Object-relational Mapping Research Articles

Leveraging synergy between database and programming language courses

Undergraduate courses in database systems and programming languages are frequently taught without much overlap. This paper argues that there is a substantial benefit to emphasizing some areas of commonality, both old and new, between the two subjects. Examples of such cross-fertilization that may be used to enhance one or both of the courses include query language design and implementation, object-relational mapping, transactional memory, and various aspects of the recent NoSQL movement.

Comparison of the configuration and capabilities of ORM libraries for Android

The article discusses configuration and capabilities of object-relational mapping libraries for the Android operating system. It also presents previous comparisons of ORMs for mobile systems. Configuration methods and supported mappings from java to database types are described.

Executing Complexity-Increasing Queries in Relational (MySQL) and NoSQL (MongoDB and EXist) Size-Growing ISO/EN 13606 Standardized EHR Databases.

This research shows a protocol to assess the computational complexity of querying relational and non-relational (NoSQL (not only Structured Query Language)) standardized electronic health record (EHR) medical information database systems (DBMS). It uses a set of three doubling-sized databases, i.e. databases storing 5000, 10,000 and 20,000 realistic standardized EHR extracts, in three different database management systems (DBMS): relational MySQL object-relational mapping (ORM), document-based NoSQL MongoDB, and native extensible markup language (XML) NoSQL eXist.The average response times to six complexity-increasing queries were computed, and the results showed a linear behavior in the NoSQL cases. In the NoSQL field, MongoDB presents a much flatter linear slope than eXist.NoSQL systems may also be more appropriate to maintain standardized medical information systems due to the special nature of the updating policies of medical information, which should not affect the consistency and efficiency of the data stored in NoSQL databases.One limitation of this protocol is the lack of direct results of improved relational systems such as archetype relational mapping (ARM) with the same data. However, the interpolation of doubling-size database results to those presented in the literature and other published results suggests that NoSQL systems might be more appropriate in many specific scenarios and problems to be solved. For example, NoSQL may be appropriate for document-based tasks such as EHR extracts used in clinical practice, or edition and visualization, or situations where the aim is not only to query medical information, but also to restore the EHR in exactly its original form.

Metamodel of Transformations of Concepts to Support the Object-Relational Mapping

The paper considers the problem of searching for the origin of objects and/or their sources necessary to support the object-relational mapping. The solution is presented as a variant of a specialized semantic search that takes into account the possibility of transformations of conceptual constructions of the domain description while working with the system. To take into account such transformations, a metamodel of transformations of concepts is proposed, which also takes into account the transformation of the connections between them. The basic metamodel is a specialized system of applicative type, based on the combination of domain theory methods and object theory. The metamodel is created in the category of functors, which allows us to consider transformable concepts as variants of the functor-as-object construction. The choice of the basic category ensures the possibility of parametrization of the metamodel construction, which provides a set of specialized models for a given class of subject areas. Identification of the properties of basic category requires involving of difficultly formalized criteria and is cognitive in nature.

Design and Development of Timesheet Management System

Background/Objective:In recent times most of the organizations are dependent mainly on the data. The effective management of the company is dependent on effective extraction of information from the data. The tool called Timesheet Management System (TMS) has been introduced in this paper which helps in automatic calculation of the Gross Margin (GM) and Invoice generation upon the button click. This results in the organization’s growth by reducing the manual work. Project under consideration plays a critical role in timesheet management system (TMS) so it can be considered as the project centric financial tool. This tool consists of developing the huge modules which explains the entire life cycle of the project from start to end date. This paper focus on 3 tier architecture which consists of 3 layers such as Presentation, Business and Application layers. Rivest. Methods:Adi-Shamir (RSA) algorithm is employed for secure computation of Sales Gross Margin (GM);Hibernate is used for Object Relational Mapping (ORM) that helps in mapping the .NET classes to database. Use of One Time Password (OTP) provides secure access to the timesheet portal. Findings: This paper mainly concentrates on designing and implementing Sales Gross Margin (SGM) creation, Gross Margin (GM) calculation and the invoice generation. This process includes allocating of the employee to the project by the concerned project manager which helps the allocated employee’s to access the timesheet tool. Authentication of the employee’s data will be done by the Project Manager (PM). Further the computation of Sales Gross Margin (SGM), Gross Margin and Invoice generation is done on monthly basis or after the completion of the project by the project manager (PM). All the processed data from project manager will be authenticated from higher authorities such as Subsidiary Business Unit (SBU), Account Receivable Team (ART), and Regional Sales Head (RSH). Finally, it leads to the creation of Sales Gross Margin (SGM), calculating the Gross Margin (GM) and the invoice generation. Application: Effective design and implementation of these three modules helps in tracking the profit gain in digital manner and helps in improving the profit gain. The TMS has a user friendly interface and helps to reduce the manual work in case of financial calculations. It can be improved further if the updated Cost to Company (CTC)is considered for calculating the Gross Margin. Keywords: Account Receivable Team, (ART), Gross Margin (GM), Invoice Generation, Sales Gross Margin (SGM), Subsidiary Business Unit (SBU),Timesheet Management System (TMS)

