How to implement an intentService in my android app

please i am building an app which receives notifications and inserts into a database, using parsepushbroadcastreceivers.

Below is my BackgroundActivity

public class BackgroundActivity extends ParsePushBroadcastReceiver {

    protected void onPushReceive(Context context, Intent intent) {

        String message="";

         SQLiteDatabase db;

            db = context.openOrCreateDatabase(
                "notification.db"
                , SQLiteDatabase.CREATE_IF_NECESSARY
                , null
                );
            //CREATE TABLES AND INSERT MESSAGES INTO THE TABLES
            String CREATE_TABLE_NOTICES = "CREATE TABLE IF NOT EXISTS notices ("
                    + "ID INTEGER primary key AUTOINCREMENT,"
                    + "NOTIFICATIONS TEXT)";
            db.execSQL(CREATE_TABLE_NOTICES);

       Bundle extras = intent.getExtras();

       if(extras !=null){
       String jsonData = extras.getString("com.parse.Data");
           try {   
               JSONObject notification = new JSONObject(jsonData);
               message = notification.getString("alert");


               String sql =
                    "INSERT or replace INTO notices (NOTIFICATIONS) "
                    + "VALUES('" + message + "')";       
                db.execSQL(sql);




        } catch (JSONException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } 
       }
    }
}

Upon advices from the books I read, i learnt it is better to use intentService to deal with the database( sqllite Database). Please I have been reading on the intent Service in my app but to no avail. I would be very much grateful if someone could kindly direct me as to how to implement intentService in the android app. Thanks