redis lpush

In Redis, the LPUSH command is used to insert one or multiple values (elements) at the beginning of a list. Lists in Redis are implemented as a series of ordered values. When you use LPUSH, it pushes the specified values to the front (left) of the list.

The basic syntax of the LPUSH command is as follows:

css
LPUSH key value [value ...]

key: This is the name of the list where you want to push the values.value: One or more values that you want to insert at the beginning of the list.

Here's an example of how you might use the LPUSH command in the Redis command-line interface:

shell
LPUSH mylist "value1" "value2" "value3"

After executing this command, if mylist did not exist previously, it will be created as a list, and the values will be inserted at the left end of the list. The list will look like this:

arduino
1) "value3"
2) "value2"
3) "value1"

In this example, "value3" is at the front of the list, "value2" is next, and "value1" is at the end.

You can use LRANGE to retrieve elements from the list to inspect its contents or LLEN to get the length of the list.

shell
LRANGE mylist 0 -1

This would return all elements in the list, and you would see:

arduino
1) "value3"
2) "value2"
3) "value1"

Keep in mind that LPUSH and LRANGE are just two of the many list-related commands available in Redis for working with lists. Lists can be used for various purposes, such as implementing queues, stacks, or managing ordered data.

RPUSH：与LPUSH相反，RPUSH命令将一个或多个值添加到列表的末尾。这可用于构建另一种类型的列表。

shell
RPUSH mylist "value4" "value5" "value6"

这将在列表的右侧添加值，使列表变为：

arduino
1) "value3"
2) "value2"
3) "value1"
4) "value4"
5) "value5"
6) "value6"

LPOP：LPOP命令从列表的左侧移除并返回第一个元素，并将列表缩短一个元素。

shell
LPOP mylist

执行后，列表将变为：

arduino
1) "value2"
2) "value1"
3) "value4"
4) "value5"
5) "value6"

RPOP：RPOP命令从列表的右侧移除并返回最后一个元素，并将列表缩短一个元素。

shell
RPOP mylist

执行后，列表将变为：

arduino
1) "value2"
2) "value1"
3) "value4"
4) "value5"

LINDEX：LINDEX命令用于获取列表中指定位置的元素。

shell
LINDEX mylist 2

这将返回列表中索引为2的元素，即"value4"。