Get all members in Sorted Set
Solution 1:
You're in luck, as zrange does not take scores, but indices. 0 is the first index, and -1 will be interpreted as the last index:
zrange key 0 -1
To get a range by score, you would call zrangebyscore instead -- where -inf and +inf can be used to denote negative and positive infinity, respectively, as Didier Spezia notes in his comment:
zrangebyscore key -inf +inf