Memcached prepend command

Memcached prepend command is used to append data in front of value(data value) that already exists key(key).

Syntax:

The basic syntax format of the prepend command is as follows:

prepend key flags exptime bytes [noreply]
value

The parameter description is as follows:

• key: The key in the key-value structure is used to find cached values.

• flags: Integer parameter that can include key-value pairs and is used by the client to store additional information about the key-value pairs .

• exptime: The length of time to keep key-value pairs in the cache (in seconds, 0 means forever)

• bytes: The number of bytes stored in the cache

• noreply (optional) : This parameter tells the server that no data needs to be returned

• value: The stored value (always located in the second line) (can be directly understood as the value in the key-value structure)

Example

The example is as follows:

• First we store a key php in Memcached, and its value is memcached.

• We then retrieve the value using the get command.

• Then, we use the prepend command to append "redis" after the value with the key php.

• Finally, we use the get command to retrieve the value.

set php 0 900 9
memcached
STORED
get php
VALUE php 0 14
memcached
END
prepend php 0 900 5
redis
STORED
get php
VALUE php 0 14
redismemcached
END

Output

If the data is added successfully, output:

STORED

Output information description:

• STORED: Output after successful saving.

• NOT_STORED: The key does not exist on Memcached.

• CLIENT_ERROR: Execution error.