title: Random data in SQLite
body: <p>I am asking your help to fix my problem in my android applications. I have a project to make a quiz apps, and I want to implement linear congruential method in this game. I have success to random my data, but I still have no idea how to implement the method. Here is my code; </p>
  
  <pre><code>public class QuizHelper extends SQLiteOpenHelper {
      private static final int DATABASE_VERSION = 1;
      // Database Name
      private static final String DATABASE_NAME = "mathsone";
      // tasks table name
      private static final String TABLE_QUEST = "quest";
      // tasks Table Columns names
      private static final String KEY_ID = "qid";
      private static final String KEY_QUES = "question";
      private static final String KEY_ANSWER = "answer"; // correct option
      private static final String KEY_OPTA = "opta"; // option a
      private static final String KEY_OPTB = "optb"; // option b
      private static final String KEY_OPTC = "optc" ; // option c
      private static final String KEY_OPTD = "optd" ;
  
      private SQLiteDatabase dbase;
  
      public QuizHelper(Context context) {
          super(context, DATABASE_NAME, null, DATABASE_VERSION);
      }
  
      @Override
      public void onCreate(SQLiteDatabase db) {
          dbase = db;
          String sql = "CREATE TABLE IF NOT EXISTS " + TABLE_QUEST + " ( "
                  + KEY_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + KEY_QUES
                  + " TEXT, " + KEY_ANSWER + " TEXT, " + KEY_OPTA + " TEXT, "
                  + KEY_OPTB + " TEXT, " + KEY_OPTC + " TEXT, "+ KEY_OPTD + " TEXT)";
          db.execSQL(sql);
          addQuestion();
          // db.close();
  
      }
  
      private void addQuestion() {
          Question q1 = new Question("5+2 = ?", "7", "8", "6", "4", "7");
          this.addQuestion(q1);
          Question q2 = new Question("2+18 = ?", "18", "19", "20", "4", "20");
          this.addQuestion(q2);
          Question q3 = new Question("10-3 = ?", "6", "7", "8", "5", "7");
          this.addQuestion(q3);
          Question q4 = new Question("5+7 = ?", "12", "13", "14", "5", "12");
          this.addQuestion(q4);
          Question q5 = new Question("3-1 = ?", "1", "3", "2", "5", "2");
          this.addQuestion(q5);
          Question q6 = new Question("0+1 = ?", "1", "0", "10", "5", "1");
          this.addQuestion(q6);
          Question q7 = new Question("9-9 = ?", "0", "9", "1", "5", "0");
          this.addQuestion(q7);
          Question q8 = new Question("3+6 = ?", "8", "7", "9", "5", "9");
          this.addQuestion(q8);
          Question q9 = new Question("1+5 = ?", "6", "7", "5", "5", "6");
          this.addQuestion(q9);
          Question q10 = new Question("7-5 = ?", "3", "2", "6", "5", "2");
          this.addQuestion(q10);
  
          // END
      }
  
      @Override
      public void onUpgrade(SQLiteDatabase db, int oldV, int newV) {
          // Drop older table if existed
          db.execSQL("DROP TABLE IF EXISTS " + TABLE_QUEST);
  
          // Create tables again
          onCreate(db);
      }
  
      // Adding new question
      public void addQuestion(Question quest) {
          // SQLiteDatabase db = this.getWritableDatabase();
          ContentValues values = new ContentValues();
          values.put(KEY_QUES, quest.getQUESTION());
          values.put(KEY_ANSWER, quest.getANSWER());
          values.put(KEY_OPTA, quest.getOPTA());
          values.put(KEY_OPTB, quest.getOPTB());
          values.put(KEY_OPTC, quest.getOPTC());
          values.put(KEY_OPTD, quest.getOPTD());
  
          // Inserting Row
          dbase.insert(TABLE_QUEST, null, values);
      }
  
      public List&lt;Question&gt; getAllQuestions() {
          List&lt;Question&gt; quesList = new ArrayList&lt;Question&gt;();
          // Select All Query
          String selectQuery = "SELECT  * FROM " + TABLE_QUEST  + " ORDER BY RANDOM(), null";
          dbase = this.getReadableDatabase();
          Cursor cursor = dbase.rawQuery(selectQuery, null);
          // looping through all rows and adding to list
          if (cursor.moveToFirst()) {
              do {
                  Question quest = new Question();
                  quest.setID(cursor.getInt(0));
                  quest.setQUESTION(cursor.getString(1));
                  quest.setANSWER(cursor.getString(2));
                  quest.setOPTA(cursor.getString(3));
                  quest.setOPTB(cursor.getString(4));
                  quest.setOPTC(cursor.getString(5));
                  quest.setOPTD(cursor.getString(6));
  
                  quesList.add(quest);
              } while (cursor.moveToNext());
          }
          // return quest list
          return quesList;
      }
  
  }
  </code></pre>
  
  <p>you can find the formula here </p>
  
  <p><a href="https://id.wikipedia.org/wiki/Metode_linear_kongruen" rel="nofollow noreferrer">https://id.wikipedia.org/wiki/Metode_linear_kongruen</a></p>