Implementation Of Business Rules Research Articles

Extended Property-level k-vertex Cardinality Constraints Model for Graph Databases

Graph databases are nowadays considered the most appropriate solution for highly connected domains. Nevertheless, the lack of a fixed schema perplexes the implementation of business rules and inhibits the usage of graph database technology in practical use cases. To tackle this challenge, we study cardinality constraints in graph databases, as their focus is on the essential component of the property graph data model - relationships between entities. This paper presents an abstract cardinality constraints model for enforcing cardinality constraints in graph databases, which represent complex graph patterns. We extend our initial k-vertex cardinality constraints model to allow the representation of cardinality constraints between a node and a subgraph with given node and/or edge properties. Second, we implement the proposed model as procedures deployed in the Neo4j Graph Database Management System (GDBMS) to prevent adding new edges that violate k-vertex cardinality constraints to the graph database. Finally, we study the performance of the implemented approach on synthetic and real datasets and analyze its performance compared to the initial model. Overall, the query execution time (QET) of the procedure increases exponentially on larger datasets. Still, the added node/edge property-level evaluation does not show a significant performance effect on the edge insertion process.

Distributed Ledger Technology Review and Decentralized Applications Development Guidelines

The Distributed Ledger Technology (DLT) provides an infrastructure for developing decentralized applications with no central authority for registering, sharing, and synchronizing transactions on digital assets. In the last years, it has drawn high interest from the academic community, technology developers, and startups mostly by the advent of its most popular type, blockchain technology. In this paper, we provide a comprehensive overview of DLT analyzing the challenges, provided solutions or alternatives, and their usage for developing decentralized applications. We define a three-tier based architecture for DLT applications to systematically classify the technology solutions described in over 100 papers and startup initiatives. Protocol and Network Tier contains solutions for digital assets registration, transactions, data structure, and privacy and business rules implementation and the creation of peer-to-peer networks, ledger replication, and consensus-based state validation. Scalability and Interoperability Tier solutions address the scalability and interoperability issues with a focus on blockchain technology, where they manifest most often, slowing down its large-scale adoption. The paper closes with a discussion on challenges and opportunities for developing decentralized applications by providing a multi-step guideline for decentralizing the design and implementation of traditional systems.

Applying k-vertex cardinality constraints on a Neo4j graph database

As with any other database solution, graph databases also need to be able to implement business rules related to a given application domain. At the moment, aside from integrity constraints, there is a limited number of mechanisms for business rules implementation in Graph Database Management Systems (GDBMSs). The underlying property graph data model does not include any formal notation on how to represent different constraints. Specifically, this paper discusses the problem of representing cardinality constraints in graph databases. We introduce the novel concept of k-vertex cardinality constraints, which enable us to specify the minimum and maximum number of edges between a vertex and a subgraph. We also propose an approach, which includes the representation of cardinality constraints through the property graph data model, and demonstrate its implementation through a series of stored procedures in Neo4j GDBMS. The proposed approach is then evaluated by performing experiments on synthetic and real datasets to test the influence of checking cardinality constraints on query execution times (QETs) when adding new edges. Additionally, a comparison is performed on synthetic datasets with varying outgoing vertex degrees in order to gain an insight into how increasing the vertex degree affects QETs. In general, the results obtained for each test scenario show that the implemented k-vertex cardinality constraints model does not significantly affect QETs. Also, the results indicate that the model is dependent on the order of the underlying k-vertex cardinality constraints and outgoing vertex degree in the dataset.

Application of the Ontology Axioms for the Development of OCL Constraints from PAL Constraints

Nowadays, ontologies play a central role in many computer science problems such as data modelling, data exchange, integration of heterogeneous data and models or software reuse. Yet, if many methods of ontology based conceptual data modelling have been proposed, only few attempts have been made to ontology axioms based modelling of business rules, which make an integral part of each conceptual data model. In this paper, we present the approach how ontology axioms can be used for business rules implementation. Our proposal we apply for the transformation of PAL (Protege Axiom Language) constraints (ontology axioms), which is based on KIF (Knowledge Interchange Format) and is part of KIF ontology, into OCL (Object Constraint Language) constraints, which are part of a UML class diagram. Z language is used to formalise the proposal and describe the transformation. The Axiom2OCL plug-in is created for automation of the transformation and a case study is carried out.

A Logical Approach for Implementing Dynamic Business Rules

Business Rules are operational rules based on data that business organizations follow to perform various activities. Regarding problem domains in the organization, business rules (BR) are classified into two groups: Static and Dynamic. A static business rule is a constraint (integrity) or derivation rule that applies to each individual state of the business, taken one state at a time. Dynamic Business Rules (DBR) are concerned with the invocation of actions in response to events. Although a lot of modeling languages and approaches for business rules modeling and different technologies and tools for business rules implementation have been proposed by researchers and practitioners in the past ten years, there is no consensus yet on technology standard and logical relationship between the modeling and the implementation of the proposed methods. The purpose of this paper is to implement DBR based on our proposed modeling methodology. In this study, DBR System architecture is developed using Java and Prolog+CG, a CG-based logic programming language which integrates Prolog, the manipulation of conceptual graphs, Java and object-oriented constructs. The advantages of our system are demonstrated with the case study of the Locomotive Maintenance’s Business (Rules). Keywords: Business Rules Approach, Dynamic Business Rules (DBR), Conceptual Graphs (CG), Mineau’s Approach, Prolog+CG

Formal design and implementation of constraints in software components

This paper deals with the modeling, automatic implementation and runtime verification of constraints in component-based applications. Constraints have been assuming an ever more relevant role in modeling distributed systems as long as business rules implementation, design-by-contract practice, and fault-tolerance requirements are concerned. Nevertheless, component developers are not sufficiently supported by existing tools to model and implement such features. In this paper, we propose a methodology and a set of tools that enable developers both to model component constraints and to generate automatically component skeletons that already implement such constraints. The methodology has been extended to support implementation even in case of legacy components.

Application of active query languages to the implementation of business rules

The paper deals with the problems of business rules implementation into the Web-based document man­agement system. XML document storing, retrieving, querying, and transformation methods are analyzed. Different active methods based on ECA (event–condition–action) model have been discussed. An Active XQuery language is recognized as the most promising, but it lacks implementation means. A specialized XML extension is created and corresponding interpreter is developed to implement business rules into the document management system of the project MOCURIS. The method proposed can be used to solve similar tasks.

Automatic implementation of constraints in component based applications

Component-based software architectures have become one of the predominant solutions in the software technologies scenario. As well, constraints have been assuming an ever more relevant role in modeling distributed systems as long as business rules implementation, design-by-contract practice, and fault-tolerance requirements are concerned. Nevertheless, component developers are not sufficiently supported by existing tools to implement these features. We address such a deficiency and we propose some implementation patterns to translate constraint models into source code and two automatic tools: the Component Constraint Modeler (CoCoMod) and the Component Constraint Generator (CoCoGen). CoCoMod enables designers to specify both component interfaces and constraints as visual UML models and automatically generates textual models for interfaces and constraints. CoCoGen executes the implementation patters to translate constraint models into source code. A simple case study is presented in order to show an application of the proposed approach.