1 row in set (0.00 sec) (7). unique_subquery 该类型替换了下面形式的IN子查询的ref: value IN (Select primary_key FROM single_table Where some_expr) unique_subquery是一个索引查找函数,可以完全替换子查询,效率更高。 (8).index_subquery 该联接类型类似于unique_subquery。可以替换IN子查询,但只适合...
And because linux computer ALWAYS generates at least some log files, killing cron can still fill the disk. Only way Cueball can win is if the problematic command is in /etc/crontab, the useful commands are in /etc/cron.d/ and adding mail to /etc/crontab will make cron ignore /etc/...
4.WHEN_FAILED =in_the_past 并且 TYPE=Old_age, 表示现在这个属性曾经出问题了. 但是现在是正常的. 为了避免这4种情况的发生. 1. 对于UPDATE=Offline的属性, 应该让smartd定期进行测试(smartd还可以发邮件). 或者crontab进行测试. 2. 应该时刻关注磁盘的Normalized value以及WORST的值是否接近THRESH的值了. 当...
[Linux System Administration ] - commands:reboot, exit, shutdown, date, mount, umount, ps, kill, systemctl, service, crontab [Linux Network Administration] - commands:curl, wget, telnet, ip, hostname, ifconfig, route, ssh, ssh-keygen, firewalld, iptables, host, nslookup, nc, netcat, ...