On 20 Jun 2007, at 22:57, Ed W wrote: > > I think we are all agreed that snapshotting the invoice is a > requirement. But: > > - lets assume that most invoices contain the same address time and > time again, > - hence we start thinking about normalising that address record > rather than duplicating it endlessly
This makes perfect sense when you're a database programmer, but not if you're an accountant. Paper invoices have the address printed at the top of each one. Likewise invoices in Ledger should contain the whole address in each one, IMO. I see what you're trying to do, and if you're a database programmer or administrator you might think I'm crazy for suggesting this but IMO it's better to have duplicate data. When you normalise you make things more complicated and introduce the risk of a record becoming changed (linked to an different entity) after its been posted. I appreciate that good a programmer will endeavour to ensure that this never happens, but nevertheless from a certain perspective duplicate data in posted invoices _is_ "correct" - the address belongs _separately_ to separate records. Let's consider a "normalised" paper trail. We print out an invoice to send to the customer - it has their address on it, the details of items & services sold and a total amount owing. The logical thing to so is not keep a copy of the whole invoice but to simply record customer number, item numbers & amount in a ledger. But the tax man does not allow us to do this - he requires us to keep a whole copy of the invoice, wasting more paper and consuming much more space in our filing cabinets. Whether we produce it with carbon paper, a photocopier or by printing it out twice on our laser printer, our copy of the invoice has to be exactly the same as the one we sent out (not just the relational data required to produce an exact copy). Likewise Ledger should keep a whole copy of the invoice, and not to to take short cuts (however efficient they may seem). Stroller. ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ Ledger-smb-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/ledger-smb-devel
