游标索引越界异常

打开后出现光标索引越界错误 数据库 。请任何人告诉我如何打开现有数据库 sqllite-Android .我想在数据库上触发一个选择查询 检索一些信息？

            public void getPatient(SQLiteDatabase db, String name) {
    // TODO Auto-generated method stub
    db=this.getReadableDatabase();
    //db.open();
    System.out.println("in cursooooooooorrrrrrrrr");
    Cursor c = db.rawQuery("SELECT * from table_patient WHERE COL_Name"+"=?", 
            new String []{name});           
    //c.moveToFirst();

    int index = c.getColumnIndex("COL_FirstName");
    System.out.println("First Name : -----------  "+c.getString(index));
    c.close();


}

像这样做：

int index = 0;

if(c.moveToFirst())
    index = c.getColumnIndex("COL_FirstName");