merge.result

这是linux下运行的mysql软件包,可用于linux 下安装 php + mysql + apach 的网络配置

  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 1
insert t6 values (2,1);
ERROR 23000: Duplicate entry '2-1' for key 1
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	ref	PRIMARY,files	PRIMARY	35	const,const	1	Using where
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;