL UNION RESULT <union2,4> ALL NULL NULL NULL NULL NULL
drop table t1,t2;
#
# MDEV-11278: non-mergeable view in the spec of recursive CTE
#
create table t1 (a int);
insert into t1 values
(0), (1), (2), (3), (4);
create table t2 (a int);
insert into t2 values
(1), (2), (3), (4), (5);
create view v1 as
select a from t2 where a < 3
union
select a from t2 where a > 4;
with recursive
t1 as
(
select a from v1 where a=1
union
select v1.a from t1,v1 where t1.a+1=v1.a
)
select * from t1;
a
1
2
drop view v1;
drop table t1,t2;
#
# MDEV-11259: recursive CTE with concatenation operation
#
DROP TABLE IF EXISTS edges;
Warnings:
Note 1051 Unknown table 'test.edges'
CREATE TABLE edges(
a int(10) unsigned NOT NULL,
b int(10) unsigned NOT NULL,
PRIMARY KEY (a,b),
KEY b(b)
);
INSERT INTO edges
VALUES (1,3),(2,1),(2,4),(3,4),(3,5),(3,6),(4,7),(5,1),(5,6),(6,1);
DROP TABLE IF EXISTS edges2;
Warnings:
Note 1051 Unknown table 'test.edges2'
CREATE VIEW edges2 (a, b) AS
SELECT a, b FROM edges UNION ALL SELECT b, a FROM edges;
WITH RECURSIVE transitive_closure(a, b, distance, path_string) AS
( SELECT a, b, 1 AS distance,
concat(a, '.', b, '.') AS path_string
FROM edges
UNION ALL
SELECT tc.a, e.b, tc.distance + 1,
concat(tc.path_string, e.b, '.') AS path_string
FROM edges AS e
JOIN transitive_closure AS tc
ON e.a = tc.b
WHERE tc.path_string NOT LIKE concat('%', e.b, '.%')
)
SELECT * FROM transitive_closure
ORDER BY a, b, distance;
a b distance path_string
1 3 1 1.3.
1 4 2 1.3.4.
1 5 2 1.3.5.
1 6 2 1.3.6.
1 6 3 1.3.5.6.
1 7 3 1.3.4.7.
2 1 1 2.1.
2 3 2 2.1.3.
2 4 1 2.4.
2 4 3 2.1.3.4.
2 5 3 2.1.3.5.
2 6 3 2.1.3.6.
2 6 4 2.1.3.5.6.
2 7 2 2.4.7.
2 7 4 2.1.3.4.7.
3 1 2 3.5.1.
3 1 2 3.6.1.
3 1 3 3.5.6.1.
3 4 1 3.4.
3 5 1 3.5.
3 6 1 3.6.
3 6 2 3.5.6.
3 7 2 3.4.7.
4 7 1 4.7.
5 1 1 5.1.
5 1 2 5.6.1.
5 3 2 5.1.3.
5 3 3 5.6.1.3.
5 4 3 5.1.3.4.
5 4 4 5.6.1.3.4.
5 6 1 5.6.
5 6 3 5.1.3.6.
5 7 4 5.1.3.4.7.
5 7 5 5.6.1.3.4.7.
6 1 1 6.1.
6 3 2 6.1.3.
6 4 3 6.1.3.4.
6 5 3 6.1.3.5.
6 7 4 6.1.3.4.7.
WITH RECURSIVE transitive_closure(a, b, distance, path_string) AS
( SELECT a, b, 1 AS distance,
concat(a, '.', b, '.') AS path_string
FROM edges
WHERE a = 1 -- source
UNION ALL
SELECT tc.a, e.b, tc.distance + 1,
concat(tc.path_string, e.b, '.') AS path_string
FROM edges AS e
JOIN transitive_closure AS tc ON e.a = tc.b
WHERE tc.path_string NOT LIKE concat('%', e.b, '.%')
)
SELECT * FROM transitive_closure
WHERE b = 6 -- destination
ORDER BY a, b, distance;
a b distance path_string
1 6 2 1.3.6.
1 6 3 1.3.5.6.
WITH RECURSIVE transitive_closure(a, b, distance, path_string) AS
( SELECT a, b, 1 AS distance,
concat(a, '.', b, '.') AS path_string
FROM edges2
UNION ALL
SELECT tc.a, e.b, tc.distance + 1,
concat(tc.path_string, e.b, '.') AS path_string
FROM edges2 AS e
JOIN transitive_closure AS tc ON e.a = tc.b
WHERE tc.path_string NOT LIKE concat('%', e.b, '.%')
)
SELECT * FROM transitive_closure
ORDER BY a, b, distance;
a b distance path_string
1 2 1 1.2.
1 2 3 1.3.4.2.
1 2 4 1.5.3.4.2.
1 2 4 1.6.3.4.2.
1 2 5 1.5.6.3.4.2.
1 2 5 1.6.5.3.4.2.
1 3 1 1.3.
1 3 2 1.5.3.
1 3 2 1.6.3.
1 3 3 1.2.4.3.
