This is made from Android studio
I have a SQLite database for the questions for my quiz game.
It basically works: it has 20 questions for the user to answer correctly, but I want to switch things and I added a difficulty setting easy - 10 easy questions medium - 15 questions hard - 20 questions.
I just made another class for the medium and hard difficulties and just copied and pasted the codes and questions over from the original database class and just changed the questions.
It worked. However the questions are still the same (all 20 questions are still there). I even tried to remove all the questions in the array (when there should be no questions cause I removed them all) and the same 20 questions are there.
tldr: the same 20 questions are still showing up regardless if it is removed/added/edited from the array
private Context context;
private static final String DB_NAME = "TQuiz.db";
//If you want to add more questions or wanna update table values
//or any kind of modification in db just increment version no.
private static final int DB_VERSION = 3;
//Table name
private static final String TABLE_NAME = "TQ";
//Id of question
private static final String UID = "_UID";
//Question
private static final String QUESTION = "QUESTION";
//Option A
private static final String OPTA = "OPTA";
//Option B
private static final String OPTB = "OPTB";
//Option C
private static final String OPTC = "OPTC";
//Option D
private static final String OPTD = "OPTD";
//Answer
private static final String ANSWER = "ANSWER";
//So basically we are now creating table with first column-id , sec column-question , third column -option A, fourth column -option B , Fifth column -option C , sixth column -option D , seventh column - answer(i.e ans of question)
private static final String CREATE_TABLE = "CREATE TABLE " + TABLE_NAME + " ( " + UID + " INTEGER PRIMARY KEY AUTOINCREMENT , " + QUESTION + " VARCHAR(255), " + OPTA + " VARCHAR(255), " + OPTB + " VARCHAR(255), " + OPTC + " VARCHAR(255), " + OPTD + " VARCHAR(255), " + ANSWER + " VARCHAR(255));";
//Drop table query
private static final String DROP_TABLE = "DROP TABLE IF EXISTS " + TABLE_NAME;
TriviaQuizHelper(Context context) {
super(context, DB_NAME, null, DB_VERSION);
this.context = context;
}
@Override
public void onCreate(SQLiteDatabase sqLiteDatabase) {
//OnCreate is called only once
sqLiteDatabase.execSQL(CREATE_TABLE);
}
@Override
public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {
//OnUpgrade is called when ever we upgrade or increment our database version no
sqLiteDatabase.execSQL(DROP_TABLE);
onCreate(sqLiteDatabase);
}
void allQuestion() {
ArrayList<TriviaQuestion> arraylist = new ArrayList<>();
arraylist.add(new TriviaQuestion("Galileo was an Italian astronomer who developed?" , "Telescope", "Airoplane", "Electricity", "Train", "Telescope"));
arraylist.add(new TriviaQuestion("Who is the father of Geometry ?" , "Aristotle", "Euclid", "Pythagoras", "Kepler", "Euclid"));
arraylist.add(new TriviaQuestion("Who was known as Iron man of India ?", "Govind Ballabh Pant", "Jawaharlal Nehru", "Subhash Chandra Bose", "Sardar Vallabhbhai Patel", "Sardar Vallabhbhai Patel"));
arraylist.add(new TriviaQuestion("The first woman in space was ?", "Valentina Tereshkova", "Sally Ride", "Naidia Comenci", "Tamara Press", "Valentina Tereshkova"));
arraylist.add(new TriviaQuestion("Who is the Flying Sikh of India ?", "Mohinder Singh", "Joginder Singh", "Ajit Pal Singh", "Milkha singh", "Milkha singh"));
arraylist.add(new TriviaQuestion("The Indian to beat the computers in mathematical wizardry is", "Ramanujam", "Rina Panigrahi", "Raja Ramanna", "Shakunthala Devi", "Shakunthala Devi"));
