Persistency Management

To get this project working, the aggregate plugins and properties need to be set correctly. See for installation details this page.

The example project Career is a project that is used to demonstrate the functionality regarding persistency management. The following subjects play a role in this example project:

• Aggregate design (see also Aggregate)
• Singleton versus non-singleton
• Custom metadata
• Versioning
• Displaying aggregates in a list (see also Container type: AQ_Aggregate_List)
• Creating an aggregate (see also Service call type: AQ_Aggregate_Create)
• Reading an aggregate (see also Service call type: AQ_Aggregate_Read)
• Updating an aggregate (see also Service call type: AQ_Aggregate_Update)
• Deleting an aggregate (see also Service call type: AQ_Aggregate_Delete)
• Searching for an aggregate (see also Service call type: AQ_Aggregate_Search)

For more information on persistency management design see also Persistency Management guide.

For more information on the relation between aggregate concepts, see

Contents of the example project

The example project Career consists of two parts. The first part is about a single person and his jobs. The second part is deals with a non-singleton entity Course.

Person aggregate

The aggregate Person consists of the entities Person and Job, but the definition only contains Person. Aggregate functionality automatically creates, reads, updates and deletes all entities that are connected to the entity that is defined in the aggregate definition.

An exposed flow PersonManagement is available to manage person aggregates. As mentioned before, a person aggregate consists of a single person, with zero or more jobs attached to it.

Version management is enabled in the create, read, update and delete services so multiple version of an aggregate are available, as shown in the aggregate list below.

Shown is one aggregate about Tom Barman who - at first - has one job. In version 1 his name was misspelled, so this was corrected in version 2. At one point, Tom had another job, this is effectuated in version 3, the current version of the aggregate.

As can be seen in the example project, custom metadata fields can be defined for an aggregate. In the person example, the custom metadata fields FullName, Age and NrOfJobs have been added to the person aggregate. The first is a concatenation of two existing attributes, the second is a plain attribute and the third custom metadata field is a calculation of the jobs attached to the person entity.

CourseGroup aggregate

The course group aggregate only consist of the entity Course, which is a non-singleton. The create service for the aggregate CourseGroup is defined in such a way, that it is possible to save more than one course in such an aggregate. An exposed flow CourseGroupManagement is available to manage course group aggregates, as shown below.

A course has a duration in number of days and a price in euros. Custom metadata fields have been defined within the course group aggregate to summarize the number of days and the price and count the number of courses for each course group aggregate. Versioning has been disabled in this part of the example, so only the latest version of each aggregate is available.