DROP TABLE IF EXISTS t1, t2, t3, t4, t5;
CREATE TABLE t1 (c1 varchar(100)) ENGINE=MyISAM;
CREATE TABLE t2 (c1 varchar(100)) ENGINE=MyISAM;
CREATE TABLE t3 (c1 varchar(100)) ENGINE=InnoDB;
INSERT INTO t1 VALUES ('Ann'), ('Alice');
INSERT INTO t2 VALUES ('Bob'), ('Brian');
INSERT INTO t3 VALUES ('Chris'), ('Charlie');
CREATE TABLE t4 (c1 varchar(100)) ENGINE=MRG_MYISAM UNION=(t1,t2)
INSERT_METHOD=LAST;
CREATE TABLE t5 (c1 varchar(100)) ENGINE=MRG_MYISAM UNION=(t1,t3)
INSERT_METHOD=LAST;
SELECT * FROM t5;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
SELECT * FROM t4;
c1
Ann
Alice
Bob
Brian
ALTER TABLE t2 ENGINE=InnoDB;
SELECT * FROM t4;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
DELETE FROM t2 LIMIT 1;
SELECT * FROM t4;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
INSERT INTO t4 VALUES ('Beware');
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
SELECT * FROM t4;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
SELECT * FROM t2;
c1
Brian
SELECT * FROM t1;
c1
Ann
Alice
DROP TABLE t1, t2, t3, t4, t5;