我正在运行MacOS Catalina(10.15.3)，并在/usr/local/etc中找到my.cnf

In my case, the file did not exist. In MySQL Workbench I went to OPTIONS FILE and found some default values. I clicked apply. It asked for permission. It then created the my.cnf file under /etc. However, it is very important to keep in mind that the first time you click "apply", you do not make any changes to the default configuration. Once the file has been created, you can make changes which will be applied when you click "apply". Otherwise you will not be shown the apply button when you make changes.

将/usr/local/opt/mysql/support-files/my-default.cnf复制为/etc/my.cnf或/etc/mysql/my.cnf，然后重启mysql。

对于Mac，对我有用的是在我的~路径中创建一个.my.cnf文件。希望这能有所帮助。

我在macOS High Sierra 10.13.3版本中使用mysql 5.7.17版本，我在这里找到了mysql配置文件。

cd /usr/local/mysql/support-files/my-default.cnf

我不知道你使用的是哪个版本的MySQL，但以下是Mac OS X 5.5版本my.cnf文件的可能位置(从这里取):

/etc/my.cnf /etc/mysql/my.cnf SYSCONFDIR / my.cnf $ MYSQL_HOME / my.cnf Defaults-extra-file(使用——Defaults-extra-file =path指定的文件，如果有的话) ~ / .my.cnf