database/mariadb-columnstore-engine
1
0
Fork 0
mirror of https://github.com/mariadb-corporation/mariadb-columnstore-engine.git synced 2025-07-30 19:23:07 +03:00
Code Activity

MDEV-25080 Implement ColumnStore-side changes for pushdown of SELECT_LEX_UNITs.

Browse Source
This commit is contained in:
Gagan Goel
2022-08-31 16:46:15 -04:00
parent 8671f55784
commit 45a779f743
11 changed files with 551 additions and 126 deletions
Download Patch File Download Diff File Expand all files Collapse all files

114
mysql-test/columnstore/basic/r/mdev-25080.result Normal file
View File

@ -0,0 +1,114 @@
#
# MDEV-25080: Allow pushdown of queries involving UNIONs
# in outer select to foreign engines
#
# Uncomment the actual SELECTs and add ORDER BY clause
# after MCOL-5222 is fixed
#
CREATE USER IF NOT EXISTS'cejuser'@'localhost' IDENTIFIED BY 'Vagrant1|0000001';
GRANT ALL PRIVILEGES ON *.* TO 'cejuser'@'localhost';
FLUSH PRIVILEGES;
DROP DATABASE IF EXISTS mdev25080;
CREATE DATABASE mdev25080;
USE mdev25080;
CREATE TABLE t1 (a varchar(30)) ENGINE=ColumnStore;
CREATE TABLE t2 (a varchar(30)) ENGINE=ColumnStore;
CREATE TABLE t3 (a varchar(30)) ENGINE=MyISAM;
CREATE TABLE t4 (a varchar(30)) ENGINE=MyISAM;
INSERT INTO t1 VALUES ('abc'), ('bcd'), ('cde');
INSERT INTO t2 VALUES ('bcd'), ('cde'), ('def'), ('efg');
INSERT INTO t3 VALUES ('t3_myisam1'), ('t3_myisam2'), ('t3_myisam3');
INSERT INTO t4 VALUES ('t4_myisam1'), ('t4_myisam2'), ('t4_myisam3');
# Pushdown of the whole UNION
EXPLAIN SELECT * FROM t1 UNION SELECT * FROM t2;
id select_type table type possible_keys key key_len ref rows Extra
NULL PUSHED UNION NULL NULL NULL NULL NULL NULL NULL NULL
EXPLAIN SELECT * FROM t1 UNION ALL SELECT * FROM t2;
id select_type table type possible_keys key key_len ref rows Extra
NULL PUSHED UNION NULL NULL NULL NULL NULL NULL NULL NULL
# UNION with a foreign engine
EXPLAIN SELECT * FROM t1 UNION SELECT * FROM t3;
id select_type table type possible_keys key key_len ref rows Extra
NULL PUSHED UNION NULL NULL NULL NULL NULL NULL NULL NULL
# More than two SELECTs in a UNIT:
EXPLAIN SELECT * FROM t1 UNION
SELECT * FROM t2 UNION ALL
SELECT * FROM t1;
id select_type table type possible_keys key key_len ref rows Extra
NULL PUSHED UNION NULL NULL NULL NULL NULL NULL NULL NULL
EXPLAIN (SELECT * FROM t1 UNION
SELECT * FROM t2) UNION ALL
SELECT * FROM t1;
id select_type table type possible_keys key key_len ref rows Extra
NULL PUSHED UNION NULL NULL NULL NULL NULL NULL NULL NULL
EXPLAIN SELECT * FROM t1 UNION
SELECT * FROM t2 UNION ALL
SELECT * FROM t3 UNION
SELECT * FROM t4;
id select_type table type possible_keys key key_len ref rows Extra
NULL PUSHED UNION NULL NULL NULL NULL NULL NULL NULL NULL
EXPLAIN (SELECT * FROM t1 UNION
SELECT * FROM t2) UNION ALL
(SELECT * FROM t3 UNION
SELECT * FROM t4);
id select_type table type possible_keys key key_len ref rows Extra
NULL PUSHED UNION NULL NULL NULL NULL NULL NULL NULL NULL
EXPLAIN
SELECT count(*) FROM t1 UNION
SELECT count(*) FROM t2 UNION ALL
SELECT count(*)+20 FROM t2 UNION
SELECT count(*)+5 FROM t1;
id select_type table type possible_keys key key_len ref rows Extra
NULL PUSHED UNION NULL NULL NULL NULL NULL NULL NULL NULL
# UNION inside a derived table: the whole derived table must be pushed
SELECT a FROM
(SELECT a FROM t1 UNION ALL SELECT a FROM t2) q ORDER BY a;
a
abc
bcd
bcd
cde
cde
def
efg
EXPLAIN
SELECT a FROM
(SELECT a FROM t1 UNION ALL SELECT a FROM t2) q ORDER BY a;
id select_type table type possible_keys key key_len ref rows Extra
1 PUSHED SELECT NULL NULL NULL NULL NULL NULL NULL NULL
SELECT a FROM
(SELECT a FROM t1 UNION ALL SELECT a FROM t3) q ORDER BY a;
a
abc
bcd
cde
t3_myisam1
t3_myisam2
t3_myisam3
EXPLAIN
SELECT a FROM
(SELECT a FROM t1 UNION ALL SELECT a FROM t3) q ORDER BY a;
id select_type table type possible_keys key key_len ref rows Extra
1 PUSHED SELECT NULL NULL NULL NULL NULL NULL NULL NULL
# Prepared statements
PREPARE stmt FROM "EXPLAIN SELECT * FROM t1 UNION
SELECT * FROM t2";
EXECUTE stmt;
id select_type table type possible_keys key key_len ref rows Extra
NULL PUSHED UNION NULL NULL NULL NULL NULL NULL NULL NULL
EXECUTE stmt;
id select_type table type possible_keys key key_len ref rows Extra
NULL PUSHED UNION NULL NULL NULL NULL NULL NULL NULL NULL
PREPARE stmt FROM "EXPLAIN (SELECT * FROM t1 UNION
SELECT * FROM t2) UNION ALL
(SELECT * FROM t1 UNION
SELECT * FROM t2)";
EXECUTE stmt;
id select_type table type possible_keys key key_len ref rows Extra
NULL PUSHED UNION NULL NULL NULL NULL NULL NULL NULL NULL
EXECUTE stmt;
id select_type table type possible_keys key key_len ref rows Extra
NULL PUSHED UNION NULL NULL NULL NULL NULL NULL NULL NULL
DROP USER 'cejuser'@'localhost';
DROP TABLE t1, t2, t3, t4;
DROP DATABASE mdev25080;