问题
As you can see from the output below, I'm using the MySQL shell to change the session's wait_timeout variable to 30 seconds. It works.
However, Is there anyway to set this variable from the command line?
$ mysql -u root -h 127.0.0.1 -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 48543
Server version: 5.6.39 MySQL Community Server (GPL)
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Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql> SHOW SESSION VARIABLES LIKE 'wait_timeout';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| wait_timeout | 28800 |
+---------------+-------+
1 row in set (0.00 sec)
mysql> SET session wait_timeout=30;
Query OK, 0 rows affected (0.00 sec)
mysql> SHOW SESSION VARIABLES LIKE 'wait_timeout';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| wait_timeout | 30 |
+---------------+-------+
1 row in set (0.00 sec)
mysql> select now() from dual;
+---------------------+
| now() |
+---------------------+
| 2018-01-23 17:16:52 |
+---------------------+
1 row in set (0.00 sec)
mysql> select now() from dual;
ERROR 2013 (HY000): Lost connection to MySQL server during query
回答1:
This does it:
$ mysql -u root -p -h 127.0.0.1 --init-command="SET SESSION wait_timeout=30"
来源：https://stackoverflow.com/questions/48407513/how-to-set-mysql-session-wait-timeout-from-the-command-line