prepend operation in Memcached is used to add some data at the beginning of an existing key's value. This can be useful in scenarios where you want to update logs, messaging systems, or any other data structure where updates need to be made in a prepend (add at the beginning) manner.
In this example, we first create a connection to the Memcached server. Then we set a key named 'key' with the value 'world'. Using the
prepend command, we then prepend the string 'Hello ' to our existing value. When we fetch the value of 'key', it returns 'Hello world'.
In this example, we try to prepend to a key that does not exist. Since the key must be pre-existing in Memcached for the prepend operation, this will throw an error.
setto ensure the existence of the key.
Can I prepend on a non-existent key in Memcached?
prepend function only works with existing keys. If you try to prepend to a non-existent key, it will result in an error.
How fast is the prepend operation in Memcached?
The prepend operation in Memcached is slower compared to normal set/get operations since it requires alteration of existing data.