# mysqldump --add-drop-database option

--add-drop-database is a mysqldump option that is used to write a DROP DATABASE statement before each CREATE DATABASE statement. The option should be used in togheter with the option --all-databases or --databases because no CREATE DATABASE statements are written unelss on of the two options is specified.

# Togheter with --all-databases option
mysqldump --add-drop-database --all-databases > my_backup.sql
# Togheter with --databases option
mysqldump --add-drop-database --databases my_first_db my_second_db > my_backup.sql

If the option is used without --all-databases or --databases, DROP DATABASE statements will not be written because only those two options write CREATE DATABASE statements.

# DROP DATABASE statements will not be written
mysqldump --add-drop-database > my_backup.sql