memcached flush_all command is used to delete all data (key-value pairs) from the memcached server. it accepts an optional parameter called time that sets a time after which the memcached data is to be cleared.

syntax

the basic syntax of memcached flush_all command is as shown below −

flush_all [time] [noreply]

the above command always returns ok.

example

in the following example, we store some data into the memcached server and then clear all the data.

set tutorialspoint 0 900 9
memcached
stored
get tutorialspoint
value tutorialspoint 0 9
memcached
end
flush_all
ok
get tutorialspoint
end

clear data using java application

to clear data from a memcached server, you need to use the memcached flush method.

example

import net.spy.memcached.memcachedclient;
public class memcachedjava {
   public static void main(string[] args) {
     
     // connecting to memcached server on localhost
      memcachedclient mcc = new memcachedclient(new
      inetsocketaddress("127.0.0.1", 11211));
      system.out.println("connection to server sucessfully");
      system.out.println("set status:"+mcc.set("count", 900, "5").isdone());
      
      // get value from cache
      system.out.println("get from cache:"+mcc.get("count"));
     
      // now increase the stored value
      system.out.println("increment value:"+mcc.incr("count", 2));
     
      // now decrease the stored value
      system.out.println("decrement value:"+mcc.decr("count", 1));
      
      // now get the final stored value
      system.out.println("get from cache:"+mcc.get("count"));
      
      // now clear all this data
      system.out.println("clear data:"+mcc.flush().isdone());
   }
}

output

on compiling and executing the program, you get to see the following output −

connection to server successfully
set status:true
get from cache:5
increment value:7
decrement value:6
get from cache:6
clear data:true