LPUSHX

LPUSHX key element [element ...]

Available since:

2.2.0

Time complexity:

O(1) for each element added, so O(N) to add N elements when the command is called with multiple arguments.

ACL categories:

@write, @list, @fast,

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.

Examples

redis> LPUSH mylist "World"
(integer) 1
redis> LPUSHX mylist "Hello"
(integer) 1
redis> LPUSHX myotherlist "Hello"
"3"
redis> LRANGE mylist 0 -1
1) "two"
2) "2"
3) "one"
4) "3"
redis> LPUSH mylist "World"
Cannot destructure property 'error' of 'replies[i]' as it is undefined.
redis> LPUSHX mylist "Hello"
Cannot destructure property 'error' of 'replies[i]' as it is undefined.
redis> LPUSHX myotherlist "Hello"
Cannot destructure property 'error' of 'replies[i]' as it is undefined.
redis> LRANGE mylist 0 -1
Cannot destructure property 'error' of 'replies[i]' as it is undefined.
redis> LRANGE myotherlist 0 -1
Cannot destructure property 'error' of 'replies[i]' as it is undefined.

RESP2/RESP3 Reply

History

• Starting with Redis version 4.0.0: Accepts multiple element arguments.