1 3 3 1.5.6.3.
1 3 3 1.6.5.3.
1 4 2 1.2.4.
1 4 2 1.3.4.
1 4 3 1.5.3.4.
1 4 3 1.6.3.4.
1 4 4 1.5.6.3.4.
1 4 4 1.6.5.3.4.
1 5 1 1.5.
1 5 2 1.3.5.
1 5 2 1.6.5.
1 5 3 1.3.6.5.
1 5 3 1.6.3.5.
1 5 4 1.2.4.3.5.
1 5 5 1.2.4.3.6.5.
1 6 1 1.6.
1 6 2 1.3.6.
1 6 2 1.5.6.
1 6 3 1.3.5.6.
1 6 3 1.5.3.6.
1 6 4 1.2.4.3.6.
1 6 5 1.2.4.3.5.6.
1 7 3 1.2.4.7.
1 7 3 1.3.4.7.
1 7 4 1.5.3.4.7.
1 7 4 1.6.3.4.7.
1 7 5 1.5.6.3.4.7.
1 7 5 1.6.5.3.4.7.
2 1 1 2.1.
2 1 3 2.4.3.1.
2 1 4 2.4.3.5.1.
2 1 4 2.4.3.6.1.
2 1 5 2.4.3.5.6.1.
2 1 5 2.4.3.6.5.1.
2 3 2 2.1.3.
2 3 2 2.4.3.
2 3 3 2.1.5.3.
2 3 3 2.1.6.3.
2 3 4 2.1.5.6.3.
2 3 4 2.1.6.5.3.
2 4 1 2.4.
2 4 3 2.1.3.4.
2 4 4 2.1.5.3.4.
2 4 4 2.1.6.3.4.
2 4 5 2.1.5.6.3.4.
2 4 5 2.1.6.5.3.4.
2 5 2 2.1.5.
2 5 3 2.1.3.5.
2 5 3 2.1.6.5.
2 5 3 2.4.3.5.
2 5 4 2.1.3.6.5.
2 5 4 2.1.6.3.5.
2 5 4 2.4.3.1.5.
2 5 4 2.4.3.6.5.
2 5 5 2.4.3.1.6.5.
2 5 5 2.4.3.6.1.5.
2 6 2 2.1.6.
2 6 3 2.1.3.6.
2 6 3 2.1.5.6.
2 6 3 2.4.3.6.
2 6 4 2.1.3.5.6.
2 6 4 2.1.5.3.6.
2 6 4 2.4.3.1.6.
2 6 4 2.4.3.5.6.
2 6 5 2.4.3.1.5.6.
2 6 5 2.4.3.5.1.6.
2 7 2 2.4.7.
2 7 4 2.1.3.4.7.
2 7 5 2.1.5.3.4.7.
2 7 5 2.1.6.3.4.7.
2 7 6 2.1.5.6.3.4.7.
2 7 6 2.1.6.5.3.4.7.
3 1 1 3.1.
3 1 2 3.5.1.
3 1 2 3.6.1.
3 1 3 3.4.2.1.
3 1 3 3.5.6.1.
3 1 3 3.6.5.1.
3 2 2 3.1.2.
3 2 2 3.4.2.
3 2 3 3.5.1.2.
3 2 3 3.6.1.2.
3 2 4 3.5.6.1.2.
3 2 4 3.6.5.1.2.
3 4 1 3.4.
3 4 3 3.1.2.4.
3 4 4 3.5.1.2.4.
3 4 4 3.6.1.2.4.
3 4 5 3.5.6.1.2.4.
3 4 5 3.6.5.1.2.4.
3 5 1 3.5.
3 5 2 3.1.5.
3 5 2 3.6.5.
3 5 3 3.1.6.5.
3 5 3 3.6.1.5.
3 5 4 3.4.2.1.5.
3 5 5 3.4.2.1.6.5.
3 6 1 3.6.
3 6 2 3.1.6.
3 6 2 3.5.6.
3 6 3 3.1.5.6.
3 6 3 3.5.1.6.
3 6 4 3.4.2.1.6.
3 6 5 3.4.2.1.5.6.
3 7 2 3.4.7.
3 7 4 3.1.2.4.7.
3 7 5 3.5.1.2.4.7.
3 7 5 3.6.1.2.4.7.
3 7 6 3.5.6.1.2.4.7.
3 7 6 3.6.5.1.2.4.7.
4 1 2 4.2.1.
4 1 2 4.3.1.
4 1 3 4.3.5.1.
4 1 3 4.3.6.1.
4 1 4 4.3.5.6.1.
4 1 4 4.3.6.5.1.
4 2 1 4.2.
4 2 3 4.3.1.2.
4 2 4 4.3.5.1.2.
4 2 4 4.3.6.1.2.
4 2 5 4.3.5.6.1.2.
4 2 5 4.3.6.5.1.2.
4 3 1 4.3.
4 3 3 4.2.1.3.
4 3 4 4.2.1.5.3.
4 3 4 4.2.1.6.3.
