[EoDsql-users] Adding elements to a (disconnected) DataSet

[Ricardo P. <rpm...@ya...>]

Hi,

First of all, thank you for the 0.9 beta release, Jason. The site new
look is nicer, too.

At this moment I have in my program some classes whose persistence I
wrote before I know about EoDSQL, and I want to change that so all of
them use EoDSQL. Up to now, every entity in my database model has two
Java classes (three where EoDSQL is not yet used):

- ASimpleClass
- ASimpleClassList

ASimpleClass represents a single element, whereas ASimpleClassList
implements or extends things like MutableComboBoxModel or
AbstractListModel. This way, I have an easy way to put GUI controls
(JList, JComboBox, etc.) to access to the underlying database table.
I've even dared to use DataSet as the in-memory list view of the
database table (I'm using tables with very few rows, 10 or so).

Now, in a specific entity (VERSION, which represents versions of
products and could have a UNIQUE constraint on product + version
fields) I have the need to add a "fake" element, like a "*" wildcard.
It will be used in a JComboBox and won't be persisted in the VERSION
table. To put some context on the why I need it, I have another table
"ROLES" managing permissions, in which I want to be able to have rows
like:

Row  Meaning
--------------------------------------------------------
1    UserA is owner of productA, version 1.0
2    UserB is owner of productA, version 1.5
3    UserA is translator of productB, version 2.0
4    UserB is owner of productB, version *

as a quick way to make userB owner of every possible version of
productB (row 4), instead of requiring a new row every time a new
version of productB is created and, at the same time, allow different
users to be owners of different versions of the same product (rows 1 & 2).

Obviously, the "*" fake element in the VERSION in-memory list would be
used in a JComboBox in the ROLES management window.

Now, I'm not really sure if I could simply add an element to the
DataSet in disconnected mode and use it in the JComboBox model like a
simple List. I never write back the DataSet to disk; every time a
record is added, modified or deleted, the query is re-executed and the
DataSet is disconnected. I *believe* I may be in the safe side, but I
don't really know for sure. Is this a sensible approach?

TIA