mysql有没有一个算法生成一个特定id
随机生成id
没什么好办法,一种常见方法是,利用RAND随机函数生成一个,然后检查一下是否已经存在,如是存在则继续随机,直至找到一个不存在的。
mysql> select cast(rand()*100 as SIGNED );
+—————————–+
| cast(rand()*100 as SIGNED ) |
+—————————–+
| 44 |
+—————————–+
1 row in set (0.01 sec)
mysql> select cast(rand()*100 as SIGNED );
+—————————–+
| cast(rand()*100 as SIGNED ) |
+—————————–+
| 27 |
+—————————–+
1 row in set (0.00 sec)
mysql> select cast(rand()*100 as SIGNED );
+—————————–+
| cast(rand()*100 as SIGNED ) |
+—————————–+
| 1 |
+—————————–+
1 row in set (0.00 sec)