Store data in a Text File in Android Studio

I HAVE TWO QUESTIONS:

1. I have a text file containing words and its equivalent score. This is how it looks like:

word_equivscore melody_3

I use text file to store a bunch of words and its corresponding score. It goes this way:

word on textview > click button to search the word > if the word is on the database/text file, add word in Listview > Else, clear textview.

Codes I am currently using:

public long insertData(String Word, int Score)
    {
        SQLiteDatabase db =  helper.getWritableDatabase();
        ContentValues contentValues=new ContentValues();
        contentValues.put(DBHelper.WORD, Word);
        contentValues.put(DBHelper.SCORE, Score);
        long id=db.insert(DBHelper.TABLE_NAME, null, contentValues);
        return id;
    }

public String getData(String word)
    {
        SQLiteDatabase db = helper.getWritableDatabase();
        String[] columns={DBHelper.WORD, DBHelper.SCORE};
        Cursor cursor=db.query(DBHelper.TABLE_NAME, columns, DBHelper.WORD+ "= '"+word+"'", null, null, null, null);
        StringBuffer buffer = new StringBuffer();
        while(cursor.moveToNext())
        {
            int index1 =cursor.getColumnIndex(DBHelper.WORD);
            int index2 =cursor.getColumnIndex(DBHelper.SCORE);
            String words =cursor.getString(index1);
            String score =cursor.getString(index2);
            buffer.append(score +"\n");
        }
        return buffer.toString();
    }

    static class DBHelper extends SQLiteOpenHelper
    {
        private static final String DATABASE_NAME= "BoggleIT";
        private static final String TABLE_NAME ="dbtable";
        private static final String UID ="_id";
        private static final String WORD ="word";
        private static final String SCORE ="score";
        private static final int DATABASE_VERSION=4;
        private static final String CREATE_TABLE="CREATE TABLE "+TABLE_NAME +" ("+UID+" INTEGER PRIMARY KEY AUTOINCREMENT, "+WORD+" VARCHAR(255), "+SCORE+" VARCHAR(255));";
        private static final String DROP_TABLE="DROP TABLE IF EXISTS "+TABLE_NAME;
        private Context context;

        DBHelper(Context context) {
            // TODO Auto-generated constructor stub
            super (context, DATABASE_NAME, null, DATABASE_VERSION);
            this.context = context;
            //Message.message(context, "constructor called");
        }


//onCreate here

2. How to restrict duplicate entry in listview? See my codes.

ArrayAdapter<String> adapter;
    ArrayList<String> myList;

//onCreate
myList = new ArrayList<String>();
        adapter = new ArrayAdapter<String>(getApplicationContext(), android.R.layout.simple_list_item_1, myList);
        wordList.setAdapter(adapter);

//end of onCreate

String s1, s2, newData;

    public void viewWord(View view) {
        s1 = search.getText().toString();
        s2 = dbHelper.getData(s1);
        newData = text.getText().toString();

        s1.trim();
        s2.trim();
        generatedString.trim();


        //score if in database

        calculate();

        adapter = (ArrayAdapter) wordList.getAdapter();
        adapter.add((String)newData);

I am using Android Studio and SQLite for my db.

P.S. I don't have any idea on these two.