arraylist.add(new TriviaQuestion("Who is Larry Pressler ?", "Politician", "Painter", "Actor", "Tennis player", "Politician"));
arraylist.add(new TriviaQuestion("Michael Jackson is a distinguished person in the field of ?", "Pop Music", "Jounalism", "Sports", "Acting", "Pop Music"));
arraylist.add(new TriviaQuestion("The first Indian to swim across English channel was ?", "V. Merchant", "P. K. Banerji", "Mihir Sen", "Arati Saha", "Mihir Sen"));
arraylist.add(new TriviaQuestion("Who was the first Indian to make a movie?", "Dhundiraj Govind Phalke", " Asha Bhonsle", " Ardeshir Irani", "V. Shantaram", "Dhundiraj Govind Phalke"));
arraylist.add(new TriviaQuestion("Who is known as the ' Saint of the gutters ?", "B.R.Ambedkar", "Mother Teresa", "Mahatma Gandhi", "Baba Amte", "Mother Teresa"));
arraylist.add(new TriviaQuestion("Who invented the famous formula E=mc^2", "Albert Einstein", "Galilio", "Sarvesh", "Bill Gates", "Albert Einstein"));
arraylist.add(new TriviaQuestion("Who is elected as president of us 2016", "Donald Trump", "Hilary Clinton", "Jhon pol", "Barack Obama", "Donald Trump"));
arraylist.add(new TriviaQuestion("Who was the founder of company Microsoft", "Bill Gates", "Bill Clinton", "Jhon rio", "Steve jobs", "Bill Gates"));
arraylist.add(new TriviaQuestion("Who was the founder of company Apple ?", "Steve Jobs", "Steve Washinton", "Bill Gates", "Jobs Wills", "Steve Jobs"));
arraylist.add(new TriviaQuestion("Who was the founder of company Google ?", "Steve Jobs", "Bill Gates", "Larry Page", "Sundar Pichai", "Larry Page"));
arraylist.add(new TriviaQuestion("Who is know as god of cricket ?", "Sachin Tendulkar", "Kapil Dev", "Virat Koli", "Dhoni", "Sachin Tendulkar"));
arraylist.add(new TriviaQuestion("who has won ballon d'or of 2015 ?", "Lionel Messi", "Cristiano Ronaldo", "Neymar", "Kaka", "Lionel Messi"));
arraylist.add(new TriviaQuestion("who has won ballon d'or of 2014 ?", "Neymar", "Lionel Messi", "Cristiano Ronaldo", "Kaka", "Cristiano Ronaldo"));
arraylist.add(new TriviaQuestion("the Founder of the most famous gaming platform steam is ?",
"Bill Cliton", "Bill Williams", "Gabe Newell", "Bill Gates", "Gabe Newell"));
this.addAllQuestions(arraylist);
}
private void addAllQuestions(ArrayList<TriviaQuestion> allQuestions) {
SQLiteDatabase db = this.getWritableDatabase();
db.beginTransaction();
try {
ContentValues values = new ContentValues();
for (TriviaQuestion question : allQuestions) {
values.put(QUESTION, question.getQuestion());
values.put(OPTA, question.getOptA());
values.put(OPTB, question.getOptB());
values.put(OPTC, question.getOptC());
values.put(OPTD, question.getOptD());
values.put(ANSWER, question.getAnswer());
db.insert(TABLE_NAME, null, values);
}
db.setTransactionSuccessful();
} finally {
db.endTransaction();
db.close();
}
}
List<TriviaQuestion> getAllOfTheQuestions() {
List<TriviaQuestion> questionsList = new ArrayList<>();
SQLiteDatabase db = this.getWritableDatabase();
db.beginTransaction();
String column[] = {UID, QUESTION, OPTA, OPTB, OPTC, OPTD, ANSWER};
Cursor cursor = db.query(TABLE_NAME, column, null, null, null, null, null);
while (cursor.moveToNext()) {
TriviaQuestion question = new TriviaQuestion();
question.setId(cursor.getInt(0));
question.setQuestion(cursor.getString(1));
question.setOptA(cursor.getString(2));
question.setOptB(cursor.getString(3));
question.setOptC(cursor.getString(4));
question.setOptD(cursor.getString(5));
question.setAnswer(cursor.getString(6));
questionsList.add(question);
}
db.setTransactionSuccessful();
db.endTransaction();
cursor.close();
db.close();
return questionsList;
}}
If you copied you database class, but forget to change table name - it can lead to duplication of data.