Ontology Learning from Relational Databases: Transforming Recursive Relationships to OWL2 Components

Ontology provides a shared and reusable piece of knowledge about a specific domain, and has been applied in many fields, such as semantic Web, e-commerce and information retrieval, etc. However, building ontology by hand is a very hard and error-prone task. Learning ontology from existing resources is a good solution. Because relational database is widely used for storing data and OWL is the latest standard recommended by W3C, this paper proposes an approach of learning OWL ontology from data in relational database. Compared with existing methods, the approach can acquire ontology from relational database automatically by using a group of learning rules instead of using a middle model. In addition, it can obtain OWL ontology, including the classes, properties, properties characteristics, cardinality and instances, while none of existing methods can acquire all of them. The proposed learning rules have been proven to be correct by practice.

As cloud computing continues to evolve, organizations are finding new ways to store the massive amounts of big data that are collected. Big data storage often require greater flexibility and scalability which can be provided by incorporating NoSQL technologies. NoSQL (Not Only SQL) is quickly becoming a popular approach to store large and unstructured data. This paper looks at the various classifications of NoSQL technologies as well as many of the notable characteristics of the technologies. The authors also describe some deficiencies of using NoSQL and give some explanation to why companies are adopting the technology. The paper concludes with suggestions for future research of NoSQL technologies and a content analysis of current articles in database management is provided in the appendix. Keywords: big data, cloud computing, document databases, MongoDB, NoSQL, Not Only SQL, unstructured database INTRODUCTION Since NoSQL database technologies entered the market in 1998, these technologies have challenged the widely-accepted relational structures and database management practices supported by traditional SQL databases. Despite this trend, the perception that NoSQL seeks to eliminate the use of relational databases is a common misconception. NoSQL is best considered with the acronym NOSQL - Not Only SQL - which more accurately represents an approach that combines non-relational databases with the use of relational ones. This approach seeks to leverage both NoSQL and SQL technologies in order to balance the demands of performance, scalability, and schema flexibility with data integrity and consistency (Purdue, 2014; Penchikala, 2013). The rise of web-scale applications creates performance, scalability, and schema flexibility demands that present significant challenges for traditional SQL / relational databases. Thus, a variety of new entrants have entered the market, each seeking to address specific challenges, including (Kent, 2012): * The need to store large volumes of data about users, objects and products * The need to provide near-real-time transaction processing * The need to provide high-speed analytics on large volumes of data (big data) * The need to support flexible data schemas for evolving business environments * The need to scale applications horizontally with predictable hardware and licensing cost structures Each NoSQL solution seeks to address one or more of the above issues, often by providing alternative approaches to long-established relational database norms. Traditional relational databases were not designed to cope with the scalability and flexibility challenges facing modern applications. Older databases were not designed to take advantage of the inexpensive storage and excess processing power available today. The defining characteristics of NoSQL technologies, as well as the relative advantages and disadvantages of NoSQL, and the subsequent influence on adoption of NoSQL technologies are each the subject of a small, yet growing body of research. This paper provides a literature review of that research and proposes potential areas where future research may focus. REVIEW OF LITERATURE NoSQL database technology is a relatively recent innovation and much of the research surrounding it is of an emerging nature. For the purpose of this literature review Galileo was primarily used for identifying the articles. Articles were selected that focused directly on NoSQL database technologies (unstructured / semi-structured databases, document databases, etc.) and articles that focused on relational databases. The contrasting articles provided the researchers with the ability to compare the features that are offered with a greater degree of variability in NoSQL databases (for example, an article on SQL scalability provided a foundation for comparing newer horizontal scaling techniques used in certain NoSQL databases). …

