6、ltrim
保留指定key 的值范围内的数据:
redis 127.0.0.1:6379> rpush mylist8 "one"
(integer) 1
redis 127.0.0.1:6379> rpush mylist8 "two"
(integer) 2
redis 127.0.0.1:6379> rpush mylist8 "three"
(integer) 3
redis 127.0.0.1:6379> rpush mylist8 "four"
(integer) 4
redis 127.0.0.1:6379> ltrim mylist8 1 -1
OK
redis 127.0.0.1:6379> lrange mylist8 0 -1
1) "two"
2) "three"
3) "four"
redis 127.0.0.1:6379>
(integer) 1
redis 127.0.0.1:6379> rpush mylist8 "two"
(integer) 2
redis 127.0.0.1:6379> rpush mylist8 "three"
(integer) 3
redis 127.0.0.1:6379> rpush mylist8 "four"
(integer) 4
redis 127.0.0.1:6379> ltrim mylist8 1 -1
OK
redis 127.0.0.1:6379> lrange mylist8 0 -1
1) "two"
2) "three"
3) "four"
redis 127.0.0.1:6379>
7、lpop
从list的头部删除元素,并返回删除元素:
redis 127.0.0.1:6379> lrange mylist 0 -1
1) "hello"
2) "world"
redis 127.0.0.1:6379> lpop mylist
"hello"
redis 127.0.0.1:6379> lrange mylist 0 -1
1) "world"
redis 127.0.0.1:6379>
1) "hello"
2) "world"
redis 127.0.0.1:6379> lpop mylist
"hello"
redis 127.0.0.1:6379> lrange mylist 0 -1
1) "world"
redis 127.0.0.1:6379>
8、rpop
从list的尾部删除元素,并返回删除元素:
redis 127.0.0.1:6379> lrange mylist2 0 -1
1) "hello"
2) "world"
redis 127.0.0.1:6379> rpop mylist2
"world"
redis 127.0.0.1:6379> lrange mylist2 0 -1
1) "hello"
redis 127.0.0.1:6379>
1) "hello"
2) "world"
redis 127.0.0.1:6379> rpop mylist2
"world"
redis 127.0.0.1:6379> lrange mylist2 0 -1
1) "hello"
redis 127.0.0.1:6379>
9、rpoplpush
从第一个list的尾部移除元素并添加到第二个list的头部,最后返回被移除的元素值,整个操作是原子的.如果第一个list是空或者不存在返回nil:
redis 127.0.0.1:6379> lrange mylist5 0 -1
1) "three"
2) "foo"
3) "hello"
redis 127.0.0.1:6379> lrange mylist6 0 -1
1) "hello"
2) "foo"
redis 127.0.0.1:6379> rpoplpush mylist5 mylist6
"hello"
redis 127.0.0.1:6379> lrange mylist5 0 -1
1) "three"
2) "foo"
redis 127.0.0.1:6379> lrange mylist6 0 -1
1) "hello"
2) "hello"
3) "foo"
redis 127.0.0.1:6379>
1) "three"
2) "foo"
3) "hello"
redis 127.0.0.1:6379> lrange mylist6 0 -1
1) "hello"
2) "foo"
redis 127.0.0.1:6379> rpoplpush mylist5 mylist6
"hello"
redis 127.0.0.1:6379> lrange mylist5 0 -1
1) "three"
2) "foo"
redis 127.0.0.1:6379> lrange mylist6 0 -1
1) "hello"
2) "hello"
3) "foo"
redis 127.0.0.1:6379>
10、lindex
返回名称为key的list中index位置的元素:
redis 127.0.0.1:6379> lrange mylist5 0 -1
1) "three"
2) "foo"
redis 127.0.0.1:6379> lindex mylist5 0
"three"
redis 127.0.0.1:6379> lindex mylist5 1
"foo"
redis 127.0.0.1:6379>
1) "three"
2) "foo"
redis 127.0.0.1:6379> lindex mylist5 0
"three"
redis 127.0.0.1:6379> lindex mylist5 1
"foo"
redis 127.0.0.1:6379>
11、llen
返回key对应list的长度:
redis 127.0.0.1:6379> llen mylist5
(integer) 2
redis 127.0.0.1:6379>
(integer) 2
redis 127.0.0.1:6379>