在Linux系统下，我们可以通过命令行查看当前MySQL数据库的连接数。下面介绍两种方法。
方法一：
$ mysql -u username -pEnter password:mysql>status;--------------mysql Ver 14.14 Distrib 5.7.35, for Linux (x86_64) using EditLine wrapperConnection id: 12Current database:Current user: username@localhostSSL: Not in useCurrent pager: stdoutUsing outfile: ''Using delimiter: ;Server version: 5.7.35-0ubuntu0.18.04.1 (Ubuntu)Protocol version: 10Connection: localhost via UNIX socketServer characterset: utf8mb4Db characterset: utf8mb4Client characterset: utf8mb4Conn. characterset: utf8mb4UNIX socket: /var/run/mysqld/mysqld.sockUptime: 42 min 6 secThreads: 1 Questions: 1186 Slow queries: 0 Opens: 115 Flush tables: 1 Open tables: 60 Queries per second avg: 0.468--------------
上面的status命令可以查看当前连接数，如果是在客户端机器上，则需要安装MySQL客户端。
方法二：
$ mysqladmin -u username -p statusEnter password:Uptime: 2717 Threads: 9 Questions: 4406 Slow queries: 0 Opens: 50 Flush tables: 1 Open tables: 44 Queries per second avg: 1.621
这种方法不需要进入MySQL客户端，直接在命令行下执行即可。
