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mirror of https://github.com/mariadb-corporation/mariadb-columnstore-engine.git synced 2025-05-13 01:01:28 +03:00
Gagan Goel 2f1f9c0ef0 MDEV-25080 Some fixes:
1. In TupleUnion::writeNull(), add the missing switch case for
   wide decimal with 16bytes column width.
2. MCOL-5432 Disable complete/partial pushdown of UNION operation
   if the query involves an ORDER BY or a LIMIT clause, until
   MCOL-5222 is fixed. Also add MTR test cases for this.
2023-02-27 06:38:31 -05:00

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#
# MDEV-25080: Allow pushdown of queries involving UNIONs
# in outer select to foreign engines
#
# Remove the sorted_result MTR qualifier 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
SELECT * FROM t1 UNION SELECT * FROM t2;
a
abc
bcd
cde
def
efg
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
SELECT * FROM t1 UNION ALL SELECT * FROM t2;
a
abc
bcd
bcd
cde
cde
def
efg
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
SELECT * FROM t1 UNION SELECT * FROM t3;
a
abc
bcd
cde
t3_myisam1
t3_myisam2
t3_myisam3
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:
SELECT * FROM t1 UNION
SELECT * FROM t2 UNION ALL
SELECT * FROM t1;
a
abc
abc
bcd
bcd
cde
cde
def
efg
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
(SELECT * FROM t1 UNION
SELECT * FROM t2) UNION ALL
SELECT * FROM t1;
a
abc
abc
bcd
bcd
cde
cde
def
efg
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
SELECT * FROM t1 UNION
SELECT * FROM t2 UNION ALL
SELECT * FROM t3 UNION
SELECT * FROM t4;
a
abc
bcd
cde
def
efg
t3_myisam1
t3_myisam2
t3_myisam3
t4_myisam1
t4_myisam2
t4_myisam3
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
(SELECT * FROM t1 UNION
SELECT * FROM t2) UNION ALL
(SELECT * FROM t3 UNION
SELECT * FROM t4);
a
abc
bcd
cde
def
efg
t3_myisam1
t3_myisam2
t3_myisam3
t4_myisam1
t4_myisam2
t4_myisam3
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
SELECT count(*) FROM t1 UNION
SELECT count(*) FROM t2 UNION ALL
SELECT count(*)+20 FROM t2 UNION
SELECT count(*)+5 FROM t1;
count(*)
24
3
4
8
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 "SELECT * FROM t1 UNION
SELECT * FROM t2";
EXECUTE stmt;
a
abc
bcd
cde
def
efg
EXECUTE stmt;
a
abc
bcd
cde
def
efg
EXECUTE stmt;
a
abc
bcd
cde
def
efg
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 "(SELECT * FROM t1 UNION
SELECT * FROM t2) UNION ALL
(SELECT * FROM t1 UNION
SELECT * FROM t2)";
EXECUTE stmt;
a
abc
abc
bcd
bcd
cde
cde
def
def
efg
efg
EXECUTE stmt;
a
abc
abc
bcd
bcd
cde
cde
def
def
efg
efg
EXECUTE stmt;
a
abc
abc
bcd
bcd
cde
cde
def
def
efg
efg
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
# MCOL-5432 Disable UNION pushdown if an ORDER BY or a LIMIT
# clause is involved, until MCOL-5222 is fixed.
SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY a;
a
abc
bcd
bcd
cde
cde
def
efg
EXPLAIN SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY a;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 2000
2 UNION t2 ALL NULL NULL NULL NULL 2000
NULL UNION RESULT <union1,2> ALL NULL NULL NULL NULL NULL Using filesort
SELECT * FROM t1 UNION ALL SELECT * FROM t2 LIMIT 3;
a
abc
bcd
cde
EXPLAIN SELECT * FROM t1 UNION ALL SELECT * FROM t2 LIMIT 3;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 2000
2 UNION t2 ALL NULL NULL NULL NULL 2000
SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY a DESC LIMIT 5;
a
efg
def
cde
cde
bcd
EXPLAIN SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY a DESC LIMIT 5;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 2000
2 UNION t2 ALL NULL NULL NULL NULL 2000
NULL UNION RESULT <union1,2> ALL NULL NULL NULL NULL NULL Using filesort
SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY a LIMIT 3 OFFSET 2;
a
bcd
cde
cde
EXPLAIN SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY a LIMIT 3 OFFSET 2;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 2000
2 UNION t2 ALL NULL NULL NULL NULL 2000
NULL UNION RESULT <union1,2> ALL NULL NULL NULL NULL NULL Using filesort
DROP USER 'cejuser'@'localhost';
DROP TABLE t1, t2, t3, t4;
DROP DATABASE mdev25080;