


What\'s the Difference Between Hyphens (-) and Underscores (_) in MySQL Configuration Files?
Understanding MySQL Configuration File Sections
The MySQL configuration file, typically named my.ini or my.cnf, is essential for configuring various aspects of the database server and its interactions with clients. It consists of multiple sections, each governing specific parameters and settings.
Section Descriptions:
- [mysql]: Configuration directives for the MySQL command line client (mysql) and other client-related options.
- [client]: Global settings that affect all connecting clients, including the MySQL command line client.
- [mysqld]: Parameters that apply to the MySQL server, controlling its operation and behavior.
- [mysqldump]: Specific settings for the mysqldump utility, used for exporting database data.
Special Characters: Hyphen (-) vs. Underscore (_)
In MySQL configuration files, a subtle but crucial distinction exists between the hyphen (-) and underscore (_). Hyphens are primarily used in command line parameters (e.g., --verbose), while underscores are employed in options file parameters (e.g., init_connect).
The init_connect option in the [mysqld] section is a parameter that specifies SQL commands to be executed whenever a client establishes a new connection to the MySQL server. On the other hand, init-connect is a command line parameter that runs the specified SQL statement during startup but not for every client connection.
For further details on MySQL configuration files and options, refer to the official documentation: http://dev.mysql.com/doc/refman/5.5/en/option-files.html
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