SBVR a factoriented OMG standard Peter Bollen Department

SBVR : a fact-oriented OMG standard Peter Bollen Department of Organization and Strategy Faculty of Economics and Business Administration Maastricht University 6200 md Maastricht, the Netherlands Peter Bollen, SBVR: a fact-oriented OMG ORM 2008, 12 -14 November, p. bollen@os. unimaas. nl standard 2008 Monterrey, Mexico

Why SBVR ? OMG’s SBVR standard is defined with the aim that business people can understand models without needing IT skills. SBVR defines a structured sub-set of English vocabulary for defining business vocabularies and business rules Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 2

Theoretical foundation of SBVR is based upon fact-orientation (ORM/NIAM) and builds strongly on the foundation of ISO-terminology science standards ISO 704: 2000 and ISO 1087 -1: 2000 [3] and Linguistics underpinned with formal (first-order) logic [4]. Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 3

SBVR time-line OMG approved the SBVR in September 2005 to become a final adopted OMG specification. In March 2006 the first interim specification was issued [5]. Finally, on December 11, 2007 SBVR became an official OMG specification [6]. Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 4

Main focus In this presentation we will introduce the main building blocks of the SBVR and we will compare the definitions of a number of modeling elements to ‘familiar’ modeling concepts in ORM [7] and Cog. NIAM [8 -10]. Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 5

The fact-oriented approach structures verbalizable knowledge into the following elements : 1. Knowledge domain sentences (or fact instances). 2. Concept definitions and naming conventions for concepts used in domain sentences. 3. Fact types. 4. Fact type readings for the fact types. 5. Population state (transition) constraints for the knowledge domain. 6. Derivation rules that specify how specific sentences can be derived from other sentences. 7. Exchange rules that specify what fact instances can be inserted, updated or deleted. ® 8. Event rules that specify when a fact is derived from other facts or when (a) fact (s) must be inserted, updated or deleted. Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 6

The 5 most important aspects in the SBVR : 1. Formal (first-order predicate) logic, ® community united by a body of shared meanings, possibly having multiple user (speech) sub-communities having their own languages and specialized vocabularies, ® 3. A body of shared meanings, represented in concepts, fact types, and business rules for these sub-communities underpinned by formal logic, ® 4. A logical formulation, for capturing the semantics of a body of shared meanings, that supports multiple forms of representation and is underpinned by formal logic. ® 5. A business representation for the logical formulation of semantics using vocabularies acceptable to the (speech) Peter Bollen, SBVR: sub-community a fact-oriented OMG ORM 2008, 12 -14 November, standard 2008 Monterrey, Mexico 7

Vocabularies and Terminology Dictionaries One of the new features that has been introduced by the SBVR to the field of conceptual business modeling at large is the explicit definition of (external) vocabularies and namespaces. This allows to qualify signifiers by adding the name of the applicable context vocabulary (e. g. , car rental industry standard glossary). In SBVR the applicable context vocabularies are defined as speech communities and vocabularies Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 8

Example of Vocabularies ® ‘ Car Rental Industry Standard Glossary ® ® ® ® Definition: the vocabulary that is defined in English by the Car Rental Industry Synonym: CRISG Reference Scheme: CRISG terms CRISG Synonym: Car Rental Industry Standard Glossary Merrian-Webster Unabridged Dictionary Definition: the vocabulary that is the 2004 Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 9

Noun- and Verb Concepts An explicit modeling assumption (or axiom) in the SBVR standard is the reference to facts and terms, respectively: ‘rules are based on facts, and facts are based on terms’. This ‘mantra’, implies at least a ‘way of working’ in which (verbalized) concepts are defined, before fact type (forms) can be phrased. Therefore we need to find (a) the fact type(s) for every business rule that needs to be modeled Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 10

Noun Concepts in SBVR. In the SBVR 1. 0 specification a noun concept is defined as a ‘concept that is the meaning of a noun or noun phrase’ An object type is defined as follows: ‘noun concept that classifies things on the basis of their common properties’ Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 11

Role is defined as: ‘noun concept that corresponds to things based on their playing a part, assuming a function or being used in some situation’ An individual concept is as: ‘ a (noun) concept that corresponds to only one object [thing]’ Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico

Verb Concepts in SBVR In the SBVR 1. 0 specification ‘verb-concept’ is synonym for ‘fact type’ and is defined as follows: ‘a concept that is the meaning of a verb phrase that involves one or more noun concepts and whose instances are all actualities. ’. An example of an expression of a verb-concept or fact type expressed in SBVR-structured english is the following: rental car is stored at branch Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 13

SBVR fact type definition SBVR does not contain an ‘attribute’ fact encoding construct as is the case in most non-fact oriented modeling languages like UML and (E)ER and therefore, SBVR prevents the associated modeling anomalies, that can occur when the attribute modeling construct is applied] ‘Fact type Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 14

Fact Type Forms. A designation that represents a fact type in SBVR is demonstrated by a fact type form. A fact type form contains a fact type reading that includes place-holders. This implements ORM/Cog. NIAM’s fact type template and placeholder constructs. Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 15

Types of Business Rules in SBVR The most common way of expressing business rules in SBVR is by means of a subset of the English Language : SBVR’s structured english. An example of a rule expression in SBVR structured English is the following: each rental car is stored at at most one branch. In this example we have two designations for an object type: rental car and branch and the quantifiers: each and at most one. Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 16

Type 1: Structural (or Definitional) Business Rules In the SBVR 1. 0 specification, a structural rule is defined as: a rule that is a claim of necessity. A structural business rule statement can take one of the following forms: necesssity business rule statement, impossibility business rule statement, restricted possibility rule statement. Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 17

A necessity statement is defined : ‘. . as a structural rule statement that is expressed positively in terms of necessity rather than negatively in terms of impossibility. ’ An example of an structural business rule expressed as a necessity business rule statement in pre-fixed style is: ‘It is necessary that each rental has exactly one requested car group. ’ Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 18

Impossibility statement An example of a structural business rule expressed in a impossibility business rule statement in pre-fix style is: ‘It is impossible that the pick-up branch of a one-way rental is the return branch of that rental. ’ Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 19

Restricted possibility statement A structural business rule expressed as a pre -fix restricted possibility statement is the following: ‘It is possible that a rental is an open rental only if the rental car of the rental has been picked up. ’ Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 20

The structural business rules in SBVR are so-called alethic constraints, that are true by definition and therefore cannot be violated by the business. Our example fact type and the example business rule (see section 3. 3. 4) are expressed in SBVR using the following SBVR expressions [6, p. 316]: ‘ rental car is stored at branch Necessity: Each rental stored car is most at one branch ‘ Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 21

Type 2: Operative (or Behavioural) Business Rules. In the SBVR 1. 0 specification an operative business rule is defined as follows: ‘. . business rule that is a claim of obligation”. An operative business rule is expressed in SBVR as an operative business rule statement, that can take one of the following forms: obligation statement, prohibitive statement and restricted permissive statement. Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 22

Obligation statement An example of an operative business rule expressed in an obligation statement in an embedded style is: ‘A rental must incur a location penalty charge if the drop-off location of the rental is not the EU-Rent site of the return branch of the rental. ’ Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 23

Prohibitive statement An example of an operative business rule expressed in a prohibitive statement is: ‘A rental must not be open if a driver of the rental is a barred driver. ’ Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 24

Restrictive permissive statement An operative business rule expressed as a restrictive permissive statement is the following: ‘ It is permitted that a rental is open only if an estimated rental charge is provisionally charged to the credit card of the renter of the rental. ’ Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 25

An operative business rule is actionable, but not necessarily automatable, it can therefore be broken by people. The existence of operative business rules or deontic constraints, furthermore, allows the SBVR to document work-instructions and other rules of guidance, that have been traditionally outside the scope of traditional languages for (conceptual) business modeling. Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 26

