Table of Contents
Limitations and Restrictions
A number of limitations and restrictions may be put into place by the system in order to determine the duration permitted in a circulation. In nearly all cases, limitations and restrictions may be overriden by the user however it is advised the calculated durations be observed as much as possible in order to retain consistency.
Limitations
Limitations usually do not prevent a circulation from taking place, but may influence when and/or for how long the circulation is permitted.
- Base Date - The base date is calculated as the current date, upon which the circulation is taking place.
- Circulation profile duration - A base duration is added to the base date based upon the circulation profile assigned to the Reader.
- Circulation Profile Media override - The circulation profile media override is added to the base duration if one has been set within the circulation profile. The override is not additive to the base duration, but instead replaces it.
- Item Media Override - The Item media override is added to the base duration if one has been set, and it has been permitted to override information provided by the circulation profile.
- Closures - A first stage incorporation of closure dates is added as a limitation. If the calculated due date after the inclusion of limitations falls on a closure date, the duration is increased until it falls on a date when the library is open.
- Booking date - The calculated date is limited by the first date upon which the Item is booked for an advanced booking. If the next booked date is the same as the base date however, and the Reader for which the booking has been made is the same as the Reader subject to the circulation, the circulation is deemed to be an execution of the booking and an offer is made to remove the booking.
- Reader expiry date - A limitation is placed on the calculated due date is the membership of the Reader is due to expire. Typically, the due date is calculated to be the day before the expiry.
- Item expiry date - A limitation is placed on the calculated due date is the available date range of the Item is due to expire. Typically, the due date is calculated to be the day before the expiry.
Restrictions
Restrictions are very often Yes / No decisions which will outright prevent a circulations from taking place.
- Media restriction - An absolute restriction is placed if the media type has been specifically restricted for circulation.
- Circulation profile restriction - An absolute restriction is placed if the circulation profile has been specifically restricted for circulation.
- Audience restriction - An absolute restriction is placed if the audience of the Item is deemed inappropriate for the Reader.
- Reservation restriction - An absolute restriction is placed if the Item has been previously reserved for another Reader.
- Reader or Item availability restriction - An absolute restriction is placed if either the Reader or Item is not yet active, either through their boolean checkbox, or via their date settings.
- Item Limit - The number of items already in possession of the reader has already reached the limit set in the reader circulation profile.
Rollback
If the ultimate due date falls on a closure day, the Circulations dialog then counts backwards to find the last safe day on which the Item is due for return. This is done so that the due date does not fall after an absolute limitation such as the library, Reader or Item no longer being available. It is possible therefore, that the calculation results in a due date that is the same as the base start date. If this situation occurs, so that the duration is now 0 days, the circulation is no longer permitted.