An object triple mapping system supporting detached objects: A performance and memory usage empirical comparison

The development and use of ontologies in creating more intelligent and effective applications have increased in recent years. This rise in popularity is due to the potential of ontologies in providing semantics for the data consumed by machines, allowing them to reason on these data. Providing sophisticated tools that improve the development of applications based on RDF and OWL can further accelerate the adoption of the Semantic Web. In this context, some types of ontology tools have been proposed, for instance, ontology editors, ontology reasoners, triple store tools, RDF frameworks and object triple mapping (OTM) systems. In particular, OTM systems (e.g., AliBaba, KOMMA, JOINT and so on) are of utmost importance for developing ontology-based applications through the object-oriented paradigm. They map RDF triples into data objects, enabling developers to handle RDF triples as objects in object-oriented applications. In a similar way, developers of relational database applications have been using object-relational mapping (ORM) systems, for example Hibernate, to map relational databases into objects as well as to manage the object states. The main object state that Hibernate provides is the detached one; however, except for Empire, current OTM systems do not provide detached objects. The great difference between these two types of objects is that the former one has its life cycle independent of the underlying database connection, while the latter one is bound to the connection. In this way, this paper presents an object triple mapping system that supports detached objects, named JOINT-Detached (JOINT-DE). By using JOINT-DE, developers of ontology-based applications can (i) use the objects coming from the triple store as objects of the business model, (ii) use such objects as data transfer objects (DTOs) between subsystems, and (iii) use of less resources (triple store connections) to load object properties. To evaluate the proposed tool, we first describe how we conducted an experiment to empirically compare our tool with another OTM widely used by the community. We measure performance and memory usage regarding create, retrieve and update operations. Our results indicate that: (1) JOINT-DE has better performance results in all three operations; (2) JOINT-DE has an advantage over AliBaba with respect to the memory usage in the retrieve operation; (3) AliBaba uses less memory than JOINT-DE in the update operation; and (4) we could not find statistically significant differences between the tools regarding memory usage in the create operation. Finally, to illustrate the benefits of the proposed system, a case study of a real application is presented, outlining the architectural limitations of the application using an existing OTM in the literature, as well as showing positive results to the use of JOINT-DE.

Automated Synthesis and Dynamic Analysis of Tradeoff Spaces for Object-Relational Mapping

Producing software systems that achieve acceptable tradeoffs among multiple non-functional properties remains a significant engineering problem. We propose an approach to solving this problem that combines synthesis of spaces of design alternatives from logical specifications and dynamic analysis of each point in the resulting spaces. We hypothesize that this approach has potential to help engineers understand important tradeoffs among dynamically measurable properties of system components at meaningful scales within reach of existing synthesis tools. To test this hypothesis, we developed tools to enable, and we conducted, a set of experiments in the domain of relational databases for object-oriented data models. For each of several data models, we used our approach to empirically test the accuracy of a published suite of metrics to predict tradeoffs based on the static schema structure alone. The results show that exhaustive synthesis and analysis provides a superior view of the tradeoff spaces for such designs. This work creates a path forward toward systems that achieve significantly better tradeoffs among important system properties.

