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|
set global storage_engine=myisam;
set session storage_engine=myisam;
drop table if exists t1,t2,t3,t4,t5,t6;
drop database if exists mysqltest;
create table t1 (a int not null primary key auto_increment, message char(20));
create table t2 (a int not null primary key auto_increment, message char(20));
INSERT INTO t1 (message) VALUES ("Testing"),("table"),("t1");
INSERT INTO t2 (message) VALUES ("Testing"),("table"),("t2");
create table t3 (a int not null, b char(20), key(a)) engine=MERGE UNION=(t1,t2);
select * from t3;
a b
1 Testing
2 table
3 t1
1 Testing
2 table
3 t2
select * from t3 order by a desc;
a b
3 t1
3 t2
2 table
2 table
1 Testing
1 Testing
drop table t3;
insert into t1 select NULL,message from t2;
insert into t2 select NULL,message from t1;
insert into t1 select NULL,message from t2;
insert into t2 select NULL,message from t1;
insert into t1 select NULL,message from t2;
insert into t2 select NULL,message from t1;
insert into t1 select NULL,message from t2;
insert into t2 select NULL,message from t1;
insert into t1 select NULL,message from t2;
insert into t2 select NULL,message from t1;
insert into t1 select NULL,message from t2;
create table t3 (a int not null, b char(20), key(a)) engine=MERGE UNION=(test.t1,test.t2);
explain select * from t3 where a < 10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t3 range a a 4 NULL 18 Using where
explain select * from t3 where a > 10 and a < 20;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t3 range a a 4 NULL 17 Using where
select * from t3 where a = 10;
a b
10 Testing
10 Testing
select * from t3 where a < 10;
a b
1 Testing
1 Testing
2 table
2 table
3 t1
3 t2
4 Testing
4 Testing
5 table
5 table
6 t2
6 t1
7 Testing
7 Testing
8 table
8 table
9 t2
9 t2
select * from t3 where a > 10 and a < 20;
a b
11 table
11 table
12 t1
12 t1
13 Testing
13 Testing
14 table
14 table
15 t2
15 t2
16 Testing
16 Testing
17 table
17 table
18 t2
18 t2
19 Testing
19 Testing
explain select a from t3 order by a desc limit 10;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t3 index NULL a 4 NULL 10 Using index
select a from t3 order by a desc limit 10;
a
699
698
697
696
695
694
693
692
691
690
select a from t3 order by a desc limit 300,10;
a
416
415
415
414
414
413
413
412
412
411
delete from t3 where a=3;
select * from t3 where a < 10;
a b
1 Testing
1 Testing
2 table
2 table
4 Testing
4 Testing
5 table
5 table
6 t2
6 t1
7 Testing
7 Testing
8 table
8 table
9 t2
9 t2
delete from t3 where a >= 6 and a <= 8;
select * from t3 where a < 10;
a b
1 Testing
1 Testing
2 table
2 table
4 Testing
4 Testing
5 table
5 table
9 t2
9 t2
update t3 set a=3 where a=9;
select * from t3 where a < 10;
a b
1 Testing
1 Testing
2 table
2 table
3 t2
3 t2
4 Testing
4 Testing
5 table
5 table
update t3 set a=6 where a=7;
select * from t3 where a < 10;
a b
1 Testing
1 Testing
2 table
2 table
3 t2
3 t2
4 Testing
4 Testing
5 table
5 table
show create table t3;
Table Create Table
t3 CREATE TABLE `t3` (
`a` int(11) NOT NULL,
`b` char(20) DEFAULT NULL,
KEY `a` (`a`)
) ENGINE=MRG_MyISAM DEFAULT CHARSET=latin1 UNION=(`t1`,`t2`)
create table t4 (a int not null, b char(10), key(a)) engine=MERGE UNION=(t1,t2);
select * from t4;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
alter table t4 add column c int;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
flush tables;
