Denna uppsats mäter och jämför prestanda mellan en objektorienterad databas och en relationsdatabas. Uppsatsen bygger på en utredande karaktär utifrån vår hypotes och vårt intresse att testa den.Hypotesen bygger på problematiken omkring mängden kod utvecklaren måste skriva för att kunna koppla ihop applikation med databas. En större mängd skriven kod som utvecklaren måste skriva borde göra att prestanda och svarstider blir långsammare. Därför ville vi undersöka om verktyg som medför en mindre mängd skriven kod kan förbättra prestandan och ge snabbare svarstider. Vi valde att testa vår hypotes mellan ADO. NET relationsdatabas och ADO. NET Entity Framework objektorienterade databas då ADO. NET genererar större mängd kod och Entity Framework innehåller verktyg som i sin tur genererar mindre mängd kod. För att kunna mäta och jämföra prestandan utvecklades en mindre kundapplikation kopplad med respektive ramverks databasmodell där båda använder sig av samma databas. Genom att mäta prestandan har vi kunnat jämföra de olika modellerna och då även kunnat se vilka fördelar och nackdelar respektive modell genererat. Vi har även mätt antal kodrader och diskuterat hur det påverkar kostnaden av systemutvecklingen samt underhållbarheten för applikationen. Det som framförallt framkom var att relationsdatabasen resulterade i en något snabbare prestanda mätt i millisekunder trots att antal kodrader blev fler jämfört med en objektorienterad databas. Den objektorienterade databasen resulterade i något sämre prestanda men med färre antal skrivna kodrader. Det medför att den kräver mindre underhåll i koden vid förvaltning av den nya applikationen. Det innebär även att tiden vid utveckling för den vane programmeraren minskar med cirka 50 % och därmed sjunker även utvecklingskostnaden, under förutsättning att en något långsammare prestanda kan accepteras.

This project examines how the quality of a code generator used in an Object-Relational Mapping (ORM) framework can be improved in terms of maintainability, testability and reusability by changing the design from a top-down perspective to a bottom up. The resulting generator is tested in a case study to verify that the new design is more cohesive and less coupled than an existing code generator.

Project management is used in increasing number of companies. Competition on the market requires companies to work more efficiently and approach separate orders as independent projects. Teams that work on the projects consist of employees from different departments, from subcontractors and from the client as well. Rapid development of broadband internet connection changed work methods and use of information technology. Thanks to ubiquitous internet connection software application delivery model known as Software as a Service (SaaS) is gaining on popularity. Main aim of this project is to design an information system that would support project management and allow effective team communication and collaboration.

This diploma thesis deals with the design and implementation of a framework for the database persistence layer development. This framework is easy to use while keeping the code elegance. It supports object oriented programming features such as inheritance and collections. Other features include versioning of objects and lazy loading. The object metadata are obtained through reflection provided by the .NET framework. The framework is not using any literal for identification (classes, attributes) even in object queries. Most of checks are done by compiler.

Två grundläggande paradigm inom datavetenskap är objektorienterad programmering och relationsdatabasteknik. En kombinering av applikationer gjorda i ett objektorienterat programmeringsspråk med den beständighet och funktionalitet som ges av relationsdatabaser är en möjlig vidareutveckling av ens kunskaper inom dessa områden. Kombinationen av dessa båda förutnämnda paradigm innebär åtminstone ett problem som uppkommer då en relationsdatabas lagrar data i tabeller och en objektorienterad applikation lagrar data i objekt. Detta problem kallas objekt/relations paradigmens missanpassning. På grund av detta problem så måste kopplingen mellan paradigmen skötas av ett ramverk av något slag. I vår rapport så undersöker vi två av de ramverk som behandlar kopplingen mellan paradigmen. Specifikt i våran studie kommer vi att fokusera på kvalitetsattributet användbarhet. De ramverk som vi undersöker heter Java Database Connectivity (JDBC) och Hibernate. Båda dessa verktyg är skapade för det objektorienterade programmeringsspråket Java. / Two of the fundamental paradigms within computer science are object oriented programming and relational databases. A combination of an object oriented application with the persistence and functionality provided by relational databases is a further development of one’s knowledge within these areas. The combination of the two aforementioned paradigms will yield at least one problem, which occurs because in a database data is stored in tables whereas an object oriented application stores data in objects. This problem is called the object/relational paradigm mismatch. Because of this problem the connection between the paradigms must be handled by some kind of framework. In our report we investigate two of the frameworks which handle the connection between the paradigms. Specifically in our study we will focus on the quality attribute usability of the two frameworks and conduct a comparison between these two. The frameworks we investigate are called Java Database Connectivity (JDBC) and Hibernate. Both of these tools are created for the object oriented programming language Java.

