How to use delete all keys in a Redis
In Redis, you can flush the cache/database and delete all keys from all databases or from the particular database only using flushall and flushdb commands.
To delete all keys from all Redis databases use the flushall command.
Delete all keys in Redis
Delete all keys from all redis databases:
redis-cli flushall
Delete all keys of the currently selected Redis database:
redis-cli FLUSHDB
Delete all keys of the specified Redis database:
redis-cli -n <database_number> FLUSHDB