Android-SQLite: How to Count specific value from Column?
- by sanpatil
I have two table (TABLE_EXAM,TABLE_RESULT). Here is value of my TABLE_RESULT.
result_id exam_id question_id correct_answer
1 2 4 y
2 2 5 y
3 2 6 n
4 2 7 y
I need to count how many correct_answer='y' where exam_id=2.
I try following code but it return 0.
public int calculateResult(int examId,String confirmAnswer)
{
int correctAnswer=0;
try
{
SQLiteDatabase db=this.getWritableDatabase();
String selectQuery=("select count(correctAnswer) from result where exam_id ='" + examId + "' and correctAnswer ='" + 'y' +"'" );
// String selectQuery=("SELECT COUNT(*)FROM result WHERE exam_id ='" + examId + "' and correctAnswer ='" + confirmAnswer +"'" );
Cursor cursor = db.rawQuery(selectQuery, null);
if(cursor.moveToLast())
{
correctAnswer=cursor.getInt(3);
}
}
catch(Exception e)
{
e.printStackTrace();
}
return correctAnswer;
}
In variable confirm_answer i pass "y".
Give me some hint or reference.
Any help is appreciated.
Thanks in Advance
