Specifying Program Options
Most MySQL programs understand several options that affect how the program operates. Options may be specified on the command line or in option files. In addition, some options may be specified by setting environment variables. Options specified on the command line take precedence over options specified any other way, and options in option files take precedence over environment variable values.
Getting Online Help from MySQL Programs
Each MySQL program except mysqlbug, mysql.server, and safe_mysqld understands the --help option. This option provides a quick way to get online help about a program from the program itself. For example, if you're not sure how to use mysqlimport, invoke it like this for instructions: