PD.Relational Data Management

	PD	Relational Data Management	Version:	0.3
	Document type:	Pattern Definition	Owner:	S.A.D. Jumelet

Description

This Pattern Definition serves the creation of models in the Service Category "Data Management". This Pattern provides the means of "strictly structured data" handling, i.e. it controls the creation, updating and querying of sets of organized data. It is called 'relational data management', because a schema is used to store data in a predefined way, with predefined relations between data objects. The provisioning of the following elements is important with this kind of data handling:

a "modeling language", to define schemas;
a "query language", to enable data object reading, creating, updating, and deleting;
a "transaction mechanism", to enable interaction with other (instances of) data management facilities and applications.

These elements are provided by the Data Engine. Data objects are stored using a predefined (structured) Data Store. Both functions form the core of this Pattern.

Services realized

This Pattern realizes the following service(s):

Application Database (This service provides a data store for applications with a predefined structure)

Functional and Integration view

This is the graphic representation of the functional model of this Generic Pattern:

Relational Data Management pattern

Generic Pattern Composition

This pattern is an aggregation of the following (mandatory and optional) functions, expressed in Generic Functions:

Icon	Function	Inclusion	Rationale
	Data Engine	recommended	The Data Engine is the heart of the pattern, as it offers the intelligence to make use of the strictly structured data.
	Structured Data Store	recommended	This function is the foundation under the Data Management pattern. Data is organized in such a way, that information can easily be accessed, for example by a query.
	Controlling	recommended	When allowing consumers (such as users and/or administrators) the ability to change the configuration of the Data Management facility, special care may be required to prevent unauthorized access to data stored by the Pattern.
	Caching	optional	Since the Data Management pattern underlies many other infrastructure facilities and applications, there often are requirements to guarantee a certain performance level, for which this Caching functionality may provide a significant boost. However, caching introduces additional challenges related to data being consistent and up-to-date, security risks for sensitive data residing in cache memory, et cetera.

Services connected with this Generic Pattern

This Generic Pattern has the following mandatory and optional relations with adjacent Generic Services.

Service	Adjacency	Summary	Rationale
File Storage	recommended	This service offers clients the ability to store, retrieve and modify data in loosely structured form.	Every Data Management pattern must store its data at a lower data level, which means it requires the use of a File Storage service. Even in commercial products that request access to Raw Storage this is true, as these products actually provide the File Storage functionality themselves.
Authentication & Authorization	optional	This service can validate an identity claim, and it can validate the permissions required for an action, as part of an Authentication & Authorization process.	A suitable source for identity and permission information may be required for controlling access to the data stored in the Data Management facility; management of the data; managing the behaviour of the Data Management facility itself, using the Controlling functionality.
Data Protection Management	optional	This service provides the ability to protect data against accidental or wilful corruption.	The data being handled by this Pattern may need to be protected against data corruption and/or loss. Even though this might be delegated to the lower level of the File Storage service that the Pattern uses, it's usually much better to handle data protection at the logical level of this Pattern, as at this level the interdependencies of parts of the datasets is known and controllable.
Archive Management	optional	This service provides the ability to create and use archives.	The Pattern may need to archive (parts of) a structured data set, and/or may require access to an archive containing (parts of) a structured data set, in order to fulfil requests from its clients; furthermore, it may be necessary to migrate (parts of) an active structured data set to an archive. For any of this, the Data Management pattern needs access to an Archive Management service.

Applied Patterns based on this Generic Pattern

The following Applied Patterns are based wholly or in part on this Generic Pattern: