Automatic check when entering the same shelf mark twice

Some libraries use a classification for their titles that sets an obligation to use unique shelf marks, such as a library using a classification with current numbering (shelf mark composed of a class mark and a number giving the title place in the selected class mark).

Example : the shelf marks BIOL 122, BIOL 123, BIOL 124, LIT 164, LIT 165 could be used for four titles about Biology and two titles about Literature. The number tells the order of the titles on the shelves.

With such a classification, each title should have a unique shelf mark. In order to prevent giving the same shelf mark twice, BiblioMaker can be set up to display a warning when entering the shelf mark :

In the Titles file, open the Options (with the Action>Options command) and click on the General button. Tick then the Single shelf marks check box.

Some classifications (such as the Universal Decimal Classification or Dewey) do not set an obligation for unique shelf mark (for instance, you could have several titles with a shelf mark such as 914 SMIT if their main subject is the European geography and have been written by an author called Smith. With such a classification, checking the uniqueness of shelf marks would be absurd.