select * from t4;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
create database mysqltest;
create table mysqltest.t6 (a int not null primary key auto_increment, message char(20));
create table t5 (a int not null, b char(20), key(a)) engine=MERGE UNION=(test.t1,mysqltest.t6);
show create table t5;
Table Create Table
t5 CREATE TABLE `t5` (
`a` int(11) NOT NULL,
`b` char(20) DEFAULT NULL,
KEY `a` (`a`)
) ENGINE=MRG_MyISAM DEFAULT CHARSET=latin1 UNION=(`t1`,`mysqltest`.`t6`)
alter table t5 engine=myisam;
drop table t5, mysqltest.t6;
drop database mysqltest;
drop table t4,t3,t1,t2;
create table t1 (c char(10)) engine=myisam;
create table t2 (c char(10)) engine=myisam;
create table t3 (c char(10)) union=(t1,t2) engine=merge;
insert into t1 (c) values ('test1');
insert into t1 (c) values ('test1');
insert into t1 (c) values ('test1');
insert into t2 (c) values ('test2');
insert into t2 (c) values ('test2');
insert into t2 (c) values ('test2');
select * from t3;
c
test1
test1
test1
test2
test2
test2
select * from t3;
c
test1
test1
test1
test2
test2
test2
delete from t3 where 1=1;
select * from t3;
c
select * from t1;
c
drop table t3,t2,t1;
CREATE TABLE t1 (incr int not null, othr int not null, primary key(incr));
CREATE TABLE t2 (incr int not null, othr int not null, primary key(incr));
CREATE TABLE t3 (incr int not null, othr int not null, primary key(incr))
ENGINE=MERGE UNION=(t1,t2);
SELECT * from t3;
incr othr
INSERT INTO t1 VALUES ( 1,10),( 3,53),( 5,21),( 7,12),( 9,17);
INSERT INTO t2 VALUES ( 2,24),( 4,33),( 6,41),( 8,26),( 0,32);
INSERT INTO t1 VALUES (11,20),(13,43),(15,11),(17,22),(19,37);
INSERT INTO t2 VALUES (12,25),(14,31),(16,42),(18,27),(10,30);
SELECT * from t3 where incr in (1,2,3,4) order by othr;
incr othr
1 10
2 24
4 33
3 53
alter table t3 UNION=(t1);
select count(*) from t3;
count(*)
10
alter table t3 UNION=(t1,t2);
select count(*) from t3;
count(*)
20
alter table t3 ENGINE=MYISAM;
select count(*) from t3;
count(*)
20
drop table t3;
CREATE TABLE t3 (incr int not null, othr int not null, primary key(incr))
ENGINE=MERGE UNION=(t1,t2);
show create table t3;
Table Create Table
t3 CREATE TABLE `t3` (
`incr` int(11) NOT NULL,
`othr` int(11) NOT NULL,
PRIMARY KEY (`incr`)
) ENGINE=MRG_MyISAM DEFAULT CHARSET=latin1 UNION=(`t1`,`t2`)
alter table t3 drop primary key;
show create table t3;
Table Create Table
t3 CREATE TABLE `t3` (
`incr` int(11) NOT NULL,
`othr` int(11) NOT NULL
) ENGINE=MRG_MyISAM DEFAULT CHARSET=latin1 UNION=(`t1`,`t2`)
drop table t3,t2,t1;
create table t1 (a int not null, key(a)) engine=merge;
select * from t1;
ERROR HY000: Got error 124 from storage engine
drop table t1;
create table t1 (a int not null, b int not null, key(a,b));
create table t2 (a int not null, b int not null, key(a,b));
create table t3 (a int not null, b int not null, key(a,b)) ENGINE=MERGE UNION=(t1,t2);
insert into t1 values (1,2),(2,1),(0,0),(4,4),(5,5),(6,6);
insert into t2 values (1,1),(2,2),(0,0),(4,4),(5,5),(6,6);
flush tables;
select * from t3 where a=1 order by b limit 2;
a b
1 1
1 2
drop table t3,t1,t2;
create table t1 (a int not null, b int not null auto_increment, primary key(a,b));
create table t2 (a int not null, b int not null auto_increment, primary key(a,b));
create table t3 (a int not null, b int not null, key(a,b)) UNION=(t1,t2) INSERT_METHOD=NO;
create table t4 (a int not null, b int not null, key(a,b)) ENGINE=MERGE UNION=(t1,t2) INSERT_METHOD=NO;
