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Commit 9ac235ab authored by Igor Babaev's avatar Igor Babaev
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mdev-9864: cleanup, re-factoring. 

Added comments.
Added reaction for exceeding maximum number of elements in with clause.
Added a test case to check this reaction.
Added a test case where the specification of a recursive table
uses two non-recursive with tables.
parent c8f85bf2
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Showing with 341 additions and 79 deletions
mysql-test/r/cte_nonrecursive.result
View file @ 9ac235ab
......@@ -797,6 +797,9 @@ select t1.b from t2,t1 where t1.a = t2.c;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t2 ALL NULL NULL NULL NULL 4
1 PRIMARY t1 ALL NULL NULL NULL NULL 8 Using where; Using join buffer (flat, BNL join)
# too many with elements in with clause
with s65 as (select * from t1), s64 as (select * from t1) , s63 as (select * from t1) , s62 as (select * from t1) , s61 as (select * from t1) , s60 as (select * from t1) , s59 as (select * from t1) , s58 as (select * from t1) , s57 as (select * from t1) , s56 as (select * from t1) , s55 as (select * from t1) , s54 as (select * from t1) , s53 as (select * from t1) , s52 as (select * from t1) , s51 as (select * from t1) , s50 as (select * from t1) , s49 as (select * from t1) , s48 as (select * from t1) , s47 as (select * from t1) , s46 as (select * from t1) , s45 as (select * from t1) , s44 as (select * from t1) , s43 as (select * from t1) , s42 as (select * from t1) , s41 as (select * from t1) , s40 as (select * from t1) , s39 as (select * from t1) , s38 as (select * from t1) , s37 as (select * from t1) , s36 as (select * from t1) , s35 as (select * from t1) , s34 as (select * from t1) , s33 as (select * from t1) , s32 as (select * from t1) , s31 as (select * from t1) , s30 as (select * from t1) , s29 as (select * from t1) , s28 as (select * from t1) , s27 as (select * from t1) , s26 as (select * from t1) , s25 as (select * from t1) , s24 as (select * from t1) , s23 as (select * from t1) , s22 as (select * from t1) , s21 as (select * from t1) , s20 as (select * from t1) , s19 as (select * from t1) , s18 as (select * from t1) , s17 as (select * from t1) , s16 as (select * from t1) , s15 as (select * from t1) , s14 as (select * from t1) , s13 as (select * from t1) , s12 as (select * from t1) , s11 as (select * from t1) , s10 as (select * from t1) , s9 as (select * from t1) , s8 as (select * from t1) , s7 as (select * from t1) , s6 as (select * from t1) , s5 as (select * from t1) , s4 as (select * from t1) , s3 as (select * from t1) , s2 as (select * from t1) , s1 as (select * from t1) select * from s65;
ERROR HY000: Too many WITH elements in WITH clause
drop table t1,t2;
#
# Bug mdev-9937: View used in the specification of with table
......