NoSQL and relational databases have been integrated in response to the increasing demand for scalable and efficient data management in hybrid cloud environments. The differences in data structures and query processing methods between these databases present both challenges and opportunities when designing an optimized hybrid system. This study explores the integration of NoSQL and relational databases to maximize data storage, retrieval, and processing efficiency across multiple cloud systems. NoSQL databases excel in handling unstructured and semi-structured data, offering flexibility and scalability, whereas relational databases provide robust consistency and structured query capabilities. Despite the wide availability of relational databases, certain applications require the dynamic adaptability of NoSQL systems, making integration a viable solution. The research evaluates key performance parameters, including query execution speed, scalability, data consistency, and resource utilization. Cloudsim is used for simulation, allowing for an in-depth comparison between standalone and hybrid database models. Experimental results indicate that the proposed hybrid model improves query performance by 30%, reduces latency by 20%, and enhances scalability by 40% compared to using relational or NoSQL databases alone. The novelty of this approach lies in its ability to overcome the limitations of each database type by their strengths in a dynamic cloud environment. The results highlight the effectiveness of hybrid database integration in optimizing cloud-based data management while ensuring seamless operation, adaptability, and resource efficiency.

Modern large-scale information systems often use multiple database management systems, not all of which are necessarily relational. In recent years, NoSQL databases have gained acceptance in certain domains while relational databases remain de facto standard in many others. Many "legacy" information systems also use relational databases. Unlike relational database systems, NoSQL databases do not have a common data model or query language, making it difficult for users to access data in a uniform manner when using a combination of relational and NoSQL databases or simply several different NoSQL database systems. Therefore, the need for uniform data access from such a variety of data sources becomes one of the central problems for data integration. In this paper we provide an overview of the main problems, methods, and solutions for data integration between relational and NoSQL databases, as well as between different NoSQL databases. We focus mainly on the problems of structural, syntactic, and semantic heterogeneity and on proposed solutions for uniform data access, emphasizing some of the more recent proposals.

The crucial role of competent software architecture is essential in managing the challenging of big data processing for both relational and nonrelational databases. Relational databases are designed to structure data for facilitating vertical scalability, while non-relational databases excel in handling vast volumes of unstructured data for enhancing horizontal scalability. Choosing the right database paradigm is determined by the needs of the organization, yet selecting the best option may often be a challenging task. Large number of applications still use relational databases due to its benefits of reliability, flexibility, robustness, and scalability. However, with the rapid growth in web and mobile applications as well as huge amounts of complex unstructured data generated via online and offline platforms, nonrelational databases are compensating for the inefficiency of relational databases. Since selecting the right nonrelational database method for high performing applications from a plethora of possibilities is a challenging task, existing studies are still at emergent stage to compare the performance of different popular nonrelational databases. This paper introduces a novel benchmarking approach for tailoring the comparative study of nonrelational databases. To illustrate our approach, we compare two leading non-relational databases, Aerospike and MongoDB, focusing on their average transaction times to evaluate the database performance. Our comprehensive analysis reveals the strengths of each database in read and write operations for single record and bulk record batch transactions.

The main problem has been managing databases because they are continuously expanding quickly and getting more complicated in terms of volume, variety, and velocity. Currently, Relational Database Management Systems (RDMS), also known as SQL, or traditional search engines are primarily used to manage and utilize data collection. Due to their highly semantic properties and applications, relational databases have emerged as powerful and superior during the previous two decades. The handling of a high volume of data and the variability in data type and structure has become a laborious task since Big Data entered the IT industry. Relational databases are inadequate to handle such big data due to their rigid data limitations, structure, relations, and other factors. As a result, data aggregation is rendered impossible. NoSQL databases offer a practical and understandable foundation for combining massive amounts of data, structures, and interactions. Data modeling and migration are now needed in order to define the issue. There isn't yet a tool for switching from relational to no-SQL databases. For this migration, relational (SQL) database queries must be converted to NoSQL database queries. Since relational databases (RDBMS) have found it difficult to keep up with modernization, NoSQL has emerged as the most practical database. This essay aims to highlight and assess the applications of NoSQL, the notion of NoSQL data modeling, and the NoSQL database migration procedure. NoSQL, NoSQL Roadmap, Data Modeling, ETL Approach for Data Migration, Data Loading, and Data Extraction.

