Delete all keys across databases

To delete all keys across redis databases, just enter FLUSHALL.

docker exec -it redis redis-cli

127.0.0.1:6379[1]> SELECT 1
OK
127.0.0.1:6379[1]> KEYS *
1) "key1"
127.0.0.1:6379[1]> SELECT 2
OK
127.0.0.1:6379[2]> KEYS *
1) "key2"
127.0.0.1:6379[2]> FLUSHALL
OK
127.0.0.1:6379[2]> SELECT 1
OK
127.0.0.1:6379[1]> KEYS *
(empty array)
127.0.0.1:6379[1]> SELECT 2
OK
127.0.0.1:6379[2]> KEYS *
(empty array)