4 3 5 4.2.1.5.6.3.
4 3 5 4.2.1.6.5.3.
4 5 2 4.3.5.
4 5 3 4.2.1.5.
4 5 3 4.3.1.5.
4 5 3 4.3.6.5.
4 5 4 4.2.1.3.5.
4 5 4 4.2.1.6.5.
4 5 4 4.3.1.6.5.
4 5 4 4.3.6.1.5.
4 5 5 4.2.1.3.6.5.
4 5 5 4.2.1.6.3.5.
4 6 2 4.3.6.
4 6 3 4.2.1.6.
4 6 3 4.3.1.6.
4 6 3 4.3.5.6.
4 6 4 4.2.1.3.6.
4 6 4 4.2.1.5.6.
4 6 4 4.3.1.5.6.
4 6 4 4.3.5.1.6.
4 6 5 4.2.1.3.5.6.
4 6 5 4.2.1.5.3.6.
4 7 1 4.7.
5 1 1 5.1.
5 1 2 5.3.1.
5 1 2 5.6.1.
5 1 3 5.3.6.1.
5 1 3 5.6.3.1.
5 1 4 5.3.4.2.1.
5 1 5 5.6.3.4.2.1.
5 2 2 5.1.2.
5 2 3 5.3.1.2.
5 2 3 5.3.4.2.
5 2 3 5.6.1.2.
5 2 4 5.1.3.4.2.
5 2 4 5.3.6.1.2.
5 2 4 5.6.3.1.2.
5 2 4 5.6.3.4.2.
5 2 5 5.1.6.3.4.2.
5 2 5 5.6.1.3.4.2.
5 3 1 5.3.
5 3 2 5.1.3.
5 3 2 5.6.3.
5 3 3 5.1.6.3.
5 3 3 5.6.1.3.
5 3 4 5.1.2.4.3.
5 3 5 5.6.1.2.4.3.
5 4 2 5.3.4.
5 4 3 5.1.2.4.
5 4 3 5.1.3.4.
5 4 3 5.6.3.4.
5 4 4 5.1.6.3.4.
5 4 4 5.3.1.2.4.
5 4 4 5.6.1.2.4.
5 4 4 5.6.1.3.4.
5 4 5 5.3.6.1.2.4.
5 4 5 5.6.3.1.2.4.
5 6 1 5.6.
5 6 2 5.1.6.
5 6 2 5.3.6.
5 6 3 5.1.3.6.
5 6 3 5.3.1.6.
5 6 5 5.1.2.4.3.6.
5 6 5 5.3.4.2.1.6.
5 7 3 5.3.4.7.
5 7 4 5.1.2.4.7.
5 7 4 5.1.3.4.7.
5 7 4 5.6.3.4.7.
5 7 5 5.1.6.3.4.7.
5 7 5 5.3.1.2.4.7.
5 7 5 5.6.1.2.4.7.
5 7 5 5.6.1.3.4.7.
5 7 6 5.3.6.1.2.4.7.
5 7 6 5.6.3.1.2.4.7.
6 1 1 6.1.
6 1 2 6.3.1.
6 1 2 6.5.1.
6 1 3 6.3.5.1.
6 1 3 6.5.3.1.
6 1 4 6.3.4.2.1.
6 1 5 6.5.3.4.2.1.
6 2 2 6.1.2.
6 2 3 6.3.1.2.
6 2 3 6.3.4.2.
6 2 3 6.5.1.2.
6 2 4 6.1.3.4.2.
6 2 4 6.3.5.1.2.
6 2 4 6.5.3.1.2.
6 2 4 6.5.3.4.2.
6 2 5 6.1.5.3.4.2.
6 2 5 6.5.1.3.4.2.
6 3 1 6.3.
6 3 2 6.1.3.
6 3 2 6.5.3.
6 3 3 6.1.5.3.
6 3 3 6.5.1.3.
6 3 4 6.1.2.4.3.
6 3 5 6.5.1.2.4.3.
6 4 2 6.3.4.
6 4 3 6.1.2.4.
6 4 3 6.1.3.4.
6 4 3 6.5.3.4.
6 4 4 6.1.5.3.4.
6 4 4 6.3.1.2.4.
6 4 4 6.5.1.2.4.
6 4 4 6.5.1.3.4.
6 4 5 6.3.5.1.2.4.
6 4 5 6.5.3.1.2.4.
6 5 1 6.5.
6 5 2 6.1.5.
6 5 2 6.3.5.
6 5 3 6.1.3.5.
6 5 3 6.3.1.5.
6 5 5 6.1.2.4.3.5.
6 5 5 6.3.4.2.1.5.
6 7 3 6.3.4.7.
6 7 4 6.1.2.4.7.
6 7 4 6.1.3.4.7.
6 7 4 6.5.3.4.7.
6 7 5 6.1.5.3.4.7.
6 7 5 6.3.1.2.4.7.
6 7 5 6.5.1.2.4.7.
6 7 5 6.5.1.3.4.7.
6 7 6 6.3.5.1.2.4.7.