mysql-test/r/cte_recursive.result
View file @ 9ac235ab
......@@ -160,6 +160,8 @@ insert into folks values
(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
......@@ -182,6 +184,8 @@ id name dob father mother
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
......@@ -204,6 +208,8 @@ id name dob father mother
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
......@@ -224,29 +230,7 @@ id name dob father mother
7 Grandma Sally 1943-08-23 NULL 6
8 Grandpa Ben 1940-10-21 NULL NULL
6 Grandgrandma Martha 1923-05-17 NULL NULL
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
......@@ -282,6 +266,50 @@ 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
......@@ -300,6 +328,8 @@ id name dob father mother
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
......@@ -320,6 +350,7 @@ id name dob father mother
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
......@@ -340,6 +371,7 @@ 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
......@@ -366,6 +398,7 @@ 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
......@@ -392,6 +425,7 @@ id name dob father mother
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)
......@@ -421,6 +455,7 @@ 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)
......@@ -450,6 +485,37 @@ 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)
......@@ -478,6 +544,7 @@ 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
......@@ -507,6 +574,7 @@ 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
......@@ -537,6 +605,7 @@ 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
......@@ -607,6 +676,7 @@ NULL UNION RESULT <union3,4,5> ALL NULL NULL NULL NULL NULL NULL
2 UNCACHEABLE SUBQUERY <derived3> ALL NULL NULL NULL NULL 12 100.00 Using where
Warnings:
Note 1003 with recursive ancestor_couple_ids as (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 `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 `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 `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 `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
......@@ -640,6 +710,7 @@ NULL NULL
NULL NULL
NULL 6
NULL NULL
# join of two mutually recursive tables
with recursive
ancestor_couple_ids(h_id, w_id)
as
......@@ -669,6 +740,7 @@ 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
......@@ -705,6 +777,7 @@ id name dob father mother
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
......@@ -786,6 +859,7 @@ id select_type table type possible_keys key key_len ref rows filtered Extra
NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL NULL NULL
Warnings:
Note 1003 with recursive ancestors as (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 `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 `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
......@@ -813,6 +887,7 @@ id name dob father mother
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
......@@ -1115,6 +1190,7 @@ generation name
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
......
mysql-test/t/cte_nonrecursive.test
View file @ 9ac235ab
......@@ -469,6 +469,20 @@ explain
with t as (select a, count(*) from t1 where b >= 'c' group by a)
select t1.b from t2,t1 where t1.a = t2.c;
--echo # too many with elements in with clause
let $m= 65;
let $i= $m;
dec $i;
let $q= with s$m as (select * from t1);
while ($i)
{
let $q= $q, s$i as (select * from t1) ;
dec $i;
}
let $q= $q select * from s$m;
--ERROR ER_TOO_MANY_DEFINITIONS_IN_WITH_CLAUSE
eval $q;
drop table t1,t2;
--echo #
......
mysql-test/t/cte_recursive.test
View file @ 9ac235ab
......@@ -156,7 +156,8 @@ insert into folks values
(67, 'Cousin Eddie', '1992-02-28', 25, 27),
(27, 'Auntie Melinda', '1971-03-29', null, null);
--echo # simple recursion with one anchor and one recursive select
--echo # the anchor is the first select in the specification
with recursive
ancestors
as
......@@ -171,6 +172,8 @@ as
)
select * from ancestors;
--echo # simple recursion with one anchor and one recursive select
--echo # the anchor is the last select in the specification
with recursive
ancestors
as
......@@ -185,6 +188,8 @@ as
)
select * from ancestors;
--echo # simple recursion with one anchor and one recursive select
--echo # the anchor is the first select in the specification
with recursive
ancestors
as
......@@ -199,20 +204,8 @@ as
)
select * from ancestors;
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;
--echo # two recursive definition, one uses another
with recursive
prev_gen
as
......@@ -240,7 +233,45 @@ as
)
select ancestors.name, ancestors.dob from ancestors;
--echo # 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;
--echo # simple recursion with one anchor and one recursive select
--echo # the anchor is the first select in the specification
