You can link files together at File>Manage>External Data Sources.
This is only possible by doing a substantial amount of detail work.
It will not be a simple process.
See this nearly identical discussion:
This is true. You will also notice that the way the some starter solutions use user editable primary keys is not what you really want to be doing. I had someone using Invoices starter and they kept losing entire invoices if an invoice number was edited.
Ok, it is going to take time. I am patient. Do you think it is better to leave the solutions separate and just link the CUSTOMER with the other solutions, or spend time to regroup theme into one?. If so, last week, I imported into the INVOICES solution:
PROJECTS tables (Projects, Tasks, Posts and Contacts), copied layouts, scripts and remade relationship one by one with FM Advanced. Is this the way to do it? I just want to start the right way.
There are template solutions... I mean "custom apps"... that have these integrated and many you can find in the "Made for FileMaker" Made for FileMaker One that seems rather popular is the one from RCConsulting that they give away for free as a way of marketing their consulting services. It is called FM Starting Point and it is a fully open solution that you can further develop without limitations.
The FileMaker templates are not integrated, were not developed together, and really are more examples of what can be done than great templates. I see them more as marketing tools than real developmental tools.
I wouldn't link all of those starter solutions together. I'm sure you want to get up and running. But if you link 4 files together, as a beginner, you will have a very large solution and virtually no knowledge of how it works.
I found the starter solutions more like examples of what could be done as opposed to the best way to accomplish each of those tasks.
IMO, FM Starting point would be a better place to start.
And an even better place would be to learn how to build your own. I tried linking Contacts and Invoices. Besides not really loving either solution, and worse together, I invested the time in learning how to build my own.
Here's (to me) is one of the best places to start:
You'll build a contact/invoicing solution from scratch and learn beginner, intermediate and advanced techniques.
I still go back to my videos (V12) and as I improve my solution and skills, find 'new' things to learn.