EXISTS
Syntax
EXISTS key [key ...]
Time complexity: O(N) where N is the number of keys to check.
Returns if key
exists.
The user should be aware that if the same existing key is mentioned in the arguments multiple times, it will be counted multiple times. So if somekey
exists, EXISTS somekey somekey
will return 2.
Return
Integer reply, specifically the number of keys that exist from those specified as arguments.
Examples
dragonfly> SET key1 "Hello"
"OK"
dragonfly> EXISTS key1
(integer) 1
dragonfly> EXISTS nosuchkey
(integer) 0
dragonfly> SET key2 "World"
"OK"
dragonfly> EXISTS key1 key2 nosuchkey
(integer) 2