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De-duplicate authority headings

Learn how to remove duplicate authority headings in OLIB.

The de-duplication process can be used for both Titles and Authority headings. It is available for Titles, Series, Places, Publishers, Subject headings, author Names and Languages. In this example it will be used for publishers. When a record is de-duplicated all the linked items (for example Titles linked to a Publisher) are linked to the retained heading.

For example there may be 4 versions of the publisher McGraw Hill.

De-duplicate an authority heading

 Note: the De-duplication process is privilege controlled to those staff with Manager level privileges or above.

  1. Go to the authority heading domain e.g. Suppliers/Publishers.
  2. Search for the version of the heading to be retained and put the record into modify mode.
  3. The Duplicates link appears on the Controls sheet of the layout.
  4. Use the link to search for the publishers to be merged and insert them back to the correct form of the publisher name.
  5. When the record is saved the following prompt will be displayed:

De-duplication will be performed if this record is saved

Do you wish to de-duplicate?

  1. When you click Yes the de-duplication will take place.
  2. Refresh the search and note that the incorrect versions are no longer present. When you display the full details of the correct heading it can be seen that all the Titles are now linked to this publisher.

The field is only visible on the layout in modify mode.


To de-duplicate Title records, follow the same procedure as above, using the Duplicates link on the Controls layout.

When you save on a Titles de-duplication process, OLIB links all versions of the subjects, authors, series etc.. authority headings, to your preferred title. Copy records are also moved across into the preferred title record.

You can configure whether or not only the Copies data is moved across from one title to the preferred title. If only the Copies data is moved across, the audit and transaction history are still also retained.

To do this configuration use De-duplicate Copies Only Y/N

Set this value either in:

OLIB domain   Behaviour
System Administration> OLIB Defaults The Yes or No value takes effect when running the de-duplication process across all Titles layouts (RDA, General etc..)
Titles> Admin (RDA Layout) 

The De-duplicate Copies Onlyfield will need to be added to the layout by the System Administrator, using Layout Manager. (Suggested placement: above the Duplicates field).

If this value is null, the setting in OLIB Defaults will take effect.

Titles> Related Items and Control data (other layouts)

If you want to apply the same policy for Title and Copies duplicates on a system wide basis, regardless of the layout, then set OLIB Defaults: De-duplicate Copies Only to Yes or No.

If you want to address de-duplication on a record by record basis, then the System Manager should add the attribute to your Titles layout, e.g. Control details or Admin sheet, above the Duplicates field:

  • De-duplicate Copies Only? (ti_dedupe_copies_only)

Example procedure in titles

If you want to de-duplicate copies on a Title record by record basis:

Leave OLIB Defaults: Cataloguing Defaults: De-duplicate Copies Only set to NULL.

  1. Search for the relevant Title in Titles.
  2. Add 1 or more duplicate titles to the Duplicates field.
  3. Set De-duplicate Copies Only:
Yes OLIB will transfer only Copies data to the preferred Title. The other linking records (publication record, physical, series links, …) are simply deleted along with the title that is being deleted. The authority data will be subject to the normal rules regarding the removal of publishers, authors etc that are no longer referenced by any titles.
No OLIB will transfer across Copies data and other authority headings, e.g. Authors, Subjects, Classes
  1. Save the Title record for the de-duplication to take effect.