6 7 6 6.5.3.1.2.4.7.
7 1 3 7.4.2.1.
7 1 3 7.4.3.1.
7 1 4 7.4.3.5.1.
7 1 4 7.4.3.6.1.
7 1 5 7.4.3.5.6.1.
7 1 5 7.4.3.6.5.1.
7 2 2 7.4.2.
7 2 4 7.4.3.1.2.
7 2 5 7.4.3.5.1.2.
7 2 5 7.4.3.6.1.2.
7 2 6 7.4.3.5.6.1.2.
7 2 6 7.4.3.6.5.1.2.
7 3 2 7.4.3.
7 3 4 7.4.2.1.3.
7 3 5 7.4.2.1.5.3.
7 3 5 7.4.2.1.6.3.
7 3 6 7.4.2.1.5.6.3.
7 3 6 7.4.2.1.6.5.3.
7 4 1 7.4.
7 5 3 7.4.3.5.
7 5 4 7.4.2.1.5.
7 5 4 7.4.3.1.5.
7 5 4 7.4.3.6.5.
7 5 5 7.4.2.1.3.5.
7 5 5 7.4.2.1.6.5.
7 5 5 7.4.3.1.6.5.
7 5 5 7.4.3.6.1.5.
7 5 6 7.4.2.1.3.6.5.
7 5 6 7.4.2.1.6.3.5.
7 6 3 7.4.3.6.
7 6 4 7.4.2.1.6.
7 6 4 7.4.3.1.6.
7 6 4 7.4.3.5.6.
7 6 5 7.4.2.1.3.6.
7 6 5 7.4.2.1.5.6.
7 6 5 7.4.3.1.5.6.
7 6 5 7.4.3.5.1.6.
7 6 6 7.4.2.1.3.5.6.
7 6 6 7.4.2.1.5.3.6.
WITH RECURSIVE transitive_closure(a, b, distance, path_string)
AS
( SELECT a, b, 1 AS distance,
concat(a, '.', b, '.') AS path_string
FROM edges2
UNION ALL
SELECT tc.a, e.b, tc.distance + 1,
concat(tc.path_string, e.b, '.') AS path_string
FROM edges2 AS e
JOIN transitive_closure AS tc ON e.a = tc.b
WHERE tc.path_string NOT LIKE concat('%', e.b, '.%')
)
SELECT a, b, min(distance) AS dist FROM transitive_closure
GROUP BY a, b
ORDER BY a, dist, b;
a b dist
1 2 1
1 3 1
1 4 2
1 5 1
1 6 1
1 7 3
2 1 1
2 3 2
2 4 1
2 5 2
2 6 2
2 7 2
3 1 1
3 2 2
3 4 1
3 5 1
3 6 1
3 7 2
4 1 2
4 2 1
4 3 1
4 5 2
4 6 2
4 7 1
5 1 1
5 2 2
5 3 1
5 4 2
5 6 1
5 7 3
6 1 1
6 2 2
6 3 1
6 4 2
6 5 1
6 7 3
7 1 3
7 2 2
7 3 2
7 4 1
7 5 3
7 6 3
DROP VIEW edges2;
DROP TABLE edges;
#
# MDEV-11674: recursive CTE table that cannot be stored
# in a heap table
#
create table t1 (id int, test_data varchar(36));
insert into t1(id, test_data)
select id, test_data
from (
with recursive data_generator(id, test_data) as (
select 1 as id, uuid() as test_data
union all
select id + 1, uuid() from data_generator where id < 150000
)
select * from data_generator
) as a;
drop table t1;
#
# MDEV-10773: ANALYZE for query with recursive CTE
#
analyze format=json
with recursive src(counter) as
(select 1
union
select counter+1 from src where counter<10
) select * from src;
ANALYZE
{
"query_block": {
"select_id": 1,
"r_loops": 1,
"r_total_time_ms": "REPLACED",
"table": {
"table_name": "<derived2>",
"access_type": "ALL",
"r_loops": 1,
"rows": 2,
"r_rows": 10,
"r_total_time_ms": "REPLACED",
"filtered": 100,
"r_filtered": 100,
"materialized": {
"query_block": {
"recursive_union": {
"table_name": "<union2,3>",
"access_type": "ALL",
"r_loops": 0,
"r_rows": null,
"query_specifications": [
{
"query_block": {
"select_id": 2,
"table": {
"message": "No tables used"
}
}
},
{
"query_block": {
"select_id": 3,
"operation": "UNION",
"r_loops": 10,
"r_total_time_ms": "REPLACED",
"table": {
"table_name": "<derived2>",
"access_type": "ALL",
"r_loops": 10,
"rows": 2,
"r_rows": 1,
"r_total_time_ms": "REPLACED",
"filtered": 100,
"r_filtered": 90,
"attached_condition": "src.counter < 10"
}
}
}
]
}
}
}
}
}
}
#
# mdev-12360: recursive reference in left operand of LEFT JOIN
#
create table folks(id int, name char(32), dob date, father int, mother int);
insert into folks values
(100, 'Me', '2000-01-01', 20, 30),
(20, 'Dad', '1970-02-02', 10, 9),
(30, 'Mom', '1975-03-03', 8, 7),
(10, 'Grandpa Bill', '1940-04-05', null, null),
(9, 'Grandma Ann', '1941-10-15', null, null),
(25, 'Uncle Jim', '1968-11-18', 8, 7),
(98, 'Sister Amy', '2001-06-20', 20, 30),
(7, 'Grandma Sally', '1943-08-23', null, 6),
(8, 'Grandpa Ben', '1940-10-21', null, null),
(6, 'Grandgrandma Martha', '1923-05-17', null, null),
(67, 'Cousin Eddie', '1992-02-28', 25, 27),
(27, 'Auntie Melinda', '1971-03-29', null, null);
with recursive
ancestor_ids (id)
as
(
select father from folks where name = 'Me'
union
select mother from folks where name = 'Me'
union
select father from ancestor_ids as a left join folks on folks.id = a.id
union
select mother from ancestor_ids as a left join folks on folks.id = a.id
