I think you'll find this a worthwhile read: http://paulstack.co.uk/blog/post/have-orms-introduced-extra-complexity-into-our-codebase.aspx
On Sep 1, 3:59 am, jwz <[email protected]> wrote: > I'm new to VB.NET, after using VB6 for a decade or so. A friend and > some books are what I'm using to learn. My friend taught me about the > Data Access Layer, and I've created some simple classes for simple > tables. For example, I have a supplier class for the supplier table, > and a part class for the part table, and an order class for the order > table. Each class provides the ability to read, update, insert, > delete, etc., its table. > > My question comes in when I need to join tables. For example, if I > want to join the part table and the order table, each class only knows > about its table. The select statement in the part class doesn't have > access to the column definitions in the order class, and vice versa. > > When I asked my friend about this, he said I should create a Join > class. In this class, one of the classes, say the part class, is > inherited, but I need to define the fields from the order class that I > want to retrieve. > > My problem with this is that if I have several of these join classes, > then I've duplicated several table definitions, and if I change a > table in the database, I have to change not only the class that > represents that table, but I also have to track down all of the Join > classes this table is defined in, and change them. > > It seems like there should be a better way, but I haven't been able to > find it. > > Should I include all of the tables from the database into a single > class, so that I can reference any table that I need to join? > > Is there some other, better way? > > Thanks for the help. > > Joel -- You received this message because you are subscribed to the Google Groups "DotNetDevelopment, VB.NET, C# .NET, ADO.NET, ASP.NET, XML, XML Web Services,.NET Remoting" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/dotnetdevelopment?hl=en?hl=en or visit the group website at http://megasolutions.net
