When any of the sorted sets contains elements, this command behaves exactly like ZMPOP.
When used inside a MULTI/EXEC block, this command behaves exactly like ZMPOP.
When all sorted sets are empty, Redis will block the connection until another client adds members to one of the keys or until the
timeout (a double value specifying the maximum number of seconds to block) elapses.
timeout of zero can be used to block indefinitely.
See ZMPOP for more information.
Array reply: specifically:
nilwhen no element could be popped.
- A two-element array with the first element being the name of the key from which elements were popped, and the second element is an array of the popped elements. Every entry in the elements array is also an array that contains the member and its score.