lpush key value
- 作用: 把值插入到鏈接頭部
rpop key
- 作用: 返回並刪除鏈表尾元素
rpush,lpop: 不解釋
lrange key start stop
- 作用: 返回鏈表中[start ,stop]中的元素
- 規律: 左數從0開始,右數從-1開始
代碼練習
127.0.0.1:6379> lpush character a
(integer) 1
127.0.0.1:6379> rpush character b
(integer) 2
127.0.0.1:6379> rpush character c
(integer) 3
127.0.0.1:6379> lpush character 0
(integer) 4
127.0.0.1:6379> lrange character 1 2
1) "a"
2) "b"
127.0.0.1:6379> lrange character 1 3
1) "a"
2) "b"
3) "c"
127.0.0.1:6379> lrange character 0 3
1) "0"
2) "a"
3) "b"
4) "c"
127.0.0.1:6379> lrange character 0 -1
1) "0"
2) "a"
3) "b"
4) "c"
127.0.0.1:6379> lpop character
"0"
127.0.0.1:6379> lrange character 0 -1
1) "a"
2) "b"
3) "c"
127.0.0.1:6379> rpop character
"c"
127.0.0.1:6379> lrange character 0 -1
1) "a"
2) "b"
lrem key count value
- 作用: 從key鏈表中刪除 value值
- 注: 刪除count的絕對值個value後結束
- Count>0 從表頭刪除
- Count<0 從表尾刪除
127.0.0.1:6379> lpush answer a b c a b d a
(integer) 7
127.0.0.1:6379> lrange answer 0 -1
1) "a"
2) "d"
3) "b"
4) "a"
5) "c"
6) "b"
7) "a"
127.0.0.1:6379> lrem answer 1 b
(integer) 1
127.0.0.1:6379> lrange answer 0 -1
1) "a"
2) "d"
3) "a"
4) "c"
5) "b"
6) "a"
127.0.0.1:6379> lrem answer -2 a
(integer) 2
127.0.0.1:6379> lrange answer 0 -1
1) "a"
2) "d"
3) "c"
4) "b"
ltrim key start stop
- 作用: 剪切key對應的鏈接,切[start,stop]一段,並把該段重新賦給key
127.0.0.1:6379> rpush character a b c d e f
(integer) 6
127.0.0.1:6379> lrange character 0 -1
1) "a"
2) "b"
3) "c"
4) "d"
5) "e"
6) "f"
127.0.0.1:6379> ltrim character 2 5
OK
127.0.0.1:6379> lrange character 0 -1
1) "c"
2) "d"
3) "e"
4) "f"
lindex key index
- 作用: 返回index索引上的值,
- 如 lindex key 2
llen key
- 作用:計算鏈接表的元素個數
redis 127.0.0.1:6379> llen task
(integer) 3
linsert key after|before search value
- 作用: 在key鏈表中尋找’search’,並在search值之前|之後,.插入value
- 注: 一旦找到一個search後,命令就結束了,因此不會插入多個value
rpoplpush source dest
-
作用: 把source的尾部拿出,放在dest的頭部,並返回 該單元值
-
場景: task + bak 雙鏈表完成安全隊列
- Task列表
---------- | | | | ----------
- bak列表
---------- | | | | ----------
- 業務邏輯:
- 1:Rpoplpush task bak
- 2:接收返回值,並做業務處理
- 3:如果成功,rpop bak 清除任務. 如不成功,下次從bak表裏取任務
brpop ,blpop key timeout
- 作用:等待彈出key的尾/頭元素,
- Timeout爲等待超時時間
- 如果timeout爲0,則一直等待
- 場景: 長輪詢Ajax,在線聊天時,能夠用到
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