You can calculate elapsed time with timestamp fields just as you can with time fields. They both store data in seconds, but use formatting to display date and time or just time. Timestamp2 - Timestamp1 produces elasped time in seconds just like TimeField2 - TimeField1. The key difference is that if 12 midnight should fall in the interval between the two times, the calculation using timestamp fields will still correctly compute elapsed time and the calculaiton using just time fields will not.
It appears that you deleted this field from your layout, but it then remains defined as part of the table where the field is defined. In FileMaker, you get three objects with identical names, tables, layouts and table occurrences. Though you get a table occurrence and a layout of exactly the same name when you add a table to your database file, they are not the same thing.
You can export data from fields even if they are not visible on the current layout, but it would be a good idea to create a layout where all fields to be exported are visible. You can create a new layout that lists fields from the same table or you can just switch your view to table view and use the modify button to add the additional fields to your table view.
You can add fields to your view even if they were defined in a different table as long are there is a relationship joining the two tables. The same is true for exporting data from more than one table in the same export.
1. Since Timestamp wil always be accurate in calculations, in what instances is 'time' advantageous/useful where timestamp is not.
2. So because I want to export many of the fields from multiple layouts, including invisible ones, would I be best having a 'master' layout from which I can export all fields to Excel, but relate fields to other layouts? And when I get to produce an iPhone solution, I assume I can hide the 'master' layout with the subsiduary layouts being the 'front end' of the app.
1) Time fields do not require entering a date so they can be easier to use when the date or the midnight hour is not an issue.
2) I suggest looking up export records and save as Excel in FileMaker Help. It really isn't a case of having the right layout as much as it is what tables and relationships you have in your database that determine what you will get when you export to excel.
Re. 2. So if I have a layout that contains most of the fields required to be exported as Excel, and this layout has relationships to the other fields I need exported, then that would be a way to get the 'complete' export.
Layout is the wrong term here. Tables are related to other tables, not layouts. Each layout in your file is based on a table by specifying a table occurrence in "show records from" in layout setup. You can create any number of different layouts that all specify the same table occurrence and thus all use the same data source table and link in the same manner to other related tables.
I can only answer "Probably" as I do not know how your data is structured nor what you want it to look like when you export it to excel.
Thanks, I think i get what you mean.
Background: I'm hoping to create a solution that will have a 1y renewable activation license. If there user chooses to not renew, I want them to still be able to retain critical raw data, hence the need to have a table including all the fields. That will probably be quite a pain to use, but necessary.