The pdb file format is not really a "particular" format. That pdb might be
pictures, or text, or appointments. So, the internal format of that data is
whatever the original designer of the product made it. It might not even be
data in a table with columns and rows. Fact is, all palm files are .pda
files..and it is your guess as to what the format is, or even what kind of
data is in that file.
I would talk to the person who gave you that file, or contact the company
that produced the file.
Perhaps the application has some windows part that allows export of the
data.
However, just throwing some pdb file out at ms-access is not even close to
being workable. You can't for example import or open a word document with
ms-access, as it can't know what to do with a document. You also can't open
Word with Excel either.
There is no way for ms-access to make sense of a file that could have a text
document, pictures, or perhaps it has quicken accounting data.
What you do need is to go to the original software and see if some options
export to text (comma delimited for example). If you can get the data to
comma delimited, or even to Excel, then you can eventually import it into
ms-access.