The objective of this work is to design and implement an Object-relational framework for PHP. This framework will be able to map objects to traditional relational database tables. In this work, an appropriate solution of  metadata specification is presented. These metadata describe how an object can be store in a relational database. The framework itself is able to store, load and query any object data in relational database. This object-relational framework has been designed for simple portability among various database systems.

Model View Controller (MVC) software architecture is widely spread and commonly used in application’s development. Therefore generation of data layer for the database model is able to reduce cost and time. After research on current Object Relational Mapping (ORM) tools, it was discovered that there are generating tools like Data Access Object (DAO) and Hibernate, however their usage causes problems like inefficiency and slow performance due to many connections with database and set up time. Most of these tools are trying to solve specific problems rather than generating a data layer which is an important component and the bottom layer of database centred applications. The proposed solution to the problem is an engineering approach where we have designed a tool named Generated Intelligent Data Layer (GIDL). GIDL tool generates small models which create the main data layer of the system according to the Database Model. The goal of this tool is to enable and allow software developers to work only with object without deep knowledge in SQL. The problem of transaction and commit is solved by the tool. Also filter objects are constructed for filtering the database. GIDL tool reduced the number of connections and also have a cache where to store object lists and modify them. The tool is compared under the same environment with Hibernate and showed a better performance in terms of time evaluations for the same functions. GIDL tool is beneficial for software developers, because it generates the entire data layer.

Diploma thesis deals with the contemporary object-relational mapping (ORM) technologies for Java. It briefly describes also competing technologies for persisting objects in files, object and object-relational databases. However main part of the thesis is the persistence of objects in relational databases using ORM frameworks. The work begins with studying general methods and issues, that these frameworks have to solve. Next, it chooses and deeply describes some ORM frameworks. They are later demonstrated on the demo application. In the following part there is a description of the problems I have been facing during the implementation of the persistence using these frameworks. Finally, there is an evaluation and a comparison of these frameworks.

This diploma work deals with design and implementation of the database neutral object-relational (OR) layer in C++ language over inherited database. The goal is to create the layer to encase the access to database from the application layer. Suggested layer will stem from the object-relation mapping technology, which is currently available for many object-programming language, such as C#, Java or Visual Basic. The work consists of three main parts. The forepart is focused on clearing object-relation mapping technology. It briefly overviews differences in capabilities and levels of implementation of various approaches. The next part describes significant properties of databases considered as back-ends for data storage in the project. The aim of this part is to present enough information to support database neutral design of the OR layer. The rest of the document deals with design and implementation of OR layer for the considered environment followed by the summarization of results and overall evaluational.

Relational databases are the most popular databases used by enterprise applications to store persistent data to this day. It gives a lot of flexibility and efficiency. A process called database normalization helps make sure that the database is free from redundancies and update anomalies. In a Database-First approach to software development, the database is designed first, and then an Object-Relational Mapping (ORM) tool is used to generate the programming classes (data layer) to interact with the database. Finally, the business logic code is written to interact with the data layer to persist the business data to the database. However, in modern application development, a process called Code-First approach evolved where the domain classes and the business logic that interacts with the domain classes are written first. Then an Object Relational Mapping (ORM) tool is used to generate the database from the domain classes. In this approach, since database design is not a concern, software programmers may ignore the process of database normalization altogether. To help software programmers in this process, this thesis takes the theory behind the five database normal forms (1NF - 5NF) and proposes Five Class Normal Forms (1CNF - 5CNF) that software programmers may use to normalize their domain classes. This thesis demonstrates that when the Five Class Normal Forms are applied manually to a class by a programmer, the resulting database that is generated from the Code-First approach is also normalized according to the rules of relational theory.