LINSERT
Syntax
LINSERT key <BEFORE | AFTER> pivot element
- Available since:
- 2.2.0
- Time complexity:
- O(N) where N is the number of elements to traverse before seeing the value pivot. This means that inserting somewhere on the left end on the list (head) can be considered O(1) and inserting somewhere on the right end (tail) is O(N).
- ACL categories:
-
@write
,@list
,@slow
,
Inserts element
in the list stored at key
either before or after the reference
value pivot
.
When key
does not exist, it is considered an empty list and no operation is
performed.
An error is returned when key
exists but does not hold a list value.
Examples
RESP2/RESP3 Reply
One of the following:
- Integer reply: the list length after a successful insert operation.
- Integer reply:
0
when the key doesn't exist. - Integer reply:
-1
when the pivot wasn't found.