),
ancestors
as
(
select p.* from folks as p, ancestor_ids as a
where p.id = a.id
)
select * from ancestors;
id name dob father mother
20 Dad 1970-02-02 10 9
30 Mom 1975-03-03 8 7
10 Grandpa Bill 1940-04-05 NULL NULL
9 Grandma Ann 1941-10-15 NULL NULL
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
drop table folks;
#
# mdev-12368: crash with mutually recursive CTE
# that arenot Standard compliant
#
create table value_nodes (v char(4));
create table module_nodes(m char(4));
create table module_arguments(m char(4), v char(4));
create table module_results(m char(4), v char(4));
with recursive
reached_values as
(
select v from value_nodes where v in ('v3','v7','v9')
union
select module_results.v from module_results, applied_modules
where module_results.m = applied_modules.m
),
applied_modules as
(
select module_nodes.m
from
module_nodes
left join
(
module_arguments
left join
reached_values
on module_arguments.v = reached_values.v
)
on reached_values.v is null and
module_nodes.m = module_arguments.m
where module_arguments.m is null
)
select * from reached_values;
ERROR HY000: Restrictions imposed on recursive definitions are violated for table 'applied_modules'
drop table value_nodes, module_nodes, module_arguments, module_results;
#
# mdev-12375: query using one of two mutually recursive CTEs
# whose non-recursive part returns an empty set
#
create table value_nodes (v char(4));
insert into value_nodes values
('v1'), ('v2'), ('v3'), ('v4'), ('v5'), ('v6'), ('v7'), ('v8'), ('v9'),
('v10'), ('v11'), ('v12'), ('v13'), ('v14'), ('v15'), ('v16');
create table module_nodes(m char(4));
insert into module_nodes values
('m1'), ('m2'), ('m3'), ('m4'), ('m5'), ('m6'), ('m7');
create table module_arguments(m char(4), v char(4));
insert into module_arguments values
('m1','v3'), ('m1','v9'),
('m2','v4'), ('m2','v3'), ('m2','v7'),
('m3','v6'),
('m4','v4'), ('m4','v1'),
('m5','v10'), ('m5','v8'), ('m5','v3'),
('m6','v8'), ('m6','v1'),
('m7','v11'), ('m7','v12');
create table module_results(m char(4), v char(4));
insert into module_results values
('m1','v4'),
('m2','v1'), ('m2','v6'),
('m3','v10'),
('m4','v8'),
('m5','v11'), ('m5','v9'),
('m6','v12'), ('m6','v4'),
('m7','v2');
set statement max_recursive_iterations=2, standard_compliant_cte=0 for
with recursive
reached_values as
(
select v from value_nodes where v in ('v3','v7','v9')
union
select module_results.v from module_results, applied_modules
where module_results.m = applied_modules.m
),
applied_modules as
(
select * from module_nodes where 1=0
union
select module_nodes.m
from
module_nodes
left join
(
module_arguments
left join
reached_values
on module_arguments.v = reached_values.v
)
on reached_values.v is null and
module_nodes.m = module_arguments.m
where module_arguments.m is null
)
select * from applied_modules;
m
m1
m2
drop table value_nodes, module_nodes, module_arguments, module_results;
#
# mdev-12519: recursive references in subqueries
#
create table t1 (lp char(4) not null, rp char(4) not null);
insert into t1 values
('p1','p2'), ('p2','p3'), ('p3','p4'), ('p4','p5'),
('p2','p7'), ('p7','p8'), ('p8','p3'), ('p8','p4');
set standard_compliant_cte=0;
with recursive
reachables(p) as
(
select lp from t1 where lp = 'p1'
union
select t1.rp from reachables, t1
where t1.lp = reachables.p
)
select * from reachables;
p
p1
p2
p3
p7
p4
p8
p5
with recursive
reachables(p) as
(
select lp from t1 where lp = 'p1'
union
select t1.rp from reachables, t1
where 'p3' not in (select * from reachables) and
t1.lp = reachables.p
)
select * from reachables;
p
p1
p2
p3
p7
with recursive
reachables(p) as
(
select lp from t1 where lp = 'p1'
union
select t1.rp from reachables, t1
where 'p3' not in (select p from reachables where p <= 'p5'
union
select p from reachables where p > 'p5') and
t1.lp = reachables.p
)
select * from reachables;
