Anyway, somebody should finally fix that db omission from the uses clause (when using Lazarus and creating TDataset and fields in code). It is hard to know and find for average users.
I read your bug report. Just as hint. It works semi automatic with package Cody (this is that one, I never miss to install on a new Lazarus installation).
Try to compile your code without "db" in the uses clause:
-> a error is shown in the message window "project1.lpr(21,27) Error: Identifier not found "ftInteger" "
-> now right-click on it and click on "Show Cody Dictionary for "ftInteger" "
-> select the first entry
Thats it.
Cody is learning identifiers by programming. For me, it saves a lot of time!