MySQL的SLEEP()函数是否忙于等待？如何执行呢？
不，MySQL睡眠功能不忙于等待。让我们首先创建一个表并实现SLEEP()函数-
mysql> create table DemoTable(FirstName varchar(100));
使用插入命令在表中插入一些记录-
mysql> insert into DemoTable values('John');
mysql> insert into DemoTable values('Adam');
mysql> insert into DemoTable values('Bob');
mysql> insert into DemoTable values('Chris');
mysql> insert into DemoTable values('Robert');使用select语句显示表中的所有记录。我们还在SLEEP()这里设置了功能-
mysql> select sleep(10),FirstName from DemoTable;
这将产生以下输出-
+-----------+-----------+ | sleep(10) | FirstName | +-----------+-----------+ | 0 | John | | 0 | Adam | | 0 | Bob | | 0 | Chris | | 0 | Robert | +-----------+-----------+ 5 rows in set (50.00 sec)