Question

The code below gets the information i require from my database but is not printing out all of the information. Firstly i know it is getting all of the correct information from the table because i have tried the query in sql developer.

public static void main(String[] args) {
    Connection conn = null;
    Statement stmt = null;
    ResultSet rs = null;
    try {
        conn = getConnection();
        String query = "SELECT menu.menu_id, menu_title, dish.dish_id, dish_name, dish_description, dish_price, menu.week_no "
                + "FROM menu, dish, menu_allocation "
                + "WHERE menu.active = '1' "
                + "AND menu.menu_id = menu_allocation.menu_id "
                + "AND dish.dish_id = menu_allocation.dish_id "
                + "AND menu.week_no IN (09, 10, 11)";
        stmt = conn.createStatement();

        rs = stmt.executeQuery(query);
        MenuList list = null;
        while (rs.next()) {
            list = new MenuList(rs);
            System.out.println(rs.getRow());
        }
        for (int pos = 0; pos < list.size(); pos++) {
            Menu menu = list.getMenuAt(pos);

            System.out.println(menu.getDescription());
        }

    } catch (Exception e) {
        e.printStackTrace();
    } finally {
        try {
            rs.close();
            stmt.close();
            conn.close();
        } catch (SQLException e) {
        }
    }

}

The output from the terminal is as follows:

 3 //Number of rows
 Fish and Chips //3rd row
 Chocolate Cake //2nd row
 //Here should be 1st row
 BUILD SUCCESSFUL (total time: 2 seconds)

Even though it says there are three rows it has only printed the two. Can anybody see if there is a problem with the above?

Answer 1

It’s hard to be sure without seeing the code for the MenuList class but I don’t think you need to loop over the ResultSet as MenuList does that for you.

As the MenuList constructor takes the ResultSet in rs as a parameter it probably loops over the ResultSet to create its entries. As you’ve already called rs.next() in the while of your loop the MenuList misses the first result.

I think you should replace all this:

MenuList list = null;
while (rs.next()) {
    list = new MenuList(rs);
    System.out.println(rs.getRow());
}

With:

MenuList list = new MenuList(rs);