Persistent URLs

We have persistent URLs of the forms:

• http://copac.ac.uk/crn/<copac-record-number>
• http://copac.ac.uk/crn/<copac-record-number>/html

The first url gives a MODS XML record. The second gives an HTML display. You can find urls like the second one embedded in all our Full Record display web pages. If you are creating your own links then the Copac Record Number can also be found in the <recordIdentifier> element of our MODS record

Permanence of URLs

The Copac database isn't static. We process approximately one million updates a month from our contributors. When a contributor deletes a record from their catalogue then the corresponding record on Copac will also be deleted. Hence our persistent URLs are not guaranteed to be around for ever.

The Copac record number is based on the contributors own record number. We usually normalize the number and add our own Contributor prefix. Contributors often move their Library Catalogue to another software vendor's product and when this happens it can cause record numbers to change. This has the trickle down effect of changing all our record numbers for that Contributor.