In pkgdb which field records whether a package is manually installed

[Mayuresh <mayuresh%acm.org@localhost>]

I am planning to write a utility to keep my builds (pbulk.list) and
installed packages in sync.

Roughly the idea is to extract PKGPATH from the pkgdb and compare with
pbulk.list for manually installed packages.

Is the information that whether a package was manually installed or got
installed as a dependency captured in some field and which field is it?

-- 
Mayuresh