The data store concept
A data store provides a mechanism to update or consult data that will persist beyond the scope of the current process. It enables storage of input message flows, and their retransmission via one or several output message flows.
Introduction to the data store concept
Depending on the context being described, HOPEX System Oriented IT Architecture offers the use of RE or RDB data stores.
Relational Database data store represents a data store in the form of tables or table views.
A Relationship Entity data store describes a database in the form of entities or classes.
A data store references an data domain.
A physical RDB domain is held by a database. An RDB information storage structure is held by a package.
If you describe an application system, only physical data stores can be used.
A physical data store represents the implementation of a logical data store.
If you describe a logical application system, only physical data stores can be used.
A logical data store represents the use of data via application systems without considering how their access will be concretely implemented.
Last but not least, HOPEX System Oriented IT Architecture is used to distinguish data stores local to a system from external data stores that are positioned on the border of diagrams.
A local data store represents a data store used only inside the system described.
An external data store represents a data store used inside and outside of the system described.
Usage contexts
Data stores can be described in the following diagrams:
• application system structure diagrams
• application structure diagrams
• Logical application system structure diagrams