Memcached 简明教程
Memcached - Delete Key
Memcached delete 命令用于从 Memcached 服务器中删除现有密钥。
Memcached delete command is used to delete an existing key from the Memcached server.
Syntax
Memcached delete 命令的基本语法如下所示：
The basic syntax of Memcached delete command is as shown below −
delete key [noreply]Output
CAS 命令可能生成以下结果之一：
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
在此示例中，我们使用 tutorialspoint 作为密钥，并将 memcached 存储在其中，其到期时间为 900 秒。此后，它将删除存储的密钥。
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_FOUNDDelete Data Using Java Application
若要从 Memcached 服务器删除数据，您需要使用 Memcached delete 方法。
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());
}
}