SQL query to select maximum

Question

Dear all,
I have a table called "Orders" for a webshop that contains order ID, product ID, product quantity and price per unit. To insert a new order I want to get the highest order ID first and increase it by one, to be used as the new order ID.
Here is the code:
String orderIDquery = "SELECT MAX(OrderID) FROM Orders";
          int orderID = 0;
          try
               rst = stm.executeQuery(orderIDquery);
               if(rst == null)
                    orderID = 1;
               else
                    rst.next();
                    orderID = rst.getInt("OrderID");
                    orderID++;
          catch(SQLException e)
               out.println(e.toString());     
          out.println(orderID);For some reason, I get the SQL exception "column not found" from the "getInt" command, although the column by the name "OrderID" is clearly present in the table.
Any ideas what could be wrong?
TIA,
NetWundi

Answer 1

Dear all,
I have a table called "Orders" for a webshop that
contains order ID, product ID, product quantity and
price per unit. To insert a new order I want to get
the highest order ID first and increase it by one, to
be used as the new order ID.
Here is the code:
String orderIDquery = "SELECT MAX(OrderID) FROM Orders";[snip]
For some reason, I get the SQL exception "column not
found" from the "getInt" command, although the column
by the name "OrderID" is clearly present in the
table.
Any ideas what could be wrong?You don't have a column named "OrderID" in that Query. You can either refer to the column by number (1) or alias it in your sql and refer to it by the alias name (SELECT MAX(OrderID) AS SomeColumnName FROM Orders".
Good Luck
Lee
>
TIA,
NetWundi