Table 1: Rule templates in SBVR for keyword style/rule type combinations Modality Type Prefixed Style Embedded Style Definitional/Stru ctural Necessity It is necessary that It is impossible that It is possible that …always… It is obligatory that It is prohibited that It is permitted that …. must… Impossibility Restricted possibility Operative/behavi oural Obligation Prohibation Restricted permission Peter Bollen, SBVR: a fact-oriented OMG standard …never… …sometimes… …. must not… …. may… ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 27

A Methodology to Define the complete SBVR Model for an Application Subject Area 1. Classifying, Qualifying and Creating the List of Concept Definitions Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 28

Rental car VIN 09 VIN 08 VIN 03 VIN 92 Branch Maastricht Sittard Eindhoven Fuel level 7/8 Empty The initial verbalization of the example of communication in figure 1 leads (amongst others), to the following sentences: ‘The rental car VIN 09 is stored at branch Maastricht’ ‘The rental VIN 08 is stored at branch Sittard’ ‘The rental car VIN 92 has fuel level Empty’ ‘The rental car VIN 92 is stored at branch Eindhoven’ Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 29

Now we have verbalized the example of communication, we can qualify the ‘variable positions by finding the name classes and by phrasing ‘naming-convention’ facts : ‘Within the class of all rental cars of EU-rent the vehicle identification number VIN 09 identifies a specific rental car. ’ ‘Within the class of all branches of EU-rent the name Sittard identifies a specific branch. ’ Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 30

Concept Definition Rental Car vehicle owned by EU-rent and rented to its customers Synonym: car text that is the unique identifier of a particular [rental car] organization unit that operates part of EU-Rent’s car rental business [rental organization unit] that has rental responsibility identifier of a particular [branch] The relative content of the fuel tank of a [rental car] A [rental car] must have a place where it can be physically stored until it is rented to customer Vehicle identification number Rental organization unit Branch Name Fuel level Rental Car is stored at Branch Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 31

2. Deriving Uniqueness, Mandatory Role- and Value. Constraints It is impossible that a rental car is stored at more than one branch’ ‘It is impossible that a rental car has more than one fuel level’ ‘It is necessary that a rental car is stored at a branch. ’ Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 32

Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 33

3. Mapping ORM/Cog. NIAM Models onto SBVR Vocabularies rental car Definition: vehicle owned by EU-rent and rented to its customers Synonym: car vehicle identification number Concept type: role Definition: text that is the unique identifier of a particular vehicle Synonym: VIN rental car has vehicle identification number Necessity: Each rental car has exactly one vehicle identification number. rental organization unit Concept type: role Definition: organization unit that operates part of EU-Rent’s car rental business branch Definition: rental organization unit that has rental responsibility Necessity: the concept branch is included in organization units by function’ branch has name Concept type: is-property-of fact type fuel level Definition: full or 7/8 or 3/4 or 5/8 or 1/2 or 3/8 or 1/4 or 1/8 or empty rental car has fuel level Necessity: Each rental car has at most one fuel level rental car is stored at branch Necessity: Each rental car is stored at exactly one branch 34

Conclusion The SBVR standard gives us the modeling concepts to define most, if not all business rules that can be encountered within organizations. The establishment of an OMG standard for the semantic vocabulary of business rules has been a major step forward in the process of making business domain knowledge explicit and transferable. We recommend, however, to conceptually model a business domain using ORM/Cog. NIAM’s modeling methodology as a first step. Subsequently, the found list of concept definitions, fact type(s) (readings), population constraints and derivation rules can be easily mapped onto a SBVR compliant vocabulary and a compliant set of SBVR business rule statements. Peter Bollen, SBVR: a fact-oriented OMG standard ORM 2008, 12 -14 November, 2008 Monterrey, Mexico 35