Available since: 1.0.0
Time complexity: O(1)
Decrements the number stored at
key by one.
If the key does not exist, it is set to
0 before performing the operation.
An error is returned if the key contains a value of the wrong type or contains a
string that can not be represented as integer.
This operation is limited to 64 bit signed integers.
INCR for extra information on increment/decrement operations.
Integer reply: the value of
key after the decrement