with recursive
descendants
as
......@@ -255,6 +286,8 @@ as
)
select * from descendants;
--echo # simple recursion with one anchor and one recursive select
--echo # the anchor is the first select in the specification
with recursive
descendants
as
......@@ -270,6 +303,7 @@ as
select * from descendants;
--echo # simple recursive table used three times in the main query
with recursive
ancestors
as
......@@ -287,6 +321,8 @@ select *
where exists (select * from ancestors a
where a.father=t1.id AND a.mother=t2.id);
--echo # simple recursive table used three times in the main query
with
ancestor_couples(husband, h_dob, wife, w_dob)
as
......@@ -310,6 +346,8 @@ select t1.name, t1.dob, t2.name, t2.dob
)
select * from ancestor_couples;
--echo # simple recursion with two selects in recursive part
with recursive
ancestors
as
......@@ -328,6 +366,8 @@ as
)
select * from ancestors;
--echo # 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)
......@@ -355,6 +395,7 @@ select h_name, h_dob, w_name, w_dob
from ancestor_couples;
--echo # 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)
......@@ -382,6 +423,35 @@ select h_name, h_dob, w_name, w_dob
from ancestor_couples;
--echo # 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;
--echo # 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)
......@@ -407,7 +477,7 @@ as
select h_name, h_dob, w_name, w_dob
from ancestor_couples;
--echo # mutual recursion with one select in the first definition
with recursive
ancestor_couple_ids(h_id, w_id)
as
......@@ -434,6 +504,8 @@ as
select *
from ancestor_couple_ids;
--echo # join of a mutually recursive table with base tables
with recursive
ancestor_couple_ids(h_id, w_id)
as
......@@ -462,6 +534,7 @@ select h.name, h.dob, w.name, w.dob
where c.h_id = h.id and c.w_id= w.id;
--echo # join of two mutually recursive tables
with recursive
ancestor_couple_ids(h_id, w_id)
as
......@@ -517,6 +590,8 @@ 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;
--echo # simple mutual recursion
with recursive
ancestor_couple_ids(h_id, w_id)
as
......@@ -543,6 +618,7 @@ select *
from ancestor_couple_ids;
--echo # join of two mutually recursive tables
with recursive
ancestor_couple_ids(h_id, w_id)
as
......@@ -570,6 +646,7 @@ select h.name, h.dob, w.name, w.dob
where c.h_id = h.id and c.w_id= w.id;
--echo # execution of prepared query using a recursive table
prepare stmt1 from "
with recursive
ancestors
......@@ -592,6 +669,7 @@ execute stmt1;
deallocate prepare stmt1;
--echo # view using a recursive table
create view v1 as
with recursive
ancestors
......@@ -636,6 +714,7 @@ select * from v2;
drop view v1,v2;
explain extended
with recursive
ancestors
......@@ -652,6 +731,7 @@ as
select * from ancestors;
--echo # recursive spec with two anchor selects and two recursive ones
with recursive
ancestor_ids (id)
as
......@@ -672,6 +752,8 @@ as
)
select * from ancestors;
--echo # recursive spec using union all
with recursive
ancestors
as
......@@ -691,8 +773,6 @@ as
select * from ancestors;
--ERROR ER_NOT_STANDARDS_COMPLIANT_RECURSIVE
with recursive
ancestor_ids (id, generation)
......@@ -937,6 +1017,8 @@ as
)
select * from ancestors;
--echo # query with recursive tables using key access
alter table folks add primary key (id);
explain
......@@ -958,6 +1040,7 @@ as
)
select * from ancestors;
with recursive
ancestors
as
......
sql/share/errmsg-utf8.txt
View file @ 9ac235ab
......@@ -7150,6 +7150,8 @@ ER_BAD_COMMAND_IN_MULTI
ukr "Команда '%s' не дозволена для COM_MULTI"
ER_WITH_COL_WRONG_LIST
eng "WITH column list and SELECT field list have different column counts"
ER_TOO_MANY_DEFINITIONS_IN_WITH_CLAUSE
eng "Too many WITH elements in WITH clause"
ER_DUP_QUERY_NAME
eng "Duplicate query name in WITH clause"
ER_RECURSIVE_WITHOUT_ANCHORS
......
sql/sql_class.h
View file @ 9ac235ab
......@@ -4681,8 +4681,11 @@ class select_union :public select_result_interceptor
class select_union_recursive :public select_union
{
public:
/* The temporary table with the new records generated by one iterative step */
TABLE *incr_table;
/* One of tables from the list rec_tables (determined dynamically) */
TABLE *first_rec_table_to_update;
/* The temporary tables used for recursive table references */
List<TABLE> rec_tables;
select_union_recursive(THD *thd_arg):
......
sql/sql_cte.cc
View file @ 9ac235ab
......@@ -6,6 +6,38 @@
#include "sql_select.h"
/**
@brief
Add a new element to this with clause
@param elem The with element to add to this with clause
@details
The method adds the with element 'elem' to the elements
in this with clause. The method reports an error if
the number of the added element exceeds the value
of the constant max_number_of_elements_in_with_clause.