create table t5 (a int not null, b int not null auto_increment, primary key(a,b)) ENGINE=MERGE UNION=(t1,t2) INSERT_METHOD=FIRST;
create table t6 (a int not null, b int not null auto_increment, primary key(a,b)) ENGINE=MERGE UNION=(t1,t2) INSERT_METHOD=LAST;
show create table t3;
Table Create Table
t3 CREATE TABLE `t3` (
`a` int(11) NOT NULL,
`b` int(11) NOT NULL,
KEY `a` (`a`,`b`)
) ENGINE=MyISAM DEFAULT CHARSET=latin1
show create table t4;
Table Create Table
t4 CREATE TABLE `t4` (
`a` int(11) NOT NULL,
`b` int(11) NOT NULL,
KEY `a` (`a`,`b`)
) ENGINE=MRG_MyISAM DEFAULT CHARSET=latin1 UNION=(`t1`,`t2`)
show create table t5;
Table Create Table
t5 CREATE TABLE `t5` (
`a` int(11) NOT NULL,
`b` int(11) NOT NULL AUTO_INCREMENT,
PRIMARY KEY (`a`,`b`)
) ENGINE=MRG_MyISAM DEFAULT CHARSET=latin1 INSERT_METHOD=FIRST UNION=(`t1`,`t2`)
show create table t6;
Table Create Table
t6 CREATE TABLE `t6` (
`a` int(11) NOT NULL,
`b` int(11) NOT NULL AUTO_INCREMENT,
PRIMARY KEY (`a`,`b`)
) ENGINE=MRG_MyISAM DEFAULT CHARSET=latin1 INSERT_METHOD=LAST UNION=(`t1`,`t2`)
insert into t1 values (1,NULL),(1,NULL),(1,NULL),(1,NULL);
insert into t2 values (2,NULL),(2,NULL),(2,NULL),(2,NULL);
select * from t3 order by b,a limit 3;
a b
select * from t4 order by b,a limit 3;
a b
1 1
2 1
1 2
select * from t5 order by b,a limit 3,3;
a b
2 2
1 3
2 3
select * from t6 order by b,a limit 6,3;
a b
1 4
2 4
insert into t5 values (5,1),(5,2);
insert into t6 values (6,1),(6,2);
select * from t1 order by a,b;
a b
1 1
1 2
1 3
1 4
5 1
5 2
select * from t2 order by a,b;
a b
2 1
2 2
2 3
2 4
6 1
6 2
select * from t4 order by a,b;
a b
1 1
1 2
1 3
1 4
2 1
2 2
2 3
2 4
5 1
5 2
6 1
6 2
insert into t3 values (3,1),(3,2),(3,3),(3,4);
select * from t3 order by a,b;
a b
3 1
3 2
3 3
3 4
alter table t4 UNION=(t1,t2,t3);
show create table t4;
Table Create Table
t4 CREATE TABLE `t4` (
`a` int(11) NOT NULL,
`b` int(11) NOT NULL,
KEY `a` (`a`,`b`)
) ENGINE=MRG_MyISAM DEFAULT CHARSET=latin1 UNION=(`t1`,`t2`,`t3`)
select * from t4 order by a,b;
a b
1 1
1 2
1 3
1 4
2 1
2 2
2 3
2 4
3 1
3 2
3 3
3 4
5 1
5 2
6 1
6 2
alter table t4 INSERT_METHOD=FIRST;
show create table t4;
Table Create Table
t4 CREATE TABLE `t4` (
`a` int(11) NOT NULL,
`b` int(11) NOT NULL,
KEY `a` (`a`,`b`)
) ENGINE=MRG_MyISAM DEFAULT CHARSET=latin1 INSERT_METHOD=FIRST UNION=(`t1`,`t2`,`t3`)
insert into t4 values (4,1),(4,2);
select * from t1 order by a,b;
a b
1 1
1 2
1 3
1 4
4 1
4 2
5 1
5 2
select * from t2 order by a,b;
a b
2 1
2 2
2 3
2 4
6 1
6 2
select * from t3 order by a,b;
a b
3 1
3 2
3 3
3 4
select * from t4 order by a,b;
a b
1 1
1 2
1 3
1 4
2 1
2 2
2 3
2 4
3 1
3 2
3 3
3 4
4 1
4 2
5 1
5 2
6 1
6 2
select * from t5 order by a,b;
a b
1 1
1 2
1 3
1 4
2 1
2 2
2 3
2 4
4 1
4 2
5 1
5 2
6 1
6 2
select 1;
1
1
insert into t5 values (1,NULL),(5,NULL);
insert into t6 values (2,NULL),(6,NULL);
select * from t1 order by a,b;
a b
1 1
1 2
1 3
1 4
1 5
4 1
4 2
5 1
5 2
5 3
select * from t2 order by a,b;
a b
2 1
2 2
2 3
2 4
2 5
6 1
6 2
6 3
select * from t5 order by a,b;
a b
1 1
1 2
1 3
1 4
1 5
2 1
2 2
2 3
2 4
2 5
4 1
4 2
5 1
5 2
5 3
6 1
6 2
6 3
select * from t6 order by a,b;
a b
1 1
1 2
1 3
1 4
1 5
2 1
2 2
2 3
2 4
2 5
4 1
4 2
5 1
5 2
5 3
6 1
6 2
6 3
insert into t1 values (99,NULL);
select * from t4 where a+0 > 90;
a b
99 1
insert t5 values (1,1);
ERROR 23000: Duplicate entry '1-1' for key 'PRIMARY'
insert t6 values (2,1);
ERROR 23000: Duplicate entry '2-1' for key 'PRIMARY'
