Re: [RDA-L] Part 2: Efficiency of DBMS operations Re: [RDA-L] [BIBFRAME] RDA, DBMS and RDF

Posting to RDA-L

On 15/05/2012 02:52, Karen Coyle wrote:

let’s say you have a record with 3 subject headings:

Working class — France
Working class — Dwellings — France
Housing — France

In a card catalog, these would result in 3 separate cards and therefore should you look all through the subject card catalog you would see the book in question 3 times.

In a keyword search limited to subject headings, most systems would retrieve this record once and display it once. That has to do with how the DBMS resolves from indexes to records. So even though a keyword may appear more than once in a record, the record is only retrieved once.

I don’t believe that is correct. That kind of search result should be a programming decision: whether to dedupe or not. It seems to me that a record with “France” three times in the record could easily display three times in a search result if you want it to. With relevance ranking, or ranking by date, etc. it makes little sense to display the same record three different times, although I am sure you could. Having a record display more often makes sense only with some kind of browse heading display but I have never seen that with a keyword result.

This is a great example of how our current subject heading strings just don’t function today, and they haven’t ever since keyword was introduced. Computerized records work much better with descriptors than with traditional headings, for instance, your example would be something like:
Topical Subjects: Working class, Dwellings, Housing
Geographic Subject Area: France.

Here, there is no question since “France” appears only once in the subjects.

Seen in this light, our subject headings are obsolete but nevertheless, I believe our subject headings with subdivisions provides important options found nowhere else, as I tried to show in the posting I mentioned in my previous message. But really, how the subject headings function must be reconsidered from their foundations, otherwise they really are obsolete.

The dictionary catalog really is dead, at least as concerns the public.