Keywords: ontology extraction, relational database, semantic preserved. Abstract. To solve the problems that ontology is lack of semantic information in ontology extraction, the advantages and disadvantages of methods that building ontology from database are analyzed and we find that the maximum semantic ability of ER model is ALUIN. On the base of our research, a method of extracting semantic-preserved ontology is proposed. The method is the base of ontology storage and query. The experiment shows that our algorithm can preserve the semantic meaning and has the low complexity.

Semantic and pragmatic processing in FIDO: A flexible interface for data-base operations

Schema mappings establish a correspondence between data stored in two databases, called source and target respectively. Query processing under schema mappings has been investigated extensively in the two cases where each target atom is mapped to a query over the source (called GAV, global-as-view), and where each source atom is mapped to a query over the target (called LAV, local-as-view). The general case, called GLAV, in which queries over the source are mapped to queries over the target, has attracted a lot of attention recently, especially for data exchange. However, query processing for GLAV mappings has been considered only for the basic service of query answering, and mainly in the context of conjunctive queries (CQs) in relational databases. In this paper we study query processing for GLAV mappings in a wider sense, considering not only query answering, but also query rewriting, perfectness (the property of a rewriting to compute exactly the certain answers), and query containment relative to a mapping. We deal both with the relational case, and with graph databases, where the basic querying mechanism is that of regular path queries. Query answering in GLAV can be smoothly reduced to a combination of the LAV and GAV cases, and for CQs this reduction can be exploited also for the remaining query processing tasks. In contrast, as we show, GLAV query processing for graph databases is non-trivial and requires new insights and techniques. We obtain upper bounds for answering, rewriting, and perfectness, and show decidability of relative containment.

Since most bio-medical Linked Data Sets are simply extracted from the Relational database, lots of them are lack of ontology or concept hierarchy structure for user better understanding the data sets. This problem also limited usage of bio-medical Linked Data Sets. To resolve the problem, this paper introduced a method to dynamically generate the concept hierarchy from the Linked Data Sets. Based on the hierarchical clustering algorithm, we applied Vector Space Model(VSM) and Jaccard's Coefficient(JC) to formalize the hierarchy structure after pre-processing data. We implemented our method using two Linked Data Sets: DrugBank and Diseasome from Linked Life Data and evaluated performance with the gold standard.

A database is information collection that is organized in tables so that it can easily be accessed, managed, and updated. It is the collection of tables, schemas, queries , reports, views and other objects. The data are typically organized to model in a way that supports processes requiring information, such as modelling to find a hotel with availability of rooms, thus the people can easily locate the hotels with vacancies . There are many databases commonly, relational and non relational databases. Relational databases usually work with structured data and non relational databases are work with semi structured data. In this paper, the performance evaluation of MySQL and MongoDB is performed where MySQL is an example of relational database and MongoDB is an example of non relational databases. A relational database is a data structure that allows you to connect information from different 'tables', or different types of data buckets. Non-relational database stores data without explicit and structured mechanisms to link data from different buckets to one another. This paper discuss about the performance of MongoDB and MySQL in the field of Super Market Management System. A supermarket is a large form of the traditional grocery store also a self-service shop offering a wide variety of food and household products, organized in systematic manner. It is larger and has a open selection than a traditional grocery store.