insert t5 values (1,1) on duplicate key update b=b+10;
insert t6 values (2,1) on duplicate key update b=b+20;
select * from t5 where a < 3;
a b
1 2
1 3
1 4
1 5
1 11
2 2
2 3
2 4
2 5
2 21
drop table t6, t5, t4, t3, t2, t1;
CREATE TABLE t1 ( a int(11) NOT NULL default '0', b int(11) NOT NULL default '0', PRIMARY KEY (a,b)) ENGINE=MyISAM;
INSERT INTO t1 VALUES (1,1), (2,1);
CREATE TABLE t2 ( a int(11) NOT NULL default '0', b int(11) NOT NULL default '0', PRIMARY KEY (a,b)) ENGINE=MyISAM;
INSERT INTO t2 VALUES (1,2), (2,2);
CREATE TABLE t3 ( a int(11) NOT NULL default '0', b int(11) NOT NULL default '0', KEY a (a,b)) ENGINE=MRG_MyISAM UNION=(t1,t2);
select max(b) from t3 where a = 2;
max(b)
2
select max(b) from t1 where a = 2;
max(b)
1
drop table t3,t1,t2;
create table t1 (a int not null);
create table t2 (a int not null);
insert into t1 values (1);
insert into t2 values (2);
create temporary table t3 (a int not null) ENGINE=MERGE UNION=(t1,t2);
select * from t3;
a
1
2
create temporary table t4 (a int not null);
create temporary table t5 (a int not null);
insert into t4 values (1);
insert into t5 values (2);
create temporary table t6 (a int not null) ENGINE=MERGE UNION=(t4,t5);
select * from t6;
a
1
2
drop table t6, t3, t1, t2, t4, t5;
CREATE TABLE t1 (
fileset_id tinyint(3) unsigned NOT NULL default '0',
file_code varchar(32) NOT NULL default '',
fileset_root_id tinyint(3) unsigned NOT NULL default '0',
PRIMARY KEY (fileset_id,file_code),
KEY files (fileset_id,fileset_root_id)
) ENGINE=MyISAM;
INSERT INTO t1 VALUES (2, '0000000111', 1), (2, '0000000112', 1), (2, '0000000113', 1),
(2, '0000000114', 1), (2, '0000000115', 1), (2, '0000000116', 1), (2, '0000000117', 1),
(2, '0000000118', 1), (2, '0000000119', 1), (2, '0000000120', 1);
CREATE TABLE t2 (
fileset_id tinyint(3) unsigned NOT NULL default '0',
file_code varchar(32) NOT NULL default '',
fileset_root_id tinyint(3) unsigned NOT NULL default '0',
PRIMARY KEY (fileset_id,file_code),
KEY files (fileset_id,fileset_root_id)
) ENGINE=MRG_MyISAM UNION=(t1);
EXPLAIN SELECT * FROM t2 IGNORE INDEX (files) WHERE fileset_id = 2
AND file_code BETWEEN '0000000115' AND '0000000120' LIMIT 1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 range PRIMARY PRIMARY 35 NULL 5 Using where
EXPLAIN SELECT * FROM t2 WHERE fileset_id = 2
AND file_code BETWEEN '0000000115' AND '0000000120' LIMIT 1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 range PRIMARY,files PRIMARY 35 NULL 5 Using where
EXPLAIN SELECT * FROM t1 WHERE fileset_id = 2
AND file_code BETWEEN '0000000115' AND '0000000120' LIMIT 1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 range PRIMARY,files PRIMARY 35 NULL 5 Using where
EXPLAIN SELECT * FROM t2 WHERE fileset_id = 2
AND file_code = '0000000115' LIMIT 1;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 const PRIMARY,files PRIMARY 35 const,const 1
DROP TABLE t2, t1;
create table t1 (x int, y int, index xy(x, y));
create table t2 (x int, y int, index xy(x, y));
create table t3 (x int, y int, index xy(x, y)) engine=merge union=(t1,t2);
insert into t1 values(1, 2);
insert into t2 values(1, 3);
select * from t3 where x = 1 and y < 5 order by y;
x y
1 2
1 3
select * from t3 where x = 1 and y < 5 order by y desc;
x y
1 3
1 2
drop table t1,t2,t3;
create table t1 (a int);
create table t2 (a int);
insert into t1 values (0);
insert into t2 values (1);
create table t3 engine=merge union=(t1, t2) select * from t1;
