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.
Return
Integer reply: the list length after a successful insert operation, 0 if the key doesn't exist, and -1 when the pivot wasn't found.