p
p1
p2
p3
p7
prepare stmt from "
with recursive
reachables(p) as
(
select lp from t1 where lp = 'p1'
union
select t1.rp from reachables, t1
where 'p3' not in (select p from reachables where p <= 'p5'
union
select p from reachables where p > 'p5') and
t1.lp = reachables.p
)
select * from reachables;
";
execute stmt;
p
p1
p2
p3
p7
execute stmt;
p
p1
p2
p3
p7
deallocate prepare stmt;
drop table t1;
create table objects(v char(4) not null);
insert into objects values
('v1'), ('v2'), ('v3'), ('v4'), ('v5'),
('v6'), ('v7'), ('v8'), ('v9'), ('v10');
create table modules(m char(4) not null);
insert into modules values
('m1'), ('m2'), ('m3'), ('m4');
create table module_arguments(m char(4) not null, v char(4) not null);
insert into module_arguments values
('m1','v3'), ('m1','v9'),
('m2','v4'), ('m2','v7'),
('m3','v6'), ('m4','v2');
create table module_results(m char(4) not null, v char(4) not null);
insert into module_results values
('m1','v4'),
('m2','v1'), ('m2','v6'),
('m3','v10'), ('m4','v7');
set standard_compliant_cte=0;
with recursive
reached_objects as
(
select v, 'init' as m from objects where v in ('v3','v7','v9')
union
select module_results.v, module_results.m from module_results, applied_modules
where module_results.m = applied_modules.m
),
applied_modules as
(
select * from modules where 1=0
union
select modules.m
from
modules
where
not exists (select * from module_arguments
where module_arguments.m = modules.m and
module_arguments.v not in
(select v from reached_objects))
)
select * from reached_objects;
v m
v3 init
v7 init
v9 init
v4 m1
v1 m2
v6 m2
v10 m3
with recursive
reached_objects as
(
select v, 'init' as m from objects where v in ('v3','v7','v9')
union
select module_results.v, module_results.m from module_results, applied_modules
where module_results.m = applied_modules.m
),
applied_modules as
(
select * from modules where 1=0
union
select modules.m
from
modules
where
'v6' not in (select v from reached_objects) and
not exists (select * from module_arguments
where module_arguments.m = modules.m and
module_arguments.v not in
(select v from reached_objects))
)
select * from reached_objects;
v m
v3 init
v7 init
v9 init
v4 m1
v1 m2
v6 m2
prepare stmt from "
with recursive
reached_objects as
(
select v, 'init' as m from objects where v in ('v3','v7','v9')
union
select module_results.v, module_results.m from module_results, applied_modules
where module_results.m = applied_modules.m
),
applied_modules as
(
select * from modules where 1=0
union
select modules.m
from
modules
where
'v6' not in (select v from reached_objects) and
not exists (select * from module_arguments
where module_arguments.m = modules.m and
module_arguments.v not in
(select v from reached_objects))
)
select * from reached_objects;
";
execute stmt;
v m
v3 init
v7 init
v9 init
v4 m1
v1 m2
v6 m2
execute stmt;
v m
v3 init
v7 init
v9 init
v4 m1
v1 m2
v6 m2
deallocate prepare stmt;
drop table objects, modules, module_arguments, module_results;
set standard_compliant_cte=default;
select @@standard_compliant_cte;
@@standard_compliant_cte
1
#
# mdev-12554: impossible where in recursive select
#
CREATE TABLE t1 (i int);
INSERT INTO t1 VALUES (1),(2);
WITH RECURSIVE
cte(f) AS ( SELECT i FROM t1 UNION SELECT f FROM t1, cte WHERE 1=0 )
SELECT * FROM cte;
f
1
2
DROP TABLE t1;
#
# mdev-12556: recursive execution uses Aria temporary tables
#
CREATE TABLE t (c1 varchar(255), c2 tinytext);
INSERT INTO t VALUES ('a','a'),('b','b'),('c','c'),('d','d');
ANALYZE WITH RECURSIVE cte(f) AS (
SELECT c1 FROM t
UNION
SELECT c1 FROM t, cte
) SELECT COUNT(*) FROM cte;
id select_type table type possible_keys key key_len ref rows r_rows filtered r_filtered Extra
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 4 4.00 100.00 100.00
2 DERIVED t ALL NULL NULL NULL NULL 4 4.00 100.00 100.00
3 RECURSIVE UNION t ALL NULL NULL NULL NULL 4 4.00 100.00 100.00