ERROR HY000: You can't specify target table 't1' for update in FROM clause
create table t3 engine=merge union=(t1, t2) select * from t2;
ERROR HY000: You can't specify target table 't2' for update in FROM clause
create table t3 engine=merge union=(t1, t2) select (select max(a) from t2);
ERROR HY000: You can't specify target table 't2' for update in FROM clause
drop table t1, t2;
create table t1 (
a double(14,4),
b varchar(10),
index (a,b)
) engine=merge union=(t2,t3);
create table t2 (
a double(14,4),
b varchar(10),
index (a,b)
) engine=myisam;
create table t3 (
a double(14,4),
b varchar(10),
index (a,b)
) engine=myisam;
insert into t2 values ( null, '');
insert into t2 values ( 9999999999.999, '');
insert into t3 select * from t2;
select min(a), max(a) from t1;
min(a) max(a)
9999999999.9990 9999999999.9990
flush tables;
select min(a), max(a) from t1;
min(a) max(a)
9999999999.9990 9999999999.9990
drop table t1, t2, t3;
create table t1 (a int,b int,c int, index (a,b,c));
create table t2 (a int,b int,c int, index (a,b,c));
create table t3 (a int,b int,c int, index (a,b,c))
engine=merge union=(t1 ,t2);
insert into t1 (a,b,c) values (1,1,0),(1,2,0);
insert into t2 (a,b,c) values (1,1,1),(1,2,1);
explain select a,b,c from t3 force index (a) where a=1 order by a,b,c;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t3 ref a a 5 const 2 Using where; Using index
select a,b,c from t3 force index (a) where a=1 order by a,b,c;
a b c
1 1 0
1 1 1
1 2 0
1 2 1
explain select a,b,c from t3 force index (a) where a=1 order by a desc, b desc, c desc;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t3 ref a a 5 const 2 Using where; Using index
select a,b,c from t3 force index (a) where a=1 order by a desc, b desc, c desc;
a b c
1 2 1
1 2 0
1 1 1
1 1 0
show index from t3;
Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment
t3 1 a 1 a A NULL NULL NULL YES BTREE
t3 1 a 2 b A NULL NULL NULL YES BTREE
t3 1 a 3 c A NULL NULL NULL YES BTREE
drop table t1, t2, t3;
CREATE TABLE t1 ( a INT AUTO_INCREMENT PRIMARY KEY, b VARCHAR(10), UNIQUE (b) )
ENGINE=MyISAM;
CREATE TABLE t2 ( a INT AUTO_INCREMENT, b VARCHAR(10), INDEX (a), INDEX (b) )
ENGINE=MERGE UNION (t1) INSERT_METHOD=FIRST;
INSERT INTO t2 (b) VALUES (1) ON DUPLICATE KEY UPDATE b=2;
INSERT INTO t2 (b) VALUES (1) ON DUPLICATE KEY UPDATE b=3;
SELECT b FROM t2;
b
3
DROP TABLE t1, t2;
create table t1(a int);
create table t2(a int);
insert into t1 values (1);
insert into t2 values (2);
create table t3 (a int) engine=merge union=(t1, t2) insert_method=first;
select * from t3;
a
1
2
insert t2 select * from t2;
select * from t2;
a
2
2
insert t3 select * from t1;
select * from t3;
a
1
1
2
2
insert t1 select * from t3;
select * from t1;
a
1
1
1
1
2
2
select * from t2;
a
2
2
select * from t3;
a
1
1
1
1
2
2
2
2
check table t1, t2;
Table Op Msg_type Msg_text
test.t1 check status OK
test.t2 check status OK
drop table t1, t2, t3;
CREATE TABLE t1(a INT);
INSERT INTO t1 VALUES(2),(1);
CREATE TABLE t2(a INT, KEY(a)) ENGINE=MERGE UNION=(t1);
SELECT * FROM t2 WHERE a=2;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
DROP TABLE t1, t2;
CREATE TABLE t1(a INT) ENGINE=MEMORY;
CREATE TABLE t2(a INT) ENGINE=MERGE UNION=(t1);
SELECT * FROM t2;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
DROP TABLE t1, t2;
CREATE TABLE t2(a INT) ENGINE=MERGE UNION=(t3);
SELECT * FROM t2;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
DROP TABLE t2;
