When are expression fields set (loaded/available?)

Hi Alex,

Expression fields will update on the basis of data in your screen. When I try this in the project I work on, it works like a charm. Most importantly, what is the code behind you expression field? What does it select and how?

My project example:

select t.translation
  from translation t
 where t.name = t1.name

The expression field should use t1, because t1 is the table alias of, in your case, Shipment. Probably your code should look like this:

select d.departure_time 
  from departures d
 where d.ship_id = t1.ship_id

Hope this helps your further!

Kind regards,
Mark Jongeling

Hi, well it works fine. Without saving. But only when we use an already existing record in Ship.

When adding a new record in the table Ship (through Shipment [looking glass]) it does not. 

So I assume my query is ok, but that somehow the app loads the newly added record after me saving the Shipment-record. 

Hi,

I now understand what you mean. It looks like the GUI doesn't use/show values that are freshly new. Sounds strange to me. Could you report the issue in TCP with screenshots and perhaps a video of it? My colleagues then can assess it and fix it 

Kind regards,
Mark Jongeling

@Mark Jongeling  you can reproduce the issue I understand from your reply? 

Sure, will do. Would be a nice  fix. 

I currently can’t reproduce it because in my project we don't use many expression fields this way. We save the data in database fields, that way it's possible to fill them with the default procedure. Then this issue doesn't present. But I do understand what you meant, hence my words.

Hello Alexander,

Yes, this is as expected/designed;

Expression fields are set after confirming your action (in this case saving the record of ‘Shipment’), because expression fields CAN have a lot of impact (for instance, a heavy query in this expression field). If this expression field would be activated after every user action in the form, this could negatively influence the performance of your application.

The way to achieve your requested ‘refreshed’ data, is to use database fields under ‘Shipment’, which are maintained with a default procedure, which alter the data directly when you add/update/delete an underlaying detail (Ship).

Hi Bart, 

I do get the feeling that Expressions work instantly when I use already existing data. So this only goes for newly entered data? For example, when I entered a weight in metric, the expression with the imperial is shown instantly. 

So, is there a difference between newly added Ship and already existing ships? (the data in this case). 

Alex