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|
connect master,127.0.0.1,root,,test,$MASTER_MYPORT,;
connect slave,127.0.0.1,root,,test,$SLAVE_MYPORT,;
connection master;
CREATE DATABASE federated;
connection slave;
CREATE DATABASE federated;
connection default;
set global federated_pushdown=1;
connection slave;
DROP TABLE IF EXISTS federated.t1;
Warnings:
Note 1051 Unknown table 'federated.t1'
CREATE TABLE federated.t1 (
id int(20) NOT NULL,
name varchar(16) NOT NULL default ''
)
DEFAULT CHARSET=latin1;
INSERT INTO federated.t1 VALUES
(3,'xxx'), (7,'yyy'), (4,'xxx'), (1,'zzz'), (5,'yyy');
DROP TABLE IF EXISTS federated.t2;
Warnings:
Note 1051 Unknown table 'federated.t2'
CREATE TABLE federated.t2 (
name varchar(16) NOT NULL default ''
)
DEFAULT CHARSET=latin1;
INSERT INTO federated.t2 VALUES
('yyy'), ('www'), ('yyy'), ('xxx'), ('www'), ('yyy'), ('www');
connection master;
DROP TABLE IF EXISTS federated.t1;
Warnings:
Note 1051 Unknown table 'federated.t1'
CREATE TABLE federated.t1 (
id int(20) NOT NULL,
name varchar(16) NOT NULL default ''
)
ENGINE="FEDERATED" DEFAULT CHARSET=latin1
CONNECTION='mysql://root@127.0.0.1:SLAVE_PORT/federated/t1';
DROP TABLE IF EXISTS federated.t2;
Warnings:
Note 1051 Unknown table 'federated.t2'
CREATE TABLE federated.t2 (
name varchar(16) NOT NULL default ''
)
ENGINE="FEDERATED" DEFAULT CHARSET=latin1
CONNECTION='mysql://root@127.0.0.1:SLAVE_PORT/federated/t2';
SELECT * FROM federated.t1;
id name
3 xxx
7 yyy
4 xxx
1 zzz
5 yyy
SELECT id FROM federated.t1 WHERE id < 5;
id
3
4
1
SELECT count(*), name FROM federated.t1 WHERE id < 5 GROUP BY name;
count(*) name
2 xxx
1 zzz
SELECT * FROM federated.t1, federated.t2
WHERE federated.t1.name = federated.t2.name;
id name name
7 yyy yyy
5 yyy yyy
7 yyy yyy
5 yyy yyy
3 xxx xxx
4 xxx xxx
7 yyy yyy
5 yyy yyy
SELECT * FROM federated.t1 LEFT JOIN federated.t2
ON federated.t1.name = federated.t2.name
WHERE federated.t1.id > 1;
id name name
7 yyy yyy
5 yyy yyy
7 yyy yyy
5 yyy yyy
3 xxx xxx
4 xxx xxx
7 yyy yyy
5 yyy yyy
SELECT * FROM federated.t1
WHERE id IN (SELECT count(*) FROM federated.t2 GROUP BY name);
id name
3 xxx
1 zzz
EXPLAIN
SELECT id FROM federated.t1 WHERE id < 5;
id select_type table type possible_keys key key_len ref rows Extra
1 PUSHED SELECT NULL NULL NULL NULL NULL NULL NULL NULL
EXPLAIN EXTENDED
SELECT id FROM federated.t1 WHERE id < 5;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PUSHED SELECT NULL NULL NULL NULL NULL NULL NULL NULL NULL
Warnings:
Note 1003 select `federated`.`t1`.`id` AS `id` from `federated`.`t1` where `federated`.`t1`.`id` < 5
EXPLAIN FORMAT=JSON
SELECT id FROM federated.t1 WHERE id < 5;
EXPLAIN
{
"query_block": {
"select_id": 1,
"table": {
"message": "Pushed select"
}
}
}
ANALYZE
SELECT id FROM federated.t1 WHERE id < 5;
id select_type table type possible_keys key key_len ref rows r_rows filtered r_filtered Extra
1 PUSHED SELECT NULL NULL NULL NULL NULL NULL NULL NULL NULL NULL NULL
ANALYZE FORMAT=JSON
SELECT id FROM federated.t1 WHERE id < 5;
ANALYZE
{
"query_block": {
"select_id": 1,
"table": {
"message": "Pushed select"
}
}
}
CREATE TABLE federated.t3 (
name varchar(16) NOT NULL default ''
)
DEFAULT CHARSET=latin1;
INSERT INTO federated.t3 VALUES
('yyy'), ('www'), ('yyy'), ('xxx'), ('www'), ('yyy'), ('www');
SELECT *
FROM federated.t3, (SELECT * FROM federated.t1 WHERE id > 3) t
WHERE federated.t3.name=t.name;
name id name
yyy 5 yyy
yyy 7 yyy
yyy 5 yyy
yyy 7 yyy
xxx 4 xxx
yyy 5 yyy
yyy 7 yyy
EXPLAIN
SELECT *
FROM federated.t3, (SELECT * FROM federated.t1 WHERE id > 3) t
WHERE federated.t3.name=t.name;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t3 ALL NULL NULL NULL NULL 7
1 PRIMARY <derived2> ref key0 key0 18 federated.t3.name 2
2 PUSHED DERIVED NULL NULL NULL NULL NULL NULL NULL NULL
EXPLAIN FORMAT=JSON
SELECT *
FROM federated.t3, (SELECT * FROM federated.t1 WHERE id > 3) t
