LPUSHX key element [element ...]

Inserts specified values at the head of the list stored at key, only if key already exists and holds a list. In contrary to LPUSH, no operation will be performed when key does not yet exist.

*返回值

整数: the length of the list after the push operation.

*历史

  • >= 4.0: Accepts multiple element arguments. In Redis versions older than 4.0 it was possible to push a single value per command.

*例子

redis>  LPUSH mylist "World"
(integer) 1
redis>  LPUSHX mylist "Hello"
(integer) 2
redis>  LPUSHX myotherlist "Hello"
(integer) 0
redis>  LRANGE mylist 0 -1
1) "Hello"
2) "World"
redis>  LRANGE myotherlist 0 -1
(empty list or set)
redis>