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.

通常，在Unix和类Unix系统上，MySQL/MariaDB程序在以下位置读取配置/启动文件(按指定顺序):

/etc/my.cnf - Global /etc/mysql/my.cnf - Global SYSCONFDIR/my.cnf - Global SYSCONFDIR represents the directory specified with the SYSCONFDIR option to CMake when MySQL was built. By default, this is the etc directory located under the compiled-in installation directory. $MYSQL_HOME/my.cnf - Server-specific (server only) MYSQL_HOME is an environment variable containing the path to the directory in which the server-specific my.cnf file resides. If MYSQL_HOME is not set and you start the server using the mysqld_safe program, mysqld_safe sets it to BASEDIR, the MySQL base installation directory. file specified with --defaults-extra-file=path if any ~/.my.cnf - User-specific ~/.mylogin.cnf - User-specific (clients only)

来源:使用选项文件。

注意:在Unix平台上，MySQL忽略全局可写的配置文件。这是有意为之的安全措施。

此外，在Mac上有一个简单的方法来检查它。

执行命令sudo fs_usage | grep my.cnf 这将实时报告与该文件相关的任何文件系统活动。 在另一个终端，重新启动MySQL/MariaDB，例如: 重启mysql 或者: Brew服务重新启动mariadb 在终端上使用fs_usage，应该显示正确的位置，例如。 15:52:22 access /usr/local/Cellar/mariadb/10.1.14/my.cnf 0.000002 sh 因此，如果该文件不存在，就创建一个。

您可以打开一个终端并键入locate my.cnf

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

我在macOS Sierra上安装了MySql 5.7.12

支持文件位于

/usr/local/opt/mysql/support-files

只要将my-default.cnf复制到/etc/my.cnf或/etc/mysql/my.cnf，重新启动时配置就会被拾取。

在Mac OS X Maverick的情况下，当MySQL通过Homebrew安装时，它位于/usr/local/opt/mysql/my.cnf