--echo #
--echo # MDEV-25080: Allow pushdown of queries involving UNIONs
--echo # in outer select to foreign engines

--source ../include/have_columnstore.inc
--source ../include/disable_11.8.inc

if (!$MASTER_MYPORT)
{
  # Running with --extern
  let $MASTER_MYPORT=`SELECT @@port`;
}

#
# Enable cross engine join
# Configure user and password in Columnstore.xml file
#
--exec $MCS_MCSSETCONFIG CrossEngineSupport User 'cejuser'
--exec $MCS_MCSSETCONFIG CrossEngineSupport Password 'Vagrant1|0000001'
--exec $MCS_MCSSETCONFIG CrossEngineSupport Port $MASTER_MYPORT

#
# Create corresponding in the server
#
--disable_warnings
CREATE USER IF NOT EXISTS'cejuser'@'localhost' IDENTIFIED BY 'Vagrant1|0000001';
--enable_warnings
GRANT ALL PRIVILEGES ON *.* TO 'cejuser'@'localhost';
FLUSH PRIVILEGES;

--disable_warnings
DROP DATABASE IF EXISTS mdev25080;
--enable_warnings

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');

--echo # Pushdown of the whole UNION
SELECT * FROM t1 UNION SELECT * FROM t2 ORDER BY 1;
EXPLAIN SELECT * FROM t1 UNION SELECT * FROM t2 ORDER BY 1;

SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY 1;
EXPLAIN SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY 1;

--echo # UNION with a foreign engine
SELECT * FROM t1 UNION SELECT * FROM t3 ORDER BY 1;
EXPLAIN SELECT * FROM t1 UNION SELECT * FROM t3 ORDER BY 1;

--echo # More than two SELECTs in a UNIT:
SELECT * FROM t1 UNION
  SELECT * FROM t2 UNION ALL
  SELECT * FROM t1
ORDER BY 1;

EXPLAIN SELECT * FROM t1 UNION
  SELECT * FROM t2 UNION ALL
  SELECT * FROM t1
ORDER BY 1;

(SELECT * FROM t1 UNION
  SELECT * FROM t2) UNION ALL
  SELECT * FROM t1
ORDER BY 1;

EXPLAIN (SELECT * FROM t1 UNION
  SELECT * FROM t2) UNION ALL
  SELECT * FROM t1
ORDER BY 1;

SELECT * FROM t1 UNION
  SELECT * FROM t2 UNION ALL
  SELECT * FROM t3 UNION
  SELECT * FROM t4
ORDER BY 1;

EXPLAIN SELECT * FROM t1 UNION
  SELECT * FROM t2 UNION ALL
  SELECT * FROM t3 UNION
  SELECT * FROM t4
ORDER BY 1;

(SELECT * FROM t1 UNION
  SELECT * FROM t2) UNION ALL
  (SELECT * FROM t3 UNION
  SELECT * FROM t4)
ORDER BY 1;

EXPLAIN (SELECT * FROM t1 UNION
  SELECT * FROM t2) UNION ALL
  (SELECT * FROM t3 UNION
  SELECT * FROM t4)
ORDER BY 1;

SELECT count(*) FROM t1 UNION
  SELECT count(*) FROM t2 UNION ALL
  SELECT count(*)+20 FROM t2 UNION
  SELECT count(*)+5 FROM t1
ORDER BY 1;

EXPLAIN
  SELECT count(*) FROM t1 UNION
  SELECT count(*) FROM t2 UNION ALL
  SELECT count(*)+20 FROM t2 UNION
  SELECT count(*)+5 FROM t1
ORDER BY 1;

--echo # 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;

EXPLAIN
  SELECT a FROM
    (SELECT a FROM t1 UNION ALL SELECT a FROM t2) q ORDER BY a;

SELECT a FROM
  (SELECT a FROM t1 UNION ALL SELECT a FROM t3) q ORDER BY a;

EXPLAIN
  SELECT a FROM
    (SELECT a FROM t1 UNION ALL SELECT a FROM t3) q ORDER BY a;

--echo # Prepared statements
PREPARE stmt FROM "SELECT * FROM t1 UNION
  SELECT * FROM t2 ORDER BY 1";