The subject of the study is the methods of intellectual analysis, namely the construction of a decision tree, associative analysis, the identification of patterns between related events based on data presented by a relational model. The purpose of the study is to analyze the features of information units and data structures, using the example of relational systems that affect the technology of knowledge extraction. Tasks: the article solves the following tasks: to consider the relational data model as the most popular and effective data structure used in intelligent information systems for data processing and storage; to analyze the operations of relational algebra, the operational component of the relational data model regarding the application of aggregate functions; to develop a general formal statement of the problem of knowledge extraction from a relational database; to consider the concept of functional associative rules; the ID3 decision tree generation algorithm focused on data processing in relational systems is analyzed. The following methods are implemented: modern view and trends in the field of data mining; features of building information systems based on relational databases, relational algebra, theory of normalization of relations; analysis of literature on the topic of research; comparative analysis. Results achieved: the relational data model is considered as the most effective data structure used in intelligent information systems for data processing and storage. A group of aggregate functions of relational databases is identified and analyzed with respect to key attributes of the relation, which makes it possible to build logical dependencies between information units of the subject area being analyzed. The task of extracting knowledge from the database is formally formulated. The concept of functional associative rules is introduced. The ID3 decision tree generation algorithm focused on data processing in relational systems is carefully analyzed. The semantic network (SN), built on the basis of the proposed approach, allows to increase the efficiency of decision support systems. Conclusions: the universal approach proposed in the article to build a relational data model of an information system for searching for associative patterns in data allows to solve a whole class of typical tasks in which objects are connected by a "many-to-many" relationship or M →N. The relational database model is proposed as a universal information structure for solving associative analysis tasks and presenting knowledge in the form of a semantic network. The examples given in the article confirm the effectiveness of the developed and considered approaches to solving the problem of data mining in the environment of relational systems. Solving the problem of identifying knowledge in data will allow to improve the quality of management decisions made.

Relational databases are valuable sources for ontology learning. Previous work showed how precise ontologies can be learned and be fruitfully exploited to solve practical problems, such as ensuring integration and interoperation of heterogeneous databases. However, a major persisting limitation of the existing approaches is the derivation of ontologies with flat structure that simply mirror the schema of the source databases. In this paper, we present the RTAXON learning method that shows how the content of the databases can be exploited to identify categorization patterns from which class hierarchies can be generated. This fully formalized method combines a classical database schema analysis with hierarchy mining in the stored data. RTAXON is one of the methods implemented in RDBToOnto, a comprehensive tool that support the transitioning process from access to the data to generation of populated ontologies.

Assets are critical working tools in any organisation; their technical nature makes them significant for the effective outcome of strategic designs in today’s fast-growing technological age; hence, proper management of AIS is important for an increase in organisational performance. Such conventional approaches as relational databases or data warehousing are not entirely suitable for dealing with the problem intricacy, size and volatility of today’s connected data. This paper focuses on the assessment of the traditional and novel perspectives of data relationship management in AIS. It also compares traditional approaches like Relational and Object-oriented databases with new/Emerging technologies like Graph databases which optimise data complexity and semantic web technologies for better integration of the data. Also, the integration of advanced computational technologies such as machine learning and artificial intelligence improves predictive analysis and data mining to promote decision-making and organisational performance. Advanced technologies, such as blockchain and cloud applications, advance asset management even more because of their enhanced security, clarity, and expansiveness in approaching relevant databases. Blockchain enhances the features of decentralised record-keeping and immutability, while cloud solutions are scalable storage and computational resources. This paper considers problems like integration, data quality, data scalability and security and also provides some recommendations for further studies to solve these problems. Through examining these developments, the wish for the paper is to contribute to the improvement of asset management as well as decisions in this sphere in the context of growing concern and popularity of technologies.

Many types of maritime incident databases have been established that allow people to learn from past incidents and develop corresponding mitigation measures. However, our investigation of multiple international and national databases shows that most existing databases only record basic information regarding incidents in a single table. Lots of useful information is not included in the database (i.e., limited extension of the database). Meanwhile, some basic information is recorded tautologically (i.e., data redundancy). In this paper, two widely used databases are taken as examples, the Global Integrated Shipping Information System and the Lloyd's List Intelligence, to explain these common problems of existing databases. To overcome these limitations and improve the efficiency of data maintenance, this paper develops a relational maritime safety management database. The entity-relationship model is first used to depict the inter-related semantic information surrounding maritime incidents, and a relational database model is subsequently formed. Microsoft Access is employed to implement the proposed database, and a database application is also designed to demonstrate the utility of the database. Our preliminary study shows that the proposed database is implementable and has potential usage for both industry and academic research.