Sqlite DatabaseHelper. make a return method

Question

How do I make a method in my databaseHelper (that extends from SQLiteOpenHelper) class that returns a string for some data of a user.

For example

public String getUserPassword (String username){

    ..
    return password;
}

I just don't know how to make a Cursor that Search for the username (which is the primary key) and find the same user then return his password.

Answer 1

You can use the method rawQuery() of the SQLiteDatabase class which returns a Cursor.
For this method you must pass 2 arguments:

• the sql statement which is a SELECT statement
• an array containing the username's value which will be used in the WHERE clause to return the password (if it exists).
  

---

This method will return the password or null if the username is not found in the table:

public String getUserPassword (String username){
    String password = null;
    SQLiteDatabase db = this.getWritableDatabase();
    String sql = "SELECT password FROM tablename WHERE username = ?"; 
    Cursor c = db.rawQuery(sql, new String[] {username});
    if (c.moveToNext()) password = c.getString(0);
    c.close();
    db.close();
    return password;
}

In this line:

String sql = "SELECT password FROM tablename WHERE username = ?"; 

change the names of the table and the columns to the names that you have in your database.