Hi Clyph,
Here's the answer I posted to a similar question last year:
BEGIN
This could be tricky. MARC records have a very flexible
structure to accommodate unstandardised and loosely structured
bibliographic data, and can contain fields with multiple values
(or multiple subfields). By contrast, relational databases like
Access by definition use a rigid data structure with precisely
defined relationships between items.
It's perfectly possible to design a relational database that
will accommodate bibliographic data; what's difficult is the
business of converting loosely structured data such as MARC
records into a relational structure.
Depending on your needs, it may make more sense to import the
data into a free-text database such as Bekon Idealist or
AskSam, or of course to use a specialist bibliographic
database.
That apart, the basic approach will probably be to convert the
MARC data into one or more textfiles that Access can import. My
own preference would be to do most of the work at the textfile
level (using Perl, mostly), to produce simple tab-separated or
CSV textfiles ready to import into Access tables. This is
simply because parsing textfiles is much easier with Perl than
with VBA.
There are some MARC tools here
http://lcweb.loc.gov/marc/marctools.html, and a Perl project
for working with MARC records is at
http://marcpm.sourceforge.net/. I expect that there's a
librarians' mailing list somewhere that has discussed the
details of all this;
Hope this helps. With luck someone more knowledgable will point
you straight to a ready-made answer.
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Unfortunately, no one come up with a better answer.