Parent and Child item types allow you to create combined rules to incorporate several item type rules together.
In the circulation and fine rule matrix, there is the ability to limit the number of checkouts by item type. However, a further option exists for libraries that would like to expand this rule to include several item types under this same number of checkout rule. For example, DVD and Blu-Rays, these could be separate item types in the library system, however, instead of putting a limit of each of these, a library could create a combined rule to incorporate several item types together. To accomplish this, Koha has Parent Item Types.
Creating Parent Item Types
Note: A single item type can be a Parent to any number of other item types, but any given item type can only have one Parent. Additionally, an item type with a Parent cannot be a Parent itself.
First, in the Item Type configuration in the Administration module, edit an existing Item Type. There, you have the option to set a Parent Item Type. Defining a Parent type will apply checkout limits for all Children as described on the circulation rules page.
Creating Circulation Rules
Once you have a Parent item type, you can start using those relationships in your circulation rules.
- In the circulation and fine rule matrix, when selecting an item type, there will be a new format for any Parent item types, in which you can pick either the Parent or one of the Children.
- In this example, because DVD is the Parent to BluRay, and BluRay is counted toward that DVD total, our patron is subject to both limits simultaneously.
Checkout Limits Only
As we go through the behavior of Parent and Child item types, remember it only applies to the value in "Current checkouts allowed." Any other values in the DVD rule (loan period, fines, renewals, holds, etc.) apply *only* to DVD checkouts, and any other values in the BluRay rule apply only to BluRay items.