First of all, thanks to everybody in that forum.

I only use it from some weeks, but it is so rich in ideas that I decided to completely personnaly redesign my DB, taking few days out of work every week for that purpose.

Even if this could take a big time, as a small business entrepreneur in ceramic retail, I want to use FM Pro at the max level, even implementing an accounting interface.

Here is what I've done for the moment, and why I need some advice before going any further.

My general DB is mainly created with Clients DB, Suppliers DB, Product DB, Purchase Order DB, Proposal DB, Customer Order DB, Delivery DB, Invoice DB, Transportation DB, Net Price DB, Inventory DB, and a Central DB that compills all informations per line item.

I created a Tab Bar structure in my DB and remodeled all my DB and layouts for that purpose.

While I was working on this, file by file, I noticed that the relational tools of FM allows me to execute all the client operations from the Client DB, using portals and scripts linked to the Central DB, without having to go to "Proposal Db", "Customer OrdersDb" as I first wanted (as a logic for Tab Bar Structure)

At that point, I am wordering if I shoud procede in this way, using the Client DB as the main file for all Commercial Issues (Selling), the Supplier DB for all Purchasing and Transportation.

That means that the other DB could be non visible, only accessible for entering datas from scripts, as a "stock of information" with only some layouts (in case of), using the Central DB for every print layouts (Invoices, Proposal, Orders...) as I finally discovered the benefits of non printing portals.

Does anyone have any suggestion at that point, as I discovered that remodeling a DB is such a hard work and that a bad structure can leads to big troubles

It looks to me OK and you are on good track.

Small point -- never use repeating fields.

Never use single field for Name and Family name etc.