JDAS: a software development framework for multidatabases

SummaryModern software development for services computing and cloud computing software systems is no longer based on a single database but on existing multidatabases and this convergence needs new software architecture and framework design. Most current popular frameworks are not designed for multidatabases, and many practical problems in development arise. This study designs and implements a software development framework called Java data access service (JDAS) for multidatabases using the object‐oriented programming language Java. The JDAS framework solves related problems that arise when other frameworks are employed in practical software development with multidatabases by presenting and introducing design methods. JDAS consists of the modules of the database abstract, object relational mapping, connection pools management, configuration management, data access service, and inversion of control. Results and case study reveal that the JDAS framework effectively reduces development complexity and improves development efficiency of the software systems with multidatabases. Copyright © 2017 John Wiley & Sons, Ltd.

Graph databases for openEHR clinical repositories

The archetype-based approach has now been adopted by major EHR interoperability standards. Soon, due to an increase in EHR adoption, more health data will be created and frequently accessed. Previous research shows that conventional persistence mechanisms such as relational and XML databases have scalability issues when storing and querying archetype-based datasets. Accordingly, we need to explore and evaluate new persistence strategies for archetype-based EHR repositories. To address the performance issues expected to occur with the increase of data, we proposed an approach using labelled property graph databases for implementing openEHR clinical repositories. We implemented the proposed approach using Neo4j and compared it to an object relational mapping (ORM) approach using Microsoft SQL server. We evaluated both approaches over a simulation of a pregnancy home-monitoring application in terms of required storage space and query response time. The results show that the proposed approach provides a better overall performance for clinical querying.

Computer-Aided Clinical Trial Recruitment Based on Domain-Specific Language Translation: A Case Study of Retinopathy of Prematurity.

Reusing the data from healthcare information systems can effectively facilitate clinical trials (CTs). How to select candidate patients eligible for CT recruitment criteria is a central task. Related work either depends on DBA (database administrator) to convert the recruitment criteria to native SQL queries or involves the data mapping between a standard ontology/information model and individual data source schema. This paper proposes an alternative computer-aided CT recruitment paradigm, based on syntax translation between different DSLs (domain-specific languages). In this paradigm, the CT recruitment criteria are first formally represented as production rules. The referenced rule variables are all from the underlying database schema. Then the production rule is translated to an intermediate query-oriented DSL (e.g., LINQ). Finally, the intermediate DSL is directly mapped to native database queries (e.g., SQL) automated by ORM (object-relational mapping).

Identifying New Directions in Database Performance Tuning

Database performance tuning is a complex and varied active research topic. With enterprise relational database management systems still reliant on the set-based relational concepts that defined early data management products, the disparity between the object-oriented application development model and the object-relational database model, called the object-relational impedance mismatch problem, is addressed by techniques such as object-relational mapping (ORM). This, compounded with changes in the way data is produced, stored and managed can result in generally poor query performance for SQL produced by object-oriented applications and an irregular fit with cost-based optimisation algorithms, and leads to questions about the need for the relational model to better adapt to a more diverse set of queries. This paper discusses existing database performance optimisation techniques and approaches and makes the argument that current database performance tuning approaches need revisiting to support queries developed through ORM tools. This paper also introduces our current research, which includes exploring concepts such as dynamic schema redefinition; query analysis and optimisation modelling driven by machine learning; and augmentation of the cost-based optimiser model.

Finding and Evaluating the Performance Impact of Redundant Data Access for Applications that are Developed Using Object-Relational Mapping Frameworks

Developers usually leverage Object-Relational Mapping (ORM) to abstract complex database accesses for large-scale systems. However, since ORM frameworks operate at a lower-level (i.e., data access), ORM frameworks do not know how the data will be used when returned from database management systems (DBMSs). Therefore, ORM cannot provide an optimal data retrieval approach for all applications, which may result in accessing redundant data and significantly affect system performance. Although ORM frameworks provide ways to resolve redundant data problems, due to the complexity of modern systems, developers may not be able to locate such problems in the code; hence, may not proactively resolve the problems. In this paper, we propose an automated approach, which we implement as a Java framework, to locate redundant data problems. We apply our framework on one enterprise and two open source systems. We find that redundant data problems exist in 87 percent of the exercised transactions. Due to the large number of detected redundant data problems, we propose an automated approach to assess the impact and prioritize the resolution efforts. Our performance assessment result shows that by resolving the redundant data problems, the system response time for the studied systems can be improved by an average of 17 percent.

