Do rules move to virtual tables

[avianmanagement]

If on a table we have

ALTER TABLE customer;
ALTER COLUMN available CALCULATED limit-balance;
ALTER COLUMN limit RECALCULATE;
ALTER COLUMN balance RECALCULATE

will that move over to a virtual table if it has those fields in it and work right away in the UI, or would it wait until the data went back to the table itself?

[barrymavin]

will that move over to a virtual table if it has those fields in it and work right away in the UI

Please explain what you mean exactly.

[avianmanagement]

If we have a table set up as above so that the available column is calculated If I use this tables fields for my UI then it will work

If I use these fields in a virtual table where I have these fields and say other fields from orders etc.

If I use the virtual table to create my UI on the pages / forms will it work the same in the UI or would it wait until the data was written back to the table to fire the calculated field, or are they in fact the same thing in reality.

[barrymavin]

Calculated fields are calculated when read from the table. So yes it will work from the Lianja SQL server as well.

[avianmanagement]

Calculated fields are calculated when read from the table. So yes it will work from the Lianja SQL server as well.

OK now I'm confused, probably a misunderstanding of terminology on my part. You say these are calculated when read from the table, does that mean that in the UI using these fields from a virtual table, on the normal Lianja database rather than Lianja SQL server, would teh value in teh calculated filed alter on the UI when the user changed any of the other tow fields in the UI, in other words does the date in the form update in real time as the user enters or alters data.

[cyrilbaskir]

If on a table we have

ALTER TABLE customer;
ALTER COLUMN available CALCULATED limit-balance;
ALTER COLUMN limit RECALCULATE;
ALTER COLUMN balance RECALCULATE

David

Did you try this?
I typed it in at the console after Hank suggested I look at this. Didn't seem to do anything. Where does it go?

[barrymavin]

David

Did you try this?
I typed it in at the console after Hank suggested I look at this. Didn't seem to do anything. Where does it go?

Where does what go?

Just do this to see the dictionary:

use customer
list dictionary

[avianmanagement]

Just looked at a table and it's attributes and there is no way to set this in the attributes, so I guess you have to do it in code.

[barrymavin]

Calculated fields in a database table are readonly and are calculated when written or read from the table. They will only be refreshed in the UI if you issue a refresh() on the section or field.

[avianmanagement]

OK thanks for clarifying that for me , now I understand how it works.

So in the UI we would need to issue a Refresh() if any of the values changed in order for it to show up. This I guess we'd need to issue in the lost focus to make sure it always fired.