[Architecture] MySQL Log File-Error Log

(I) What is it?

Records detailed information about MySQL server startup and shutdown, and severe warnings and errors during running.

mysql> show variables like 'log_error';+---------------+---------------------------------+| Variable_name | Value                           |+---------------+---------------------------------+| log_error     | /home/mysql/mysql/log/alert.log |+---------------+---------------------------------+1 row in set (0.01 sec)

For ease of maintenance, you may want to back up the content in the error log and record it again:

shell> mv host_name.err host_name.err-oldshell> mysqladmin flush-logsshell> mv host_name.err-old backup-directory

(Ii) What is the role?

MySQL DBA should first check this file when encountering problems
When MySQL server cannot be started normally, the first target of torture should be this person.

The Error Log File in MySQL has similar functions as alert in Oracle.
However, we can see from the name that MySQL is still tender.
The error logs is not all error information, and not all errors are recorded in the log. This name is a bit out of the real name.
Or Oracle Gaoming-alert, is to remind you to pay attention to, understand nothing wrong