Twenty years of object-relational mapping: A survey on patterns, solutions, and their implications on application design

ContextAlmost twenty years after the first release of TopLink for Java, Object-Relational Mapping Solutions (ORMSs) are available at every popular development platform, providing useful tools for developers to deal with the impedance mismatch problem. However, no matter how ubiquitous these solutions are, this essential problem remains as challenging as ever. Different solutions, each with a particular vocabulary, are difficult to learn, and make the impedance problem looks deceptively simpler than it really is. ObjectiveThe objective of this paper is to identify, discuss, and organize the knowledge concerning ORMSs, helping designers towards making better informed decisions about designing and implementing their models, focusing at the static view of persistence mapping. MethodThis paper presents a survey with nine ORMSs, selected from the top ten development platforms in popularity. Each ORMS was assessed, by documentation review and experience, in relation to architectural and structural patterns, selected from literature, and its characteristics and implementation options, including platform specific particularities. ResultsWe found out that all studied ORMSs followed architectural and structural patterns in the literature, but often with distinct nomenclature, and some singularities. Many decisions, depending on how patterns are implemented and configured, affect how class models should be adapted, in order to create practical mappings to the database. ConclusionThis survey identified what structural patterns each ORMS followed, highlighting major structural decisions a designer must take, and its consequences, in order to turn analysis models into object oriented systems. It also offers a pattern based set of characteristics that developers can use as a baseline to make their own assessments of ORMSs.

Herramienta de Mapeo Objeto Relacional y la Productividad de la Empresa Interfaces Software Group

Software development seeks to improve business productivity through automation and the use of tools, companies engaged in software development are aimed at helping other companies in the automation and development of tools for this purpose, but often them forget their own productivity. The ORM Tools (Object Relational Mapping) have been devised for this purpose, to avoid repeating many lines of programming abstraction layer, but it is necessary to consider that each has its standard or your own language by which additional time is required to occupy them. The development of these ORM aims to provide a tool according to the needs and programming standard enterprise interfaces, making for software development, this focus on other more important aspects, such as the design of the database , user interface and business layer, forgetting almost entirely abstraction layer. Using the ORM tool was reduced development time of the test application.

Preliminary design of ECCO: Experimental control system which is cloud oriented

As the development of the Tokamak, the scale of the facility is getting bigger and bigger. It is a great challenge to design, manage and operate a control system of such big scale. So we developed a new control system software: Experimental Control System which is Cloud Oriented (ECCO).ECCO consists two parts, ECCO-SDD and ECCO-REST. ECCO-SDD is used to design, manage and describe the whole control system, configure every subsystem statically. There is a SDD editor which is a human machine interface for control system designer to design by simply drag and drop, and it can be easily extended using plug-in. The ECCO-SDD translator is used to generate different outputs. All the system design and configuration is stored in the MongoDB database using an object relational mapping dedicated designed for ECCO-SDD.ECCO-REST mainly defines a control network protocol based on HTTP RESTful service, it also implements automatic discovery using Zero-configuration (Zeroconf) networking standard. Since this protocol is based on industrial standard and transparent protocol, it is open enough and it can be easily implemented by others. ECCO-REST application is the core of ECCO-REST, it is a cross platform control software running on distributed control units just like the EPICS IOC. It can be extended by user created models. It is configured by human readable JSON file which can be generated by ECCO-SDD translator.ECCO is a self-organized and de-centralized control system software. Based on the same protocol, every part of the system can discover each other, thus the controllers which ECCO-REST application running on can constitute a cloud control system, and each controller can operate autonomously.

Mapeo de objetos a través de un motor de datos NOSQL, caso de estudio: framework para desarrollo de aplicaciones web (Mapping objects through a data motor NoSQL case study: framework for web applications development)