WHERE federated.t3.name=t.name;
EXPLAIN
{
"query_block": {
"select_id": 1,
"nested_loop": [
{
"table": {
"table_name": "t3",
"access_type": "ALL",
"rows": 7,
"filtered": 100
}
},
{
"table": {
"table_name": "<derived2>",
"access_type": "ref",
"possible_keys": ["key0"],
"key": "key0",
"key_length": "18",
"used_key_parts": ["name"],
"ref": ["federated.t3.name"],
"rows": 2,
"filtered": 100,
"materialized": {
"query_block": {
"select_id": 2,
"table": {
"message": "Pushed derived"
}
}
}
}
}
]
}
}
ANALYZE
SELECT *
FROM federated.t3, (SELECT * FROM federated.t1 WHERE id > 3) t
WHERE federated.t3.name=t.name;
id select_type table type possible_keys key key_len ref rows r_rows filtered r_filtered Extra
1 PRIMARY t3 ALL NULL NULL NULL NULL 7 7.00 100.00 100.00
1 PRIMARY <derived2> ref key0 key0 18 federated.t3.name 2 0.00 100.00 100.00
2 PUSHED DERIVED NULL NULL NULL NULL NULL NULL NULL NULL NULL NULL NULL
SELECT *
FROM federated.t3, (SELECT t1.name FROM federated.t1
WHERE id IN (SELECT count(*)
FROM federated.t2 GROUP BY name)) t
WHERE federated.t3.name=t.name;
name name
xxx xxx
EXPLAIN
SELECT *
FROM federated.t3, (SELECT t1.name FROM federated.t1
WHERE id IN (SELECT count(*)
FROM federated.t2 GROUP BY name)) t
WHERE federated.t3.name=t.name;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t3 ALL NULL NULL NULL NULL 7
1 PRIMARY <derived2> ref key0 key0 18 federated.t3.name 2
2 PUSHED DERIVED NULL NULL NULL NULL NULL NULL NULL NULL
ANALYZE FORMAT=JSON
SELECT *
FROM federated.t3, (SELECT t1.name FROM federated.t1
WHERE id IN (SELECT count(*)
FROM federated.t2 GROUP BY name)) t
WHERE federated.t3.name=t.name;
ANALYZE
{
"query_block": {
"select_id": 1,
"r_loops": 1,
"r_total_time_ms": "REPLACED",
"nested_loop": [
{
"table": {
"table_name": "t3",
"access_type": "ALL",
"r_loops": 1,
"rows": 7,
"r_rows": 7,
"r_table_time_ms": "REPLACED",
"r_other_time_ms": "REPLACED",
"filtered": 100,
"r_filtered": 100
}
},
{
"table": {
"table_name": "<derived2>",
"access_type": "ref",
"possible_keys": ["key0"],
"key": "key0",
"key_length": "18",
"used_key_parts": ["name"],
"ref": ["federated.t3.name"],
"r_loops": 7,
"rows": 2,
"r_rows": 0,
"r_table_time_ms": "REPLACED",
"r_other_time_ms": "REPLACED",
"filtered": 100,
"r_filtered": 100,
"materialized": {
"query_block": {
"select_id": 2,
"table": {
"message": "Pushed derived"
}
}
}
}
}
]
}
}
SELECT t.id, federated.t3.name
FROM federated.t3,
( SELECT * FROM federated.t1 WHERE id < 3
UNION
SELECT * FROM federated.t1 WHERE id >= 5) t
WHERE federated.t3.name=t.name;
id name
5 yyy
7 yyy
5 yyy
7 yyy
5 yyy
7 yyy
EXPLAIN
SELECT t.id, federated.t3.name
FROM federated.t3,
( SELECT * FROM federated.t1 WHERE id < 3
UNION
SELECT * FROM federated.t1 WHERE id >= 5) t
WHERE federated.t3.name=t.name;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t3 ALL NULL NULL NULL NULL 7
1 PRIMARY <derived2> ref key0 key0 18 federated.t3.name 2
2 PUSHED DERIVED NULL NULL NULL NULL NULL NULL NULL NULL
#
# MDEV-21887: federatedx crashes on SELECT ... INTO query in select_handler code
#
CREATE TABLE federated.t4 (
id int(20) NOT NULL,
name varchar(16) NOT NULL default ''
) engine=myisam;
insert into federated.t4 select * from federated.t1;
select * from federated.t4;
id name
1 zzz
3 xxx
4 xxx
5 yyy
7 yyy
select name into @var from federated.t1 where id=3 limit 1 ;
select @var;
@var
xxx
select name into outfile 'tmp.txt' from federated.t1;
#
# MDEV-22993: Crash on EXPLAIN with PUSHED DOWN SELECT and subquery
#
explain
select * from federated.t1
where name in (select name from federated.t2);
id select_type table type possible_keys key key_len ref rows Extra
1 PUSHED SELECT NULL NULL NULL NULL NULL NULL NULL NULL
explain format=json
select * from federated.t1
where name in (select name from federated.t2);
EXPLAIN
{
"query_block": {
"select_id": 1,
"table": {
"message": "Pushed select"
