Decrements the integer value of a key by one. Uses 0 as initial value if the key doesn’t exist.
DECR
key
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.
See INCR
for extra information on increment/decrement
operations.
Integer reply: the value of the key after decrementing it.
O(1)
@fast @string @write
127.0.0.1:6379> SET mykey "10"
OK
127.0.0.1:6379> DECR mykey
(integer) 9
127.0.0.1:6379> SET mykey "234293482390480948029348230948"
OK
127.0.0.1:6379> DECR mykey
(error) ERR value is not an integer or out of range
APPEND, DECRBY, GET, GETDEL, GETEX, GETRANGE, INCR, INCRBY, INCRBYFLOAT, LCS, MGET, MSET, MSETNX, SET, SETRANGE, STRLEN.