Introduction to Custom Logical Unit

A Custom Logical Unit (Custom LU) is an object that manages some business information in IFS Applications. The business information is defined by the Custom Attributes belonging to the Custom Logical Unit. It is possible to configure custom logical units and make them available for users in IFS Applications. To enter the information that a Custom Logical Unit represents in IFS Applications it is possible to create a Custom Page for it. The Custom Page will present the Custom Logical Unit information and provides functionality to modify it. The information that a Custom Logical Unit stores can be referenced and shown in other IFS Application pages or Custom Pages. 

Contents

• Attributes
• Business Logic
• Architecture
• Restrictions

Attributes

The attributes describes the essence of the Logical Unit. There are three main types of attributes, but only the types Persistent and Read-Only are supported for Custom Logical Units.

• Persistent- Attributes of different data types that store data.
• Read-Only - Attributes that fetches its value from other attributes or as a composition of other attributes.

Business Logic

Custom LUs can be used with e.g. the following features/concepts:

• Custom Page
• Custom Fields
• Custom Defined Events
• Custom Menu
• Quick reports (Custom Reports)

It is not possible to directly add business logic to a Custom LU, e.g., validations. It is possible to achieve some logic and flow by using Custom Events and Custom Menus. Referencing a Custom LU from static source code is however not supported. See more about this in the restrictions section.

Architecture

The architecture of Custom LUs is similar to that of standard Logical Units'. As a Custom Logical Unit is deployed, it only resides on the server. It is accessed from the client when it is connected to a Custom Page. The Custom Logical Unit consists of the following database objects.

• Table - Handles storage of records. The table is named [LogicalUnitName]_CLT and has ROWKEY as its primary key.
• Package - Handles modification of records. The package is named [LogicalUnitName]_CLP.
• View - Used for presentation of records. The view is named [LogicalUnitName]_CLV.

The configuration of a Custom LU is stored as meta data in the database. When a Custom Logical Unit is deployed it's meta data is used to create the database objects needed. The meta data is also used to define a Custom Page that is associated with a Custom Logical Unit. 

Restrictions

New development or customizations of application source code should never make use of a Custom Logical Unit. There are technical limitations as well as maintenance issues with such an approach. Writing business logic including a Custom Logical Unit is not supported by IFS or IFS Development and Deployment tools. In other words, writing static code that references configured objects is not supported.