El presente artículo surgió como una iniciativa académica en la cual se observa que las áreas de conocimiento en el desarrollo de software bajo el paradigma de Programación Orientada a Objetos - POO está confrontado por un modelo de almacenamiento de datos de tipo relacional lo que plantea dos escenarios diferentes que los desarrolladores tratan de mitigar a través de conversiones entre tipos o utilizando herramientas intermedias como el mapeo de objetos relacional que traen ciertas ventajas y desventajas, y por lo cual, se planteo dentro del proyecto la posibilidad de utilizar un motorde almacenamiento de tipo no relacional o NoSQL. Con el diseño y desarrollo del framework para generar aplicaciones web, el usuario podrá definir los objetos que considere incluir en la aplicación, los cuales se almacenarán en el motor MongoDB, el cual, organiza los datos en forma de documentos. La estructura dinámica de estos documentos se puede utilizar en gran cantidad de proyectos, incluyendo muchos que tradicionalmente funcionarían sobre bases de datos relacionales. Con el objetivo de socializar y evaluar el trabajo realizado, se diseñaron algunos instrumentos para recopilar información de usuarios con experiencia en el sector de las bases de datos y el desarrollo de software. Como resultado se resalta que los desarrolladores de software tienen claro los conceptos de persistencia de objetos a través del mapeo objeto relacional (ORM), que el aprendizaje de estas técnicas de desarrollo de software a través de la implementación de código propio o de la utilización de API´s tiene un grado alto de complejidad y en su mayoría (un 60%) son conscientes que estas implementaciones generan un bajo rendimiento en las aplicaciones. Además, se resalta la apertura de estos a optar por otras alternativas para organizar y almacenar la información, diferentes al enfoque relacional utilizado desde hace varios años.

A Mobile Application Development Tool based on Object Relational Mapping Solution

With the rapid growth of mobile application market for smart device users, an efficient development tool for mobile application software has become important and is essential. In this study, we propose a framework of mobile application development tool using Object Relational Mapping (ORM) solution in front-end domain layer, especially for mobile database-driven application system. The experimental results indicate that the development method using the proposed approach is more efficient compared to the conventional development method.

Attitudes toward inter-hospital electronic patient record exchange: discrepancies among physicians, medical record staff, and patients

BackgroundIn this era of ubiquitous information, patient record exchange among hospitals still has technological and individual barriers including resistance to information sharing. Most research on user attitudes has been limited to one type of user or aspect. Because few analyses of attitudes toward electronic patient records (EPRs) have been conducted, understanding the attitudes among different users in multiple aspects is crucial to user acceptance. This proof-of-concept study investigated the attitudes of users toward the inter-hospital EPR exchange system implemented nationwide and focused on discrepant behavioral intentions among three user groups.MethodsThe system was designed by combining a Health Level 7-based protocol, object-relational mapping, and other medical informatics techniques to ensure interoperability in realizing patient-centered practices. After implementation, three user-specific questionnaires for physicians, medical record staff, and patients were administered, with a 70 % response rate. The instrument showed favorable convergent construct validity and internal consistency reliability. Two dependent variables were applied: the attitudes toward privacy and support. Independent variables comprised personal characteristics, work characteristics, human aspects, and technology aspects. Major statistical methods included exploratory factor analysis and general linear model.ResultsThe results from 379 respondents indicated that the patients highly agreed with privacy protection by their consent and support for EPRs, whereas the physicians remained conservative toward both. Medical record staff was ranked in the middle among the three groups. The three user groups demonstrated discrepant intentions toward privacy protection and support. Experience of computer use, level of concerns, usefulness of functions, and specifically, reason to use electronic medical records and number of outpatient visits were significantly associated with the perceptions. Overall, four categories of independent variables were associated with the mean difference in the perceptions.ConclusionsDiscrepant attitudes toward privacy and support among the three user groups are identified. Patients may require further education and communication regarding the system. Culturally fit e-Consent should be incorporated into the system to fully utilize the computing power of the Internet when also considering workload. The concern for misuse of EPRs might lead to low support among physicians. Highly readable EPR documents and managerial incentives for information exchange may improve system use.

ENORM

Despite the growing adoption of object-relational mapping frameworks, UML and its most widespread extensions do not represent these mappings in a platform independent way. Maintaining mappings scattered in the code is difficult and error prone, specially if the schema is large and serves several systems. This paper proposes ENORM, a notation that extends class models representing all the essential mappings. ENORM is platform independent, providing a meta-model based on design patterns employed by three frameworks of Java, Ruby, and Python languages. An empirical evaluation indicates that ENORM performs well in comparison to separated models.

English

Object relational mapping from relational databases has become topic to be dealt with in the recent decade. Object Relational Mapping is a layer which is responsible to bridge the gap between object-oriented programs and relational database. Lot of new Object Relational Mappers have been developed which includes forward engineering as well as reverse engineering approach for developing the object code. In this paper we are proposing the method of reverse engineering for developing object code file.