3 RECURSIVE UNION <derived2> ALL NULL NULL NULL NULL 4 4.00 100.00 100.00 Using join buffer (flat, BNL join)
NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL NULL 0.00 NULL NULL
WITH RECURSIVE cte(f) AS (
SELECT c1 FROM t
UNION
SELECT c1 FROM t, cte
) SELECT COUNT(*) FROM cte;
COUNT(*)
4
ANALYZE WITH RECURSIVE cte(f) AS (
SELECT c2 FROM t
UNION
SELECT c2 FROM t, cte
) SELECT COUNT(*) FROM cte;
id select_type table type possible_keys key key_len ref rows r_rows filtered r_filtered Extra
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 4 4.00 100.00 100.00
2 DERIVED t ALL NULL NULL NULL NULL 4 4.00 100.00 100.00
3 RECURSIVE UNION t ALL NULL NULL NULL NULL 4 4.00 100.00 100.00
3 RECURSIVE UNION <derived2> ALL NULL NULL NULL NULL 4 4.00 100.00 100.00 Using join buffer (flat, BNL join)
NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL NULL 0.00 NULL NULL
WITH RECURSIVE cte(f) AS (
SELECT c2 FROM t
UNION
SELECT c2 FROM t, cte
) SELECT COUNT(*) FROM cte;
COUNT(*)
4
DROP TABLE t;
#
# mdev-12563: no recursive references on the top level of the CTE spec
#
CREATE TABLE t (i int);
INSERT INTO t VALUES (3), (1),(2);
SET standard_compliant_cte=0;
WITH RECURSIVE cte(f) AS (
SELECT i FROM t
UNION
SELECT i FROM t WHERE i NOT IN ( SELECT * FROM cte )
) SELECT * FROM cte;
f
3
1
2
WITH RECURSIVE cte(f) AS (
SELECT i FROM t
UNION
SELECT i FROM t WHERE i NOT IN ( SELECT * FROM cte WHERE i < 2 )
UNION
SELECT i FROM t WHERE i NOT IN ( SELECT * FROM cte WHERE i > 2 )
) SELECT * FROM cte;
f
3
1
2
WITH RECURSIVE cte(f) AS (
SELECT i FROM t
UNION
SELECT i FROM t
WHERE i NOT IN ( SELECT * FROM cte WHERE i < 2
UNION
SELECT * FROM cte WHERE i > 2)
) SELECT * FROM cte;
f
3
1
2
WITH RECURSIVE cte(f) AS (
SELECT i FROM t
UNION
SELECT i FROM t
WHERE i NOT IN ( SELECT * FROM t
WHERE i IN ( SELECT * FROM cte ) GROUP BY i )
) SELECT * FROM cte;
f
3
1
2
WITH RECURSIVE cte(f) AS (
SELECT i FROM t
UNION
SELECT i FROM t WHERE i NOT IN ( SELECT * FROM cte )
UNION
SELECT * FROM cte WHERE f > 2
) SELECT * FROM cte;
f
3
1
2
set standard_compliant_cte=default;
DROP TABLE t;
#
# mdev-14184: recursive CTE embedded into CTE with multiple references
#
WITH
cte1 AS (
SELECT n FROM (
WITH RECURSIVE rec_cte(n) AS (
SELECT 1 as n1
UNION ALL
SELECT n+1 as n2 FROM rec_cte WHERE n < 3
) SELECT n FROM rec_cte
) AS X
),
cte2 as (
SELECT 2 FROM cte1
)
SELECT *
FROM cte1;
n
1
2
3
#
# mdev-14629: a user-defined variable is defined by the recursive CTE
#
set @var=
(
with recursive cte_tab(a) as (
select 1
union
select a+1 from cte_tab
where a<3)
select count(*) from cte_tab
);
select @var;
@var
3
create table t1(a int, b int);
insert into t1 values (3,8),(1,5),(5,7),(7,4),(4,3);
set @var=
(
with recursive summ(a,s) as (
select 1, 0 union
select t1.b, t1.b+summ.s from summ, t1
where summ.a=t1.a)
select s from summ
order by a desc
limit 1
);
select @var;
@var
27
set @var=
(
with recursive
cte_1 as (
select 1
union
select * from cte_2),
cte_2 as (
select * from cte_1
union
select a from t1, cte_2
where t1.a=cte_2.a)
select * from cte_2
limit 1
);
ERROR HY000: Unacceptable mutual recursion with anchored table 'cte_1'
drop table t1;
#
# mdev-14777: crash caused by the same as in mdev-14755
#
CREATE TABLE t1 (i1 int NOT NULL, i2 int);
CREATE TABLE t2 (d1 int NOT NULL PRIMARY KEY);
CREATE TABLE t3 (i int );
insert into t1 select seq,seq from seq_1_to_100000;
insert into t2 select seq from seq_1000_to_100000;
insert into t3 select seq from seq_1_to_1000;
SELECT *
FROM
(
SELECT *
FROM
(
WITH RECURSIVE rt AS
(
SELECT i2 P, i1 C FROM t1 WHERE i1 IN (SELECT d1 FROM t2)
UNION
SELECT t1.i2 P, rt.C C FROM t1, rt
)
SELECT C,P
FROM ( SELECT P,C FROM rt WHERE NOT EXISTS (SELECT 1 FROM t1) ) Y
) X
WHERE 1 = 1
) K, t3;
C P i
drop table t1,t2,t3;
