mysql各版本在线增加与删除字段

 最近测试了mysql各版本在线增加和删除操作，mysql5.1与mysql5.5无论是myisam还是innodb，增加删除字段时，可进行查询操作，修改操作将锁表，而发现mysql5.6的innodb支持查询和更新，在块mysql5.6做的很强大，另外infobright的增加和删除列操作几乎瞬间完成，这也得益于他是列式存储的关系。

以下是我的测试过程：

mysql5.1：增加和删除字段时只能执行查询，修改操作将会锁表。
mysql> alter table test1 add id2 int;
Query OK, 33554434 rows affected (36.01 sec)
Records: 33554434 Duplicates: 0 Warnings: 0

mysql> select count(*) from test1;
+----------+
| count(*) |
+----------+
| 33554435 |
+----------+
1 row in set (0.00 sec)

mysql> insert into test1(id) values(1);
Query OK, 1 row affected (32.44 sec)

mysql> show processlist;
+----+------+-----------+------+---------+------+-------------------+---------------------------------+
| Id | User | Host | db | Command | Time | State | Info |
+----+------+-----------+------+---------+------+-------------------+---------------------------------+
| 1 | root | localhost | test | Query | 11 | copy to tmp table | alter table test1 add id2 int |
| 2 | root | localhost | test | Query | 7 | Locked | insert into test1(id) values(1) |
| 3 | root | localhost | NULL | Query | 0 | NULL | show processlist |
+----+------+-----------+------+---------+------+-------------------+---------------------------------+

mysql5.5：增加和删除字段时只能执行查询，修改操作将会锁表。
mysql> alter table test add id3 int;
Query OK, 8388608 rows affected (1 min 11.55 sec)
Records: 8388608 Duplicates: 0 Warnings: 0

mysql> select * from test limit 1;
+------+--------------------------------------+
| id | id1 |
+------+--------------------------------------+
| 1 | bbab3146-87ba-11e2-8238-782bcb0561d1 |
+------+--------------------------------------+
1 row in set (0.00 sec)

mysql> insert into test values(1,uuid());
ERROR 1136 (21S01): Column count doesn't match value count at row 1

mysql> show processlist;
+----+------+-----------+------+---------+------+---------------------------------+-----------------------------------+
| Id | User | Host | db | Command | Time | State | Info |
+----+------+-----------+------+---------+------+---------------------------------+-----------------------------------+
| 1 | root | localhost | test | Query | 40 | copy to tmp table | alter table test add id3 int |
| 2 | root | localhost | test | Query | 25 | Waiting for table metadata lock | insert into test values(1,uuid()) |
| 3 | root | localhost | NULL | Query | 0 | NULL | show processlist |
+----+------+-----------+------+---------+------+---------------------------------+-----------------------------------+

mysql5.6
INNODB：增加字段时，能在线执行查询与修改操作
CREATE TABLE `sbtest` (
`id` int(10) unsigned NOT NULL AUTO_INCREMENT,
`k` int(10) unsigned NOT NULL DEFAULT '0',
`c` char(120) NOT NULL DEFAULT '',
`pad` char(60) NOT NULL DEFAULT '',
PRIMARY KEY (`id`),
KEY `k` (`k`)
) ENGINE=InnoDB AUTO_INCREMENT=10000001 DEFAULT CHARSET=latin1 |

mysql> alter table sbtest add column id1 int;
Query OK, 0 rows affected (4 min 45.54 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> select count(*) from sbtest;
+----------+
| count(*) |
+----------+
| 10000000 |
+----------+
1 row in set (3.20 sec)

mysql> insert into sbtest(id) values(1000000000);
Query OK, 1 row affected (0.01 sec)

mysql> delete from sbtest where id=1000000000;
Query OK, 1 row affected (0.77 sec)

mysql> update sbtest set k=1 where k=1000000000;
Query OK, 1 row affected (0.05 sec)
Rows matched: 1 Changed: 1 Warnings: 0

myisam：增加字段时，只能在线执行查询操作，修改操作将锁表
mysql> alter table test add id3 int;
Query OK, 33554434 rows affected (12.41 sec)
Records: 33554434 Duplicates: 0 Warnings: 0

mysql> select * from test limit 1;
+------+--------------------------------------+
| id | id1 |
+------+--------------------------------------+
| 1 | 4f6d81ae-87bb-11e2-8da9-782bcb0561d1 |
+------+--------------------------------------+
1 row in set (0.00 sec)

mysql> insert into test(id) values(2);
Query OK, 1 row affected (10.75 sec)

mysql> show processlist;
+----+------+-----------+------+---------+------+---------------------------------+--------------------------------+
| Id | User | Host | db | Command | Time | State | Info |
+----+------+-----------+------+---------+------+---------------------------------+--------------------------------+
| 43 | root | localhost | test | Query | 2 | Waiting for table metadata lock | insert into test(id) values(2) |
| 45 | root | localhost | test | Query | 3 | copy to tmp table | alter table test add id3 int |
| 46 | root | localhost | NULL | Query | 0 | init | show processlist |
+----+------+-----------+------+---------+------+---------------------------------+--------------------------------+

infobright：能快速的增加和删除列
mysql> select count(*) from test;
+----------+
| count(*) |
+----------+
| 67108864 |
+----------+
1 row in set (0.00 sec)

mysql> alter table test add id2 int;
Query OK, 0 rows affected (0.93 sec)
Records: 0 Duplicates: 0 Warnings: 0

mysql> alter table test drop column id2 ;
Query OK, 0 rows affected (0.01 sec)
Records: 0 Duplicates: 0 Warnings: 0

转载于:https://blog.51cto.com/chen122301/1150200