Holdings or summary records RFC

Note: This page is obsolete. This RFC hasn't been implemented, please refer to newer MARC Holdings Records RFC for current discussion.

gmc wrote this RFC. Is it still relevant ? (paul_p thinks not) Does Koha have multi-tier approach yet? If not, this is still relevant.

RFC: Holdings structure

This specification adds summary holdings functionality to Koha. To achieve this, a number of architectural changes will take place. Previous releases of Koha used a two-tier bibliographic and item structure. Historic Note, Originally Koha had a 3 tier approach, this was lost when MARC support was added Bibliographic records store title-level data and item records store item-specific data. (At the database level, things are a little more complicated, but functionally this is accurate.) There are several functional shortcomings to this approach:

1. If libraries own materials that have not been inventoried at the item level, they cannot reflect these in their holdings without workarounds.
2. When a title has a lot of item records, it becomes difficult to display them clearly—the display becomes overwhelming.

Libraries want some way to:

1. Organize multiple items together so that it’s clear that items are related to each other.
2. Summarize the holdings from a group of items together, including expressing the gaps where items are missing from a set..

At the same time, some libraries do not want the overhead of an additional structure to support holdings. Many public and special libraries are not interested in adding summary holdings records. Libraries in many European countries also are not interested in maintaining holdings records. Holdings records must be optional for some libraries.

Holdings records add a lot of value for serial and multi-part records, but are not as critical for single-part monographic records. It’s important not to add overhead to the process for monographic cataloging.

A new kind of records, called a summary record, will be added to Koha. Summary records will be available to group item records and to contain summary information about the item records. The actual fields of the summary record will be very similar to the fields of an item record, although some item record fields will not make sense in summary records, and summary records will have some additional fields that don’t make sense for item records.

Since summary records, and holdings functionality generally, are basic to the system, adding them may change a lot of other functions in the system. As part of the analysis process we discuss a lot of these possible changes in order to be sure we’re aware of them, but they are not in scope for the first release of the holdings feature. The first release of the holdings feature will focus on the summary records that group items and store summary information. This will keep the scope manageable and will build a base for future functionality.