Abstract business entities are mostly used when you want to store a table of data. For example, you read data from a csv file and with the abstract business entity, you can map the fields to the csv columns. Abstract means there is no third party system behind, but it can be used equally to a business entity mapped to a third party system.
To add an abstract business entity, open a model in the Business Entities designer. Drag and drop a new Business entity item to the canvas. Right-click it and select Field definitions.
In the wizard, click Add field and choose a name and type for it.
A default value can be configured here as well as the option if it is Required and Read-only. The field can be removed with selecting it and click Remove field afterward. The field can be selected by clicking the -symbol.
When you finished adding, removing and configuring your fields click OK and save the model.