#
# mdev-14879: subquery with recursive reference in WHERE of CTE
#
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', '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'),
('Moscow', 'Tokyo', 'Aeroflot', 'SU 264'),
('New York', 'Paris', 'Air France', 'AF 23'),
('Frankfurt', 'Moscow', 'Lufthansa', 'LH 1444'),
('Tokyo', 'Seattle', 'ANA', 'NH 178'),
('Los Angeles', 'Tokyo', 'ANA', 'NH 175'),
('Moscow', 'Los Angeles', 'Aeroflot', 'SU 106'),
('Montreal', 'Paris', 'Air Canada', 'AC 870'),
('Cairo', 'Paris', 'Air France', 'AF 503'),
('New York', 'Seattle', 'American', 'AA 45'),
('Paris', 'Chicago', 'Air France', 'AF 6734');
with recursive destinations (city) as
( select a.arrival from flights a where a.departure='Cairo'
union
select b.arrival from destinations r, flights b where r.city=b.departure)
select * from destinations;
city
Paris
Chicago
New York
Montreal
Seattle
Frankfurt
Los Angeles
Moscow
Tokyo
set standard_compliant_cte=0;
with recursive destinations (city, legs) as
(
select a.arrival, 1 from flights a where a.departure='Cairo'
union
select b.arrival, r.legs + 1 from destinations r, flights b
where r.city=b.departure and b.arrival not in (select city from destinations)
)
select * from destinations;
city legs
Paris 1
Chicago 2
New York 3
Montreal 3
Seattle 4
Frankfurt 5
Los Angeles 5
Moscow 6
Tokyo 6
explain extended with recursive destinations (city, legs) as
(
select a.arrival, 1 from flights a where a.departure='Cairo'
union
select b.arrival, r.legs + 1 from destinations r, flights b
where r.city=b.departure and b.arrival not in (select city from destinations)
)
select * from destinations;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 16 100.00
2 DERIVED a ALL NULL NULL NULL NULL 16 100.00 Using where
3 RECURSIVE UNION b ALL NULL NULL NULL NULL 16 100.00 Using where
3 RECURSIVE UNION <derived2> ref key0 key0 35 test.b.departure 2 100.00
4 DEPENDENT SUBQUERY <derived2> ALL NULL NULL NULL NULL 16 100.00 Using where
NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL NULL NULL
Warnings:
Note 1003 with recursive destinations as (/* select#2 */ select `test`.`a`.`arrival` AS `city`,1 AS `legs` from `test`.`flights` `a` where `test`.`a`.`departure` = 'Cairo' union /* select#3 */ select `test`.`b`.`arrival` AS `arrival`,`r`.`legs` + 1 AS `r.legs + 1` from `destinations` `r` join `test`.`flights` `b` where `r`.`city` = `test`.`b`.`departure` and !<in_optimizer>(`test`.`b`.`arrival`,<exists>(/* select#4 */ select `destinations`.`city` from `destinations` where trigcond(`test`.`b`.`arrival` = `destinations`.`city` or `destinations`.`city` is null) having trigcond(`destinations`.`city` is null))))/* select#1 */ select `destinations`.`city` AS `city`,`destinations`.`legs` AS `legs` from `destinations`
set standard_compliant_cte=default;
drop table flights;
#
# MDEV-15162: Setting user variable in recursive CTE
#
SET @c=1;
WITH RECURSIVE cte AS
(SELECT 5
UNION
SELECT @c:=@c+1 FROM cte WHERE @c<3)
SELECT * FROM cte;
5
5
2
3
#
# MDEV-14217 [db crash] Recursive CTE when SELECT includes new field
#
CREATE TEMPORARY TABLE a_tbl (
a VARCHAR(33) PRIMARY KEY,
b VARCHAR(33)
);
INSERT INTO a_tbl VALUES ('block0', 'block0'), ('block1', NULL);
WITH RECURSIVE Q0 AS (
SELECT T0.a, T0.b, 5
FROM a_tbl T0
WHERE b IS NULL
UNION ALL
SELECT T1.a, T1.b
FROM Q0
JOIN a_tbl T1
ON T1.a=Q0.a
) SELECT distinct(Q0.a), Q0.b
FROM Q0;
ERROR 21000: The used SELECT statements have a different number of columns
DROP TABLE a_tbl;
WITH RECURSIVE x AS (SELECT 1,2 UNION ALL SELECT 1 FROM x) SELECT * FROM x;
ERROR 21000: The used SELECT statements have a different number of columns
#
# MDEV-15162: Setting user variable in recursive CTE
#
SET @c=1;
WITH RECURSIVE cte AS
(SELECT 5
UNION
SELECT @c:=@c+1 FROM cte WHERE @c<3)
SELECT * FROM cte;
5
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;
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