CREATE TABLE t1(a INT, b TEXT);
CREATE TABLE tm1(a TEXT, b INT) ENGINE=MERGE UNION=(t1);
SELECT * FROM tm1;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
DROP TABLE t1, tm1;
CREATE TABLE t1(a SMALLINT, b SMALLINT);
CREATE TABLE tm1(a INT) ENGINE=MERGE UNION=(t1);
SELECT * FROM tm1;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
DROP TABLE t1, tm1;
CREATE TABLE t1(a SMALLINT, b SMALLINT, KEY(a, b));
CREATE TABLE tm1(a SMALLINT, b SMALLINT, KEY(a)) ENGINE=MERGE UNION=(t1);
SELECT * FROM tm1;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
DROP TABLE t1, tm1;
CREATE TABLE t1(a SMALLINT, b SMALLINT, KEY(b));
CREATE TABLE tm1(a SMALLINT, b SMALLINT, KEY(a)) ENGINE=MERGE UNION=(t1);
SELECT * FROM tm1;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
DROP TABLE t1, tm1;
CREATE TABLE t1(c1 VARCHAR(1));
CREATE TABLE m1 LIKE t1;
ALTER TABLE m1 ENGINE=MERGE UNION=(t1);
SELECT * FROM m1;
c1
DROP TABLE t1, m1;
CREATE TABLE t1(c1 VARCHAR(4), c2 TINYINT, c3 TINYINT, c4 TINYINT,
c5 TINYINT, c6 TINYINT, c7 TINYINT, c8 TINYINT, c9 TINYINT);
CREATE TABLE m1 LIKE t1;
ALTER TABLE m1 ENGINE=MERGE UNION=(t1);
SELECT * FROM m1;
c1 c2 c3 c4 c5 c6 c7 c8 c9
DROP TABLE t1, m1;
CREATE TABLE t1 (a VARCHAR(255) CHARACTER SET latin1 COLLATE latin1_german2_ci,
b INT, INDEX(a,b));
CREATE TABLE t2 LIKE t1;
CREATE TABLE t3 LIKE t1;
ALTER TABLE t3 ENGINE=MERGE UNION=(t1,t2);
INSERT INTO t1 VALUES ('ss',1);
INSERT INTO t2 VALUES ('ss',2),(0xDF,2);
SELECT COUNT(*) FROM t3 WHERE a=0xDF AND b=2;
COUNT(*)
2
DROP TABLE t1,t2,t3;
create table t1 (b bit(1));
create table t2 (b bit(1));
create table tm (b bit(1)) engine = merge union = (t1,t2);
select * from tm;
b
drop table tm, t1, t2;
create table t1 (a int) insert_method = last engine = merge;
insert into t1 values (1);
ERROR HY000: Table 't1' is read only
create table t2 (a int) engine = myisam;
alter table t1 union (t2);
insert into t1 values (1);
alter table t1 insert_method = no;
insert into t1 values (1);
ERROR HY000: Table 't1' is read only
drop table t2;
drop table t1;
CREATE TABLE tm1(a INT) ENGINE=MERGE UNION=(t1, t2);
SELECT * FROM tm1;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
CHECK TABLE tm1;
Table Op Msg_type Msg_text
test.tm1 check Error Table 'test.t1' is differently defined or of non-MyISAM type or doesn't exist
test.tm1 check Error Table 'test.t2' is differently defined or of non-MyISAM type or doesn't exist
test.tm1 check Error Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
test.tm1 check error Corrupt
CREATE TABLE t1(a INT);
SELECT * FROM tm1;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
CHECK TABLE tm1;
Table Op Msg_type Msg_text
test.tm1 check Error Table 'test.t2' is differently defined or of non-MyISAM type or doesn't exist
test.tm1 check Error Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
test.tm1 check error Corrupt
CREATE TABLE t2(a BLOB);
SELECT * FROM tm1;
ERROR HY000: Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
CHECK TABLE tm1;
Table Op Msg_type Msg_text
test.tm1 check Error Table 'test.t2' is differently defined or of non-MyISAM type or doesn't exist
test.tm1 check Error Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist
test.tm1 check error Corrupt
ALTER TABLE t2 MODIFY a INT;
SELECT * FROM tm1;
a
CHECK TABLE tm1;
Table Op Msg_type Msg_text
test.tm1 check status OK
DROP TABLE tm1, t1, t2;
End of 5.0 tests
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