Basic Components of Circulation Control System
The main component of a circulation control system is the transactions or loans database. This database contains a series of records one for each transaction. Each record must contain:
- details of the document such as document number, etc.
- details regarding user such as user number, his address, etc.
- the data of the transaction such as issue or return date, etc.
It is possible to use a Database Management System for the creation of the transactions or loans database, which is a set of three files, one for bibliographic details, one for user information and a third for transaction records. The last file may use numbers which have appeared in the other two files and might thus permit the merging of these three files when required (i.e., for sending the overdue notices). Online searching is possible for overdue and reserved items. Also report generator facilities will allow production of any relevant notice using the information contained in the three files.
It is common to keep bibliographic details in a separate file. Generally, this database is same as the catalogue of collections acquired for the library. It provides information on titles, authors and publishing details. Some of these details are used in notifying users the overdues.
Most of the packages for circulation control use bar-code readers as the simplest way of matching reader and the item (i.e., at the time of loan transactions). Alternatives such as keying in names and titles at each transaction, or numbers for user and the item (document) borrowed, are time-consuming and prone to operator errors, unless the software includes an error-trapping routine for the number input.
It must be mentioned that in the specification of a circulation control system there are a number of points to be kept in mind, other than the obvious one of whether the package has the capacity to handle all the loan records. Messages relating to various functions will be required and will include the fact that an item is overdue or that a user has other overdue items; that the item is required for or the user has exceeded his loan entitlernent. The system may have to cope up with the varying loan facilities for different categories of user, as well as different loan periods for the different types of material. All these are essential points which need to be ensured for the effective management of any circulation control system of a library.