Which Pattern Most Closely Matches Scenario Detailed And Is It Good Practice

I have seen a particular pattern a few times over the last few years. In the UI, each new record (e.g., new customers details) is stored on the form without saving to database. This clearly has been done so not clutter the database or cause unnecessary database hits.

While in the UI state, these objects are identified using a Guid. When these are a saved to the database, their associated Guids are not stored. Instead, they are assigned a database Int as their primary key.

The form can cope with a mixure of retrieved items from the database (using Int) as well as those that have not yet been committed (using Guid).

When inspecting the form (using Firebug) to see which key was used, we found a two part delimited combined key had been used. The first part is a guid (an empty guid if drawn from the database) and the second part is the integer (zero is stored if it is not drawn from the database). As one part of the combined key will always uniquely identify a record, it works rather well.