In Redis, the LINDEX
command returns the element at the specified index at the specified key.
Tag: lists
Redis LLEN Command Explained
In Redis, the LLEN
command returns the length of the list stored at the specified key.
Redis LRANGE Command Explained
In Redis, the LRANGE
command returns the specified elements of the list stored at the specified key.
The command requires us to specify a start and stop position for the elements to return. These are zero based indexes, so 0
is the first element in the list.
We can specify -1
for the last element in the list.
Redis LMPOP Command Explained
In Redis, the LMPOP
command pops one or more elements from the first non-empty list key from the list of provided key names.
The LMPOP
command is similar to LPOP
, except that it can accept multiple keys. It’s also similar to BLPOP
(which accepts multiple keys), except that it can pop multiple elements (BLPOP
can only pop one element).
Redis BLMPOP Command Explained
In Redis, the BLMPOP
command is the blocking variant of LMPOP
.
Just like the LMPOP
command, BLMPOP
pops one or more elements from the first non-empty list key from the list of provided key names. However, unlike LMPOP
, if all lists are empty, BLMPOP
blocks the connection until another client pushes to it or until the timeout
(a double value specifying the maximum number of seconds to block) elapses.
Redis BRPOP Command Explained
In Redis, the BRPOP
command is the blocking variant of the RPOP
command. It blocks the connection when there are no elements to pop from any of the given lists.
The way the command works is that an element is popped from the tail of the first list that is non-empty, with the given keys being checked in the order that they are given. When there are no elements to pop from any of the lists, it blocks the connection.
Continue readingRedis RPOP Command Explained
In Redis, the RPOP
command removes and returns the last elements of the list stored at the specified key.
By default, the command pops a single element from the end of the list. However, we have the option of passing a second argument that specifies how many elements to pop.
Continue readingRedis BLPOP Command Explained
In Redis, the BLPOP
command is the blocking version of the LPOP
command. It blocks the connection when there are no elements to pop from any of the given lists.
The way the command works is that an element is popped from the head of the first list that is non-empty, with the given keys being checked in the order that they are given. When there are no elements to pop from any of the lists, it blocks the connection.
Continue readingRedis LPOP Command Explained
In Redis, the LPOP
command removes and returns the first elements of the list stored at the specified key.
By default, the command pops a single element from the beginning of the list. However, we have the option of passing a second argument that specifies how many elements to pop.
Continue readingRedis RPUSHX Command Explained
In Redis, the RPUSHX
command inserts one or more values into the tail of the list at the specified key, but only if the key exists and it contains a list.
If the key doesn’t exist, no operation is performed. If the key exists but it doesn’t contain a list, an error is returned.
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