@retval
true if an error is reported
false otherwise
*/
bool With_clause::add_with_element(With_element *elem)
{
if (with_list.elements == max_number_of_elements_in_with_clause)
{
my_error(ER_TOO_MANY_DEFINITIONS_IN_WITH_CLAUSE, MYF(0));
return true;
}
elem->owner= this;
elem->number= with_list.elements;
elem->spec->with_element= elem;
with_list.link_in_list(elem, &elem->next);
return false;
}
/**
@brief
Check dependencies between tables defined in a list of with clauses
......
sql/sql_cte.h
View file @ 9ac235ab
......@@ -210,6 +210,8 @@ class With_element : public Sql_alloc
friend class With_clause;
};
const uint max_number_of_elements_in_with_clause= sizeof(table_map)*8;
/**
@class With_clause
@brief Set of with_elements
......@@ -270,15 +272,7 @@ class With_clause : public Sql_alloc
with_recursive(recursive_fl)
{ }
/* Add a new element to the current with clause */
bool add_with_element(With_element *elem)
{
elem->owner= this;
elem->number= with_list.elements;
elem->spec->with_element= elem;
with_list.link_in_list(elem, &elem->next);
return false;
}
bool add_with_element(With_element *elem);
/* Add this with clause to the list of with clauses used in the statement */
void add_to_list(With_clause ** &last_next)
......
sql/sql_derived.cc
View file @ 9ac235ab
......@@ -644,16 +644,21 @@ bool mysql_derived_prepare(THD *thd, LEX *lex, TABLE_LIST *derived)
if (unit->prepared && derived->is_recursive_with_table() &&
!derived->table)
{
/*
Here 'derived' is either a non-recursive table reference to a recursive
with table or a recursive table reference to a recursvive table whose
specification has been already prepared (a secondary recursive table
reference.
*/
if (!(derived->derived_result= new (thd->mem_root) select_union(thd)))
DBUG_RETURN(TRUE); // out of memory
thd->create_tmp_table_for_derived= TRUE;
if (!derived->table)
res= derived->derived_result->create_result_table(
thd, &unit->types, FALSE,
(first_select->options |
thd->variables.option_bits |
TMP_TABLE_ALL_COLUMNS),
derived->alias, FALSE, FALSE);
res= derived->derived_result->create_result_table(
thd, &unit->types, FALSE,
(first_select->options |
thd->variables.option_bits |
TMP_TABLE_ALL_COLUMNS),
derived->alias, FALSE, FALSE);
thd->create_tmp_table_for_derived= FALSE;
if (!res && !derived->table)
......@@ -662,6 +667,7 @@ bool mysql_derived_prepare(THD *thd, LEX *lex, TABLE_LIST *derived)
derived->table= derived->derived_result->table;
if (derived->is_with_table_recursive_reference())
{
/* Here 'derived" is a secondary recursive table reference */
unit->with_element->rec_result->rec_tables.push_back(derived->table);
}
}
......@@ -685,7 +691,12 @@ bool mysql_derived_prepare(THD *thd, LEX *lex, TABLE_LIST *derived)
(!derived->with->with_anchor &&
!derived->with->is_with_prepared_anchor()))
{
// Prepare underlying views/DT first.
/*
Prepare underlying views/DT first unless 'derived' is a recursive
table reference and either the anchors from the specification of
'derived' has been already prepared or there no anchor in this
specification
*/
if ((res= sl->handle_derived(lex, DT_PREPARE)))
goto exit;
}
......@@ -922,30 +933,41 @@ bool mysql_derived_create(THD *thd, LEX *lex, TABLE_LIST *derived)
}
/**
@brief
Fill the recursive with table
@param thd The thread handle
@details
The method is called only for recursive with tables.
