Setting Up Relationships to gather data for report

[Teutonic_Night]

I'm working on a smallish database for taking inventories of various types of items. This is mostly just for my own use, both for convenience and for more practice with FileMaker Pro.

Anyway, I have a number of tables created, with each table storing a specific category of item- one is for books, another for videos, etc. I went with separate tables since there are only a few common fields between the different tables. I have a single layout for each table for data entry and searching. Eventually, I'll likely add different layouts for doing different tasks. Anyway, what I'd like to create is a layout that lists the total cost of items on a single layout. For example, I'd like to show the total cost of books, the total cost of videos, and then a sum of the two. I don't want any other information visible (for now). It seems like I need to set up a number of relationships in order to do this, but I'm at a loss of how to structure these relationships. Can anyone give me some pointers as to how to go about this? Thanks!

[dkemme]

Might be better to have only one table, even if fields are not in common, if you wish to display the data in a common area at some point. For the fields that are not in common, give them a generic name in define fields and a specific name on the layout for entering the data. Give each record and identifier if it is a book, video... to allow sorting for type of asset. Use summary fields to add up cost and you are done.

[Teutonic_Night]

I had thought about doing that, but some categories have a lot more fields than others, and I was hoping to avoid having lots of non-applicable fields on many layouts.

I was wondering, though, that maybe creating another table, and having that table be related to all of the others might be the way to go. I could create fields in this new table for each categories summary fields, and then just add fields in the future if I happen to create any new categories....