mysql - meaning of percent symbol in INFORMATION_SCHEMA.PROCESSLIST HOST column

Question

I'm running a query against INFORMATION_SCHEMA.PROCESSLIST (shown below). The HOST column in the result is showing %:port_number instead of ip_address:port_number.

select *
from INFORMATION_SCHEMA.PROCESSLIST
where 1=1
and COMMAND <> 'Sleep';

What is the meaning of the percent symbol (is it just, MySQL can't figure it out?), and why does it not show the incoming IP address?

Answer 1

'%' 字符是一个可以匹配任何主机的通配符。