数据库主键性能对比：
名称 存储长度 生成方式
1. uuid 32+4 uuid()函数 2. uuid20 20 UUID_SHORT()函数 3. bigint自增 20 auto_increment
测试表：id_int（）、
-- uuid测试表
CREATE TABLE `id_uuid` (
`id` varchar(50) NOT NULL,
`name` varchar(100) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
-- uuid20测试表 【注：id是bigint unsigned 】
CREATE TABLE `id_uuid20` (
`id` bigint(20) unsigned NOT NULL,
`name` varchar(100) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
--int自增测试表（我本地使用的是int 可以改成bigint）
CREATE TABLE `id_int` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(100) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;
初始化100w条数据的存储过程：
-- 初始化int自增
CREATE PROCEDURE `int_init`(in s int)
BEGIN
DECLARE ct INT;
SET ct=1;
while ct<s DO
insert into id_int( name) VALUES ( concat('aaa',ct));
set ct=ct+1;
END WHILE;
END -- 初始化uuid20
CREATE PROCEDURE `uuid20_init`( in s int)
BEGIN
DECLARE ct INT;
SET ct=1;
while ct<s DO
insert into id_uuid20(id ,name) VALUES (uuid_short(), concat('aaa',ct));
set ct=ct+1;
END WHILE;
END -- 初始化uuid CREATE PROCEDURE `uuid_init`(in s int)
BEGIN
DECLARE ct INT;
SET ct=1;
while ct<s DO
insert into id_uuid (id, name) VALUES (uuid(), concat('aaa',ct));
set ct=ct+1;
END WHILE;
END -- 分别调用
call int_init(1000000); call uuid20_init(1000000); call uuid_init(1000000);
数据插入过程能发现int自增的插入速度明显高出另外两个，uuid()函数调用肯定没有自增快。不过相较于插入，我更关注查询的性能对比
count: 长整形的效率明显高于字符型的
mysql> select count(*) from id_int;
+----------+
| count(*) |
+----------+
| 2412382 |
+----------+
1 row in set (0.65 sec) mysql> select count(*) from id_uuid;
+----------+
| count(*) |
+----------+
| 1005356 |
+----------+
1 row in set (6.11 sec) mysql> select count(*) from id_uuid20;
+----------+
| count(*) |
+----------+
| 1000003 |
+----------+
1 row in set (0.82 sec)
基于主键查询：差别不大
mysql> select * from id_int where id = 555555;
+--------+-----------+
| id | name |
+--------+-----------+
| 555555 | aaa555538 |
+--------+-----------+
1 row in set (0.08 sec) mysql> select * from id_uuid where id ='e27267ba-a897-11e6-b4a0-742f68b93fab';
+--------------------------------------+-----------+
| id | name |
+--------------------------------------+-----------+
| e27267ba-a897-11e6-b4a0-742f68b93fab | aaa550010 |
+--------------------------------------+-----------+
1 row in set (0.02 sec) mysql> select * from id_uuid where id ='e27267ba-a897-11e6-b4a0-742f68b93fab';
+--------------------------------------+-----------+
| id | name |
+--------------------------------------+-----------+
| e27267ba-a897-11e6-b4a0-742f68b93fab | aaa550010 |
+--------------------------------------+-----------+
1 row in set (0.00 sec) mysql> select * from id_uuid20 where id = 24811291965678717;
+-------------------+-----------+
| id | name |
+-------------------+-----------+
| 24811291965678717 | aaa550010 |
+-------------------+-----------+
1 row in set (0.04 sec)
基于name查询（无索引）：
mysql> select * from id_int where name = 'aaa550010';
+--------+-----------+
| id | name |
+--------+-----------+
| 550027 | aaa550010 |
+--------+-----------+
1 row in set (0.93 sec) mysql> select * from id_uuid where name = 'aaa550010';
+--------------------------------------+-----------+
| id | name |
+--------------------------------------+-----------+
| e27267ba-a897-11e6-b4a0-742f68b93fab | aaa550010 |
+--------------------------------------+-----------+
1 row in set (6.36 sec) mysql> select * from id_uuid20 where name = 'aaa550010';
+-------------------+-----------+
| id | name |
+-------------------+-----------+
| 24811291965678717 | aaa550010 |
+-------------------+-----------+
1 row in set (0.82 sec)
加入索引后
mysql> select * from id_int where name = 'aaa550010';
+--------+-----------+
| id | name |
+--------+-----------+
| 550027 | aaa550010 |
+--------+-----------+
1 row in set (0.06 sec) mysql> select * from id_uuid where name = 'aaa550010';
+--------------------------------------+-----------+
| id | name |
+--------------------------------------+-----------+
| e27267ba-a897-11e6-b4a0-742f68b93fab | aaa550010 |
+--------------------------------------+-----------+
1 row in set (0.00 sec) mysql> select * from id_int where name = 'aaa550010';
+--------+-----------+
| id | name |
+--------+-----------+
| 550027 | aaa550010 |
+--------+-----------+
1 row in set (0.00 sec)
插入操作：
mysql> insert into id_int (name) values('ccccd');
Query OK, 1 row affected (0.02 sec)
mysql> insert into id_uuid20 (id,name) values(uuid_short(),'ccccc');
Query OK, 1 row affected (0.13 sec)
mysql> insert into id_uuid20 (id,name) values(uuid_short(),'cccc1');
Query OK, 1 row affected (0.06 sec)
mysql> insert into id_uuid20 (id,name) values(uuid_short(),'cccc3');
Query OK, 1 row affected (0.07 sec)
mysql> insert into id_int (name) values('cccc1');
Query OK, 1 row affected (0.02 sec)
mysql> insert into id_int (name) values('cccc2');
Query OK, 1 row affected (0.07 sec)
mysql> insert into id_int (name) values('cccc3');
Query OK, 1 row affected (0.07 sec)
mysql> insert into id_uuid20 (id,name) values(5231231231111111,'cccc4');
Query OK, 1 row affected (0.04 sec)
mysql> insert into id_uuid20 (id,name) values(5231231231111112,'cccc5');
Query OK, 1 row affected (0.02 sec)
mysql> insert into id_uuid20 (id,name) values(5531231231111112,'cccc5');
Query OK, 1 row affected (0.07 sec)
mysql> insert into id_uuid (id,name) values(uuid(),'cccc1');
Query OK, 1 row affected (0.07 sec)
mysql> insert into id_uuid (id,name) values(uuid(),'cccc2');
Query OK, 1 row affected (0.05 sec)
mysql> insert into id_uuid (id,name) values(uuid(),'cccc3');
Query OK, 1 row affected (0.03 sec)
mysql> insert into id_uuid (id,name) values('11cccasdqwdeqweqw','cccc4');
Query OK, 1 row affected (0.07 sec)
mysql> insert into id_uuid (id,name) values('12cccasdqwdeqweqw','cccc5');
Query OK, 1 row affected (0.07 sec)
参考：http://j2ees.iteye.com/blog/1554423