MySQL "show status" FAQ: Can you demonstrate how to use the MySQL show statuscommand to show MySQL variables and status information, such as the number of open MySQL connections?
I don‘t have a whole lot of time today to give this a detailed discussion, but here is a quick look at some MySQL work that I did recently to show MySQL open database connections.
MySQL show status - Open database connections
You can show MySQL open database connections (and other MySQL database parameters) using the MySQL show status command, like this:
mysql> show status like ‘Conn%‘; +---------------+-------+ | Variable_name | Value | +---------------+-------+ | Connections | 8 | +---------------+-------+ 1 row in set (0.00 sec) mysql> show status like ‘%onn%‘; +--------------------------+-------+ | Variable_name | Value | +--------------------------+-------+ | Aborted_connects | 0 | | Connections | 8 | | Max_used_connections | 4 | | Ssl_client_connects | 0 | | Ssl_connect_renegotiates | 0 | | Ssl_finished_connects | 0 | | Threads_connected | 4 | +--------------------------+-------+ 7 rows in set (0.00 sec)
All those rows and values that are printed out correspond to MySQL variables that you can look at. Notice that I use like ‘Conn%‘in the first example to show variables that look like "Connection", then got a little wiser in my second MySQL show status query.
MySQL show processlist
Here‘s what my MySQL processlist looks like when I had my Java application actively running under Tomcat:
mysql> show processlist; +----+------+-----------------+--------+---------+------+-------+------------------+ | Id | User | Host | db | Command | Time | State | Info | +----+------+-----------------+--------+---------+------+-------+------------------+ | 3 | root | localhost | webapp | Query | 0 | NULL | show processlist | | 5 | root | localhost:61704 | webapp | Sleep | 208 | | NULL | | 6 | root | localhost:61705 | webapp | Sleep | 208 | | NULL | | 7 | root | localhost:61706 | webapp | Sleep | 208 | | NULL | +----+------+-----------------+--------+---------+------+-------+------------------+ 4 rows in set (0.00 sec)
And here‘s what it looked like after I shut Tomcat down:
mysql> show processlist; +----+------+-----------+--------+---------+------+-------+------------------+ | Id | User | Host | db | Command | Time | State | Info | +----+------+-----------+--------+---------+------+-------+------------------+ | 3 | root | localhost | webapp | Query | 0 | NULL | show processlist | +----+------+-----------+--------+---------+------+-------+------------------+ 1 row in set (0.00 sec)
As a final note, you can also look at some MySQL variables using the mysqladmin command at the Unix/Linux command line, like this:
$ mysqladmin status Uptime: 4661 Threads: 1 Questions: 200 Slow queries: 0 Opens: 16 Flush tables: 1 Open tables: 6 Queries per second avg: 0.043
MySQL show status - Summary
Finally, here are two quick links to MySQL status pages:
I hope this brief look at the MySQL SHOW STATUS command has been helpful. As you can see, you can show information about a lot of MySQL status information, including the number of MySQL database connections, MySQL processes, and much more.
