RPUSHX key element [element …]
Time complexity: O(1) for each element added, so O(N) to add N elements when the command is called with multiple arguments.
Inserts specified values at the tail of the list stored at , only if already exists and holds a list. In contrary to , no operation will be performed when does not yet exist.
redis> RPUSH mylist "Hello"
redis> RPUSHX mylist "World"
redis> LRANGE mylist 0 -1
redis> LRANGE myotherlist 0 -1
redis>