FLUSHDB [ASYNC | SYNC] Available since: 1.0.0 Time complexity: O(N) where N is the number of keys in the selected database ACL categories: @keyspace, @write, @slow, @dangerous, Delete all the keys of the currently selected DB. This command never fails. By default, FLUSHDB will synchronously flush all keys from the database. Starting with Redis 6.2, setting the lazyfree-lazy-user-flush configuratio