EXECUTE stmt;
EXECUTE stmt;
EXECUTE stmt;

PREPARE stmt FROM "EXPLAIN SELECT * FROM t1 UNION
  SELECT * FROM t2 ORDER BY 1";

EXECUTE stmt;
EXECUTE stmt;

PREPARE stmt FROM "(SELECT * FROM t1 UNION
  SELECT * FROM t2) UNION ALL
  (SELECT * FROM t1 UNION
  SELECT * FROM t2) ORDER BY 1";

EXECUTE stmt;
EXECUTE stmt;
EXECUTE stmt;

PREPARE stmt FROM "EXPLAIN (SELECT * FROM t1 UNION
  SELECT * FROM t2) UNION ALL
  (SELECT * FROM t1 UNION
  SELECT * FROM t2) ORDER BY 1";

EXECUTE stmt;
EXECUTE stmt;

--echo # MCOL-5432 Disable UNION pushdown if an ORDER BY or a LIMIT
--echo # clause is involved, until MCOL-5222 is fixed.
SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY a;
EXPLAIN SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY a;
SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY a LIMIT 3;
EXPLAIN SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY a LIMIT 3;
SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY a DESC LIMIT 5;
EXPLAIN SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY a DESC LIMIT 5;
SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY a LIMIT 3 OFFSET 2;
EXPLAIN SELECT * FROM t1 UNION ALL SELECT * FROM t2 ORDER BY a LIMIT 3 OFFSET 2;

DELETE FROM t1; DELETE FROM t2; DELETE FROM t3; DELETE FROM t4;
INSERT INTO t1 VALUES ('1_abc'), ('3_bcd'), ('4_cde');
INSERT INTO t2 VALUES ('2_bcd'), ('5_cde'), ('6_def'), ('0_efg');
INSERT INTO t3 VALUES ('10_t3_myisam1'), ('11_t3_myisam2'), ('12_t3_myisam3');
INSERT INTO t4 VALUES ('20_t4_myisam1'), ('21_t4_myisam2'), ('22_t4_myisam3');

SELECT a FROM (SELECT a FROM t1 UNION SELECT a FROM t2) AS sub ORDER BY a ASC;
EXPLAIN SELECT a FROM (SELECT a FROM t1 UNION SELECT a FROM t2) AS sub ORDER BY a ASC;

SELECT a FROM (SELECT a FROM t1 UNION ALL SELECT a FROM t2) AS sub ORDER BY a DESC;
EXPLAIN SELECT a FROM (SELECT a FROM t1 UNION ALL SELECT a FROM t2) AS sub ORDER BY a DESC;

# multi-select chain
SELECT a FROM (SELECT a FROM t1 UNION SELECT a FROM t2 UNION ALL SELECT a FROM t3) AS sub ORDER BY a;
EXPLAIN SELECT a FROM (SELECT a FROM t1 UNION SELECT a FROM t2 UNION ALL SELECT a FROM t3) AS sub ORDER BY a;

# nested
SELECT a FROM ((SELECT a FROM t1 UNION SELECT a FROM t2) UNION ALL SELECT a FROM t3) AS sub ORDER BY a;
EXPLAIN SELECT a FROM ((SELECT a FROM t1 UNION SELECT a FROM t2) UNION ALL SELECT a FROM t3) AS sub ORDER BY a;

# aggregate
SELECT cnt FROM (SELECT COUNT(*) AS cnt FROM t1 UNION SELECT COUNT(*) AS cnt FROM t2) AS sub ORDER BY cnt;
EXPLAIN SELECT cnt FROM (SELECT COUNT(*) AS cnt FROM t1 UNION SELECT COUNT(*) AS cnt FROM t2) AS sub ORDER BY cnt;

# empty subquery result
DELETE FROM t1; DELETE FROM t2;
SELECT a FROM (SELECT a FROM t1 UNION SELECT a FROM t2) AS sub ORDER BY a;
EXPLAIN SELECT a FROM (SELECT a FROM t1 UNION SELECT a FROM t2) AS sub ORDER BY a;

DROP USER 'cejuser'@'localhost';
DROP TABLE t1, t2, t3, t4;
DROP DATABASE mdev25080;