Re: modelling history in a database

stu wrote:
> > Second, you could create a table Change that has fields for the table,
> > field, old data, new data and date of change.
> I like that idea! Have you tried it in practice? Does anybody else have
> any comments on this suggestion?

I was considering doing this for a project I'm involved in. It's a coursework marking system, where coursework and question definitions are spread across several tables. I was considering a version history using a serialized LOB (i.e serialized all the objects, then save them to a blob) giving only one backup/version table covering data in several tables. This may be a good way if there's lots of complex data changes and the only retrieval likely is simple reads,

In this case the schema would be

	table change(
		id_of_thing_being_changed references id_of_current_thing
		date_of_version date
		definition blob
	);

Richard Received on Fri Feb 14 2003 - 12:16:45 CET