Memcached delete command is used to delete an existing key from the Memcached server.
Syntax
The basic syntax of Memcached delete command is as shown below −
delete key [noreply]
Output
CAS command may produce one of the following result −
- DELETED indicates successful deletion.
- ERROR indicates error while deleting data or wrong syntax.
- NOT_FOUND indicates that the key does not exist in the Memcached server.
Example
In this example, we use tutorialspoint as a key and store memcached in it with an expiration time of 900 seconds. After this, it deletes the stored key.
set tutorialspoint 0 900 9 memcached STORED get tutorialspoint VALUE tutorialspoint 0 9 memcached END delete tutorialspoint DELETED get tutorialspoint END delete tutorialspoint NOT_FOUND
Delete Data Using Java Application
To delete data from a Memcached server, you need to use the Memcached delete method.
Example
import java.net.InetSocketAddress;
import java.util.concurrent.Future;
import net.spy.memcached.MemcachedClient;
public class MemcachedJava {
public static void main(String[] args) {
try{
// Connecting to Memcached server on localhost
MemcachedClient mcc = new MemcachedClient(new InetSocketAddress("127.0.0.1", 11211));
System.out.println("Connection to server sucessful.");
// add data to memcached server
Future fo = mcc.set("tutorialspoint", 900, "World's largest online tutorials library");
// print status of set method
System.out.println("set status:" + fo.get());
// retrieve and check the value from cache
System.out.println("tutorialspoint value in cache - " + mcc.get("tutorialspoint"));
// try to add data with existing key
Future fo = mcc.delete("tutorialspoint");
// print status of delete method
System.out.println("delete status:" + fo.get());
// retrieve and check the value from cache
System.out.println("tutorialspoint value in cache - " + mcc.get("codingground"));
// Shutdowns the memcached client
mcc.shutdown();
}catch(Exception ex)
System.out.println(ex.getMessage());
}
}
Output
On compiling and executing the program, you get to see the following output −
Connection to server successful set status:true tutorialspoint value in cache - World's largest online tutorials library delete status:true tutorialspoint value in cache - null