InfoPath Dev

New to Infopath and Sharepoint - have relational db background, that habit may need to be broken

Using infopath 2010 browser form, sharepoint 2010 enterprise

I have a sp list with fields: description, category, and status

On the form are three multi select list boxes that use the sp list filtered on category and status.  Status is being used to only pull the "Active" items in the list.  Is this type of historical integrity check needed in SP or best left in the db world?  Is this a "bad" practice? 

The list boxes are being filtered on the control properties data connection.  Would it be a better practice to have three unique SP lists and remove the filtering?

Each item selected in the list box forces a postback to the server and the "Sending data to the server" message displays even though the control browser setting is set to never postback.  How do you work around this?

Appreciate any guidance.

Filtering can be done on two levels: at the DB level and at the SP/InfoPath level.  There are advantages to both.  Typically I would recommend at the DB level since this will only access the necessary data from the DB instead of all the entries.  If your data set is very large, I would definitely recommend this approach.  The SP/IP level could be advantageous if your data set is small to optimize for performance.  This would prevent multiple round trips between the form and the DB, but will require pulling in all the data at form load time.

I would recommend a single SP list and using filtering.  This will allow maintaining the list simpler than if you have 3 separate lists to manage.  It would also mean less data connections which is cleaner.

I believe filtering requires a postback in most cases, so I'm not sure if there is an easy workaround for this message.  You mentioned that you set the control to never postback, so that doesn't seem to be a good solution.  Loading all of the data at form load might solve the postback, but not entirely sure.