MGET
Syntax
1. MGET key [key ...]
Time complexity: O(N) where N is the number of keys to retrieve.
Returns the values of all specified keys. For every key that does not hold a string value or does not exist, the special value nil is returned. Because of this, the operation never fails.
Return
Array reply: list of values at the specified keys.
Examples
1. dragonfly> SET key1 "Hello"
2. "OK"
3. dragonfly> SET key2 "World"
4. "OK"
5. dragonfly> MGET key1 key2 nonexisting
6. 1) "Hello"
7. 2) "World"
8. 3) (nil)
