Redis - Lists


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Redis Lists are simply lists of strings, sorted by insertion order. You can add elements in Redis lists in the head or the tail of the list.

Maximum length of a list is 232 - 1 elements (4294967295, more than 4 billion of elements per list).

Example

redis 127.0.0.1:6379> LPUSH tutorials redis 
(integer) 1 
redis 127.0.0.1:6379> LPUSH tutorials mongodb 
(integer) 2 
redis 127.0.0.1:6379> LPUSH tutorials mysql 
(integer) 3 
redis 127.0.0.1:6379> LRANGE tutorials 0 10  
1) "mysql" 
2) "mongodb" 
3) "redis"

In the above example, three values are inserted in Redis list named ‘tutorials’ by the command LPUSH.

Redis Lists Commands

Following table lists some basic commands related to lists.

S.No Command & Description
1 BLPOP key1 [key2 ] timeout

Removes and gets the first element in a list, or blocks until one is available

2 BRPOP key1 [key2 ] timeout

Removes and gets the last element in a list, or blocks until one is available

3 BRPOPLPUSH source destination timeout

Pops a value from a list, pushes it to another list and returns it; or blocks until one is available

4 LINDEX key index

Gets an element from a list by its index

5 LINSERT key BEFORE|AFTER pivot value

Inserts an element before or after another element in a list

6 LLEN key

Gets the length of a list

7 LPOP key

Removes and gets the first element in a list

8 LPUSH key value1 [value2]

Prepends one or multiple values to a list

9 LPUSHX key value

Prepends a value to a list, only if the list exists

10 LRANGE key start stop

Gets a range of elements from a list

11 LREM key count value

Removes elements from a list

12 LSET key index value

Sets the value of an element in a list by its index

13 LTRIM key start stop

Trims a list to the specified range

14 RPOP key

Removes and gets the last element in a list

15 RPOPLPUSH source destination

Removes the last element in a list, appends it to another list and returns it

16 RPUSH key value1 [value2]

Appends one or multiple values to a list

17 RPUSHX key value

Appends a value to a list, only if the list exists



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