The method executes the recursive part of the specification
of this with table until no more rows are added to the table
or the number of the performed iteration reaches the allowed
maximum.
@retval
false on success
true on failure
*/
bool TABLE_LIST::fill_recursive(THD *thd)
{
bool rc= false;
st_select_lex_unit *unit= get_unit();
if (is_with_table_recursive_reference())
rc= with->instantiate_tmp_tables();
while (!rc && !with->all_are_stabilized())
{
if (with->level > thd->variables.max_recursive_iterations)
break;
with->prepare_for_next_iteration();
rc= unit->exec_recursive();
}
else
if (!rc)
{
rc= with->instantiate_tmp_tables();
while (!rc && !with->all_are_stabilized())
{
if (with->level > thd->variables.max_recursive_iterations)
break;
with->prepare_for_next_iteration();
rc= unit->exec_recursive();
}
if (!rc)
{
TABLE *src= with->rec_result->table;
rc =src->insert_all_rows_into(thd, table, true);
}
}
TABLE *src= with->rec_result->table;
rc =src->insert_all_rows_into(thd, table, true);
}
return rc;
}
......@@ -960,9 +982,10 @@ bool TABLE_LIST::fill_recursive(THD *thd)
@details
Execute subquery of given 'derived' table/view and fill the result
table. After result table is filled, if this is not the EXPLAIN statement,
the entire unit / node is deleted. unit is deleted if UNION is used
for derived table and node is deleted is it is a simple SELECT.
table. After result table is filled, if this is not the EXPLAIN statement
and the table is not specified with a recursion the entire unit / node
is deleted. unit is deleted if UNION is used for derived table and node
is deleted is it is a simple SELECT.
'lex' is unused and 'thd' is passed as an argument to an underlying function.
@note
......@@ -986,13 +1009,21 @@ bool mysql_derived_fill(THD *thd, LEX *lex, TABLE_LIST *derived)
DBUG_RETURN(FALSE);
/*check that table creation passed without problems. */
DBUG_ASSERT(derived->table && derived->table->is_created());
SELECT_LEX *first_select= unit->first_select();
select_union *derived_result= derived->derived_result;
SELECT_LEX *save_current_select= lex->current_select;
if (derived_is_recursive)
{
res= derived->fill_recursive(thd);
if (derived->is_with_table_recursive_reference())
{
/* Here only one iteration step is performed */
res= unit->exec_recursive();
}
else
{
/* In this case all iteration are performed */
res= derived->fill_recursive(thd);
}
}
else if (unit->is_union())
{
......@@ -1001,6 +1032,7 @@ bool mysql_derived_fill(THD *thd, LEX *lex, TABLE_LIST *derived)
}
else
{
SELECT_LEX *first_select= unit->first_select();
unit->set_limit(unit->global_parameters());
if (unit->select_limit_cnt == HA_POS_ERROR)
first_select->options&= ~OPTION_FOUND_ROWS;
......
sql/sql_union.cc
View file @ 9ac235ab
......@@ -100,6 +100,7 @@ int select_union::send_data(List<Item> &values)
return 0;
}
int select_union_recursive::send_data(List<Item> &values)
{
int rc= select_union::send_data(values);
......@@ -1166,7 +1167,29 @@ bool st_select_lex_unit::exec()
}
// One step of recursive execution
/**
@brief
Execute the union of the specification of a recursive with table
@details
The method is performed only for the units that are specifications
if recursive with table T. If the specification contains an anchor
part then the first call of this method executes only this part
while the following calls execute the recursive part. If there are
no anchors each call executes the whole unit.
Before the excution the method cleans up the temporary table
to where the new rows of the recursive table are sent.
After the execution the unit these rows are copied to the
temporary tables created for recursive references of T.
If the specification if T is restricted (standards compliant)
then these temporary tables are cleaned up before new rows
are copied into them.
@retval
false on success
true on failure
*/
bool st_select_lex_unit::exec_recursive()
{
st_select_lex *lex_select_save= thd->lex->current_select;
......
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