}
}
}
#
# MDEV-22993, testcase #2: EXPLAIN output doesn't make sense when
# derived table pushdown is used.
#
create table t5 (a int) engine=myisam;
insert into t5 values (1),(2);
# Must not show lines with id=3
explain
select * from t5,
(select id from federated.t1
where name in (select name from federated.t2) or name like 'foo%') as TQ;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t5 ALL NULL NULL NULL NULL 2
1 PRIMARY <derived2> ALL NULL NULL NULL NULL 5 Using join buffer (flat, BNL join)
2 PUSHED DERIVED NULL NULL NULL NULL NULL NULL NULL NULL
# Must not show elements with select_id=3
explain format=json
select * from t5,
(select id from federated.t1
where name in (select name from federated.t2) or name like 'foo%') as TQ;
EXPLAIN
{
"query_block": {
"select_id": 1,
"nested_loop": [
{
"table": {
"table_name": "t5",
"access_type": "ALL",
"rows": 2,
"filtered": 100
}
},
{
"block-nl-join": {
"table": {
"table_name": "<derived2>",
"access_type": "ALL",
"rows": 5,
"filtered": 100
},
"buffer_type": "flat",
"buffer_size": "65",
"join_type": "BNL",
"materialized": {
"query_block": {
"select_id": 2,
"table": {
"message": "Pushed derived"
}
}
}
}
}
]
}
}
drop table t5;
DROP TABLE federated.t1, federated.t2, federated.t3, federated.t4;
connection slave;
DROP TABLE federated.t1, federated.t2;
connection default;
#
# MDEV-23778: Derived handler used for big derived tables
#
connection slave;
CREATE TABLE federated.t1 (
a varchar(100) NOT NULL default '123'
)
DEFAULT CHARSET=latin1;
CREATE TABLE federated.t2 LIKE federated.t1;
BEGIN NOT ATOMIC
DECLARE i INT DEFAULT 0;
START TRANSACTION;
WHILE i < 70000 DO
INSERT INTO federated.t1 VALUES (i);
SET i = i + 1;
END WHILE;
COMMIT;
END
$$
connection master;
CREATE TABLE federated.t1 (
a varchar(100) NOT NULL default '123'
)
ENGINE="FEDERATED" DEFAULT CHARSET=latin1
CONNECTION='mysql://root@127.0.0.1:SLAVE_PORT/federated/t1';
CREATE TABLE federated.t2 (
a varchar(100) NOT NULL default '123'
)
ENGINE="FEDERATED" DEFAULT CHARSET=latin1
CONNECTION='mysql://root@127.0.0.1:SLAVE_PORT/federated/t2';
SELECT COUNT(DISTINCT a) FROM federated.t1;
COUNT(DISTINCT a)
70000
INSERT INTO federated.t2
SELECT * FROM (SELECT * FROM federated.t1 LIMIT 100) dt;
SELECT COUNT(DISTINCT a) FROM federated.t2;
COUNT(DISTINCT a)
100
TRUNCATE TABLE federated.t2;
INSERT INTO federated.t2
SELECT * FROM (SELECT * FROM federated.t1 LIMIT 70000) dt;
SELECT COUNT(DISTINCT a) FROM federated.t2;
COUNT(DISTINCT a)
70000
set global federated_pushdown=0;
connection master;
DROP TABLE IF EXISTS federated.t1;
DROP DATABASE IF EXISTS federated;
connection slave;
DROP TABLE IF EXISTS federated.t1;
DROP DATABASE IF EXISTS federated;
|
