Hi Steve, I'm the librarian of Horowhenua Libraries, for whom Koha was written. A little history - we used to import MARC records, but a fairly rudimentary study indicated we spent more time trimming down MARC records that it took us to catalogue from scratch. We buy from a wide variety of sources, many of whom overlap in stock. So it is imperative to get the order information into the system immediately an order is placed, to avoid double ups. For this to happen, we have to type the data in. So when the MARC record becomes available, we already have half the data we need on the system. We used to overwrite our order with the MARC data, then trim down till we liked what was left - and it took longer and was more expensive and less convenient than adding to what we already had. All of which is by way of explaining that yes I know what MARC records are, and that lots of libraries love them, but we don't, and since Koha was written to cope with what was important to us, we didn't bother.
MARC records have an astonishing amount of detail, both in terms of data about the book, as well as ways in which the data can be described. I'm wondering how I should handle the first difficulty: subject headings. MARC records have several different entries for subjects:
650 Subject added entry -- Topical term
Subjects like Mammals, Nuclear Warfare, Law, Alcohol, Child Welfare, etc. Appears to be the most common type of subject entry, at least with my data.
651 Subject added entry -- Geographic name
Subjects like Canada, Rome, Moon, China, British Columbia, etc.
600 Subject added entry -- Personal name
Subjects like Plato, Helen Keller, Charlemagne, etc.
In addition each subject entry also specifies a source "system" such as Library of Congress Subject Headings or Sears Subject Headings.
We use all these types of subject headings. Our headings are LC, with some local additions, and a few substitutions where LC uses a term that simply isn't used in NZ. But the patterns follow the LC patterns, even though we don't bother differentiating between 600, 650 and 651 headings.
Obviously Koha doesn't have this complexity of subject headings, and probably doesn't need it, but I'm suspecting that we probably don't want to mix subject headings from different cataloging systems. Any possibility of adding a field to bibliosubject to specify a subject heading system used?
Also, should I be adding any subject headings gathered from MARC records to the catalogueentry table (which I assume is used to deter librarians from adding new, conflicting subject headings like "Cows" and "Bovines").
I know Chris has told you about Subject authority files, which is what warns us against using new terms which may be conflicting. Hope this is some help. Sorry I can't help with a file of "proper" LC headings! Rosalie _____________________________________