# To dump a database to a file (Note that your password will appear in your command history!):
mysqldump -uusername -ppassword the-database > db.sql

# To dump a database to a file:
mysqldump -uusername -p the-database > db.sql

 # To dump a database to a .tgz file (Note that your password will appear in your command history!):
mysqldump -uusername -ppassword the-database | gzip -9 > db.sql

# To dump a database to a .tgz file:
mysqldump -uusername -p the-database | gzip -9 > db.sql

 # To dump all databases to a file (Note that your password will appear in your command history!):
mysqldump -uusername -ppassword --all-databases > all-databases.sql

# To dump all databases to a file:
mysqldump -uusername -p --all-databases > all-databases.sql

# To export the database structure only:
mysqldump --no-data -uusername -p the-database > dump_file

# To export the database data only:
mysqldump --no-create-info -uusername -p the-database > dump_file