A single instance of MySQL can hold many separate databases. It is important to specify the database to which subsequent commands will be issued.
From within the mysql command (see Connect to a MySQL server using the mysql command for more information), the ‘use’ command selects the named database for use:
This command will select the database named ‘financial’ for use. Subsequent SQL commands will affect this database. The use command must be used on a separate line with no additional SQL commands.