När man kombinerar ett objektorienterat programmeringsspråk och en relationsdatabas uppstår en del problem för utvecklare eftersom objektorienterade programmeringsspråk och relationsdatabaser har olika fokus, objektorienterade programmeringsspråk fokuserar på att avbilda verkliga objekt och relationsdatabaser fokuserar på data. De problem som uppstår kallas med ett samlingsnamn för object-relational mismatch. Det finns flertalet ramverk för att hantera dessa problem. Ett av dem är Entity Framework.Syftet med detta projekt var att utvärdera hur utvecklare tycker att Entity Framework fungerar för att lösa problematiken runt object-relational mismatch, hur det är för utvecklare att lära sig använda Entity Framework samt hur tillgången på inlärningsmaterial är.Under vår studie har vi lärt oss använda Entity Framework samtidigt som vi gjort en studie av tillgången på inlärningsmaterial. Vi har också byggt om en applikation så att den använder Entity Framework. Vi har jämfört den ombyggda applikationen med den gamla applikationen för att kunna se vilken skillnad som Entity Framework bidrog till.Vi kom fram till att Entity Framework hanterar object-relational mismatch på ett bra sätt som bland annat gör att utvecklingsprocessen kortas ner då inte lika mycket kod behöver skrivas. Utvecklare med tidigare kunskaper i .NET-programmering upplever att det är lätt att lära sig Entity Framework. Att det upplevs lätt att lära sig Entity Framework hänger förmodligen ihop med att tillgången på inlärningsmaterial är god.

Context. PHP framework Laravel offers three techniques to interact with databases, Eloquent ORM, Query builder and Raw SQL. It is important to select the right database technique when developing a web application because there are pros and cons with each approach.  Objectives. In this thesis we will measure the performance of Raw SQL and Eloquent ORM, there is little research on which technique is faster. Intuitively, Raw SQL should be faster than Eloquent ORM, but exactly how much faster needs to be researched.   Methods. To measure the performance of both techniques, we developed a blog application and we ran database operations select, insert and update in both techniques.   Conclusions. Results indicated that overall Raw SQL performed better than Eloquent ORM in our database operations. There was a noticeable difference of average response time between Raw SQL and Eloquent ORM in all database operations. We can conclude that Eloquent ORM is good for building small to medium sized applications, where simple CRUD operations are used for the small amount of data. Typically for tasks like inserting a single row into a database or retrieving few rows from the database. Raw SQL is preferable for the applications that are dealing with huge amount of data, bulk data loads and complex queries.

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.

Este trabalho apresenta o desenvolvimento de um Framework de persistência que utiliza banco de dados objeto-relacional como mecanismo de persistência. Tendo por objetivo usar os conceitos de orientação a objetos descritos na norma SQL:2008, conceitos como: objeto (atributos e métodos), herança, agregação, composição, referências (REF) e estruturas multivaloradas (arrays e multiset). Para tanto se desenvolveu e formalizou (XSD) um arquivo XML que representa um esquema de objetos através da norma SQL:2008. Da mesma forma definiu-se um conjunto de anotações Java, com o intuito de facilitar a utilização e configuração do Framework, o qual é chamado de O-ODBM (Object Object-Relational Database Management). / Persistent Frameworks have been used to aid developers, managing all access to DBMS. This kind of tool maps objects from OO applications to relational databases. Besides, allow developers to persist objects without solid knowledge about DBMSs and specific languages, making better the developers productivity, mainly when different DBMS is used. On the other hands, since 1999 the SQL specification has introduced new features to manipulate objects in relational databases which since then has been called Object-Relational Database (ORDB). At present, many DBMS offer resources to manipulate objects in database, but the most of the application developers just map class to relations tables, failing to exploit the strength of O-R model. The lack of the tools that aid the project of database contributes to this situation. Considering the vantages of use of the persistent frameworks and the ORDBs, this article introduces the O-ODM (Object-Object Database Mapping) a persistent framework for relational object databases.

Este trabalho apresenta o desenvolvimento de um Framework de persistência que utiliza banco de dados objeto-relacional como mecanismo de persistência. Tendo por objetivo usar os conceitos de orientação a objetos descritos na norma SQL:2008, conceitos como: objeto (atributos e métodos), herança, agregação, composição, referências (REF) e estruturas multivaloradas (arrays e multiset). Para tanto se desenvolveu e formalizou (XSD) um arquivo XML que representa um esquema de objetos através da norma SQL:2008. Da mesma forma definiu-se um conjunto de anotações Java, com o intuito de facilitar a utilização e configuração do Framework, o qual é chamado de O-ODBM (Object Object-Relational Database Management). / Persistent Frameworks have been used to aid developers, managing all access to DBMS. This kind of tool maps objects from OO applications to relational databases. Besides, allow developers to persist objects without solid knowledge about DBMSs and specific languages, making better the developers productivity, mainly when different DBMS is used. On the other hands, since 1999 the SQL specification has introduced new features to manipulate objects in relational databases which since then has been called Object-Relational Database (ORDB). At present, many DBMS offer resources to manipulate objects in database, but the most of the application developers just map class to relations tables, failing to exploit the strength of O-R model. The lack of the tools that aid the project of database contributes to this situation. Considering the vantages of use of the persistent frameworks and the ORDBs, this article introduces the O-ODM (Object-Object Database Mapping) a persistent framework for relational object databases.

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.

Esta tese apresenta a Notação Essencial para Mapeamento Objeto-Relacional (em inglês, ENORM), uma notação de propósito geral que representa os conceitos estruturais do Mapeamento Objeto-Relacional (MOR). O objetivo de ENORM é facilitar o projeto através da aplicação clara dos padrões MOR, documentação dos mapeamentos com uma notação independente de plataforma, e tornar-se um repositório para transformações dirigidas por modelos, geração parcial de código e ferramentas de engenharia round-trip. ENORM é uma notação baseada em perfil UML, projetada para representar padrões pertencentes a lógica de modelo do domínio, com objetos do domínio incorporando tanto comportamento como dados. A notação representa padrões adotados por frameworks MOR difundidos no mercado (Active Record, do Ruby; SQLAlchemy, do Python; Entity Framework, da Microsoft .net; JPA, Cayenne, and MyBatis, do Java), seguindo os princípios Não se repita e Convenção sobre Configuração. ENORM foi avaliado por experimentos controlados, comparando a modelagem de estudantes com modelos UML e relacionais separados, atingindo um número significativamente maior de objetivos na maioria dos cenários, sem ser significativamente diferente nos piores cenários experimentais. / This thesis presents the Essential Notation for Object-Relational Mapping (ENORM), a general purpose notation that represents structural concepts of Object- Relational Mapping (ORM). The goal of ENORM is to facilitate the design by the clear application of ORM patterns, document mappings with a platform independent notation, and became a repository for model-driven transformations, partial code generation, and round-trip engineering tools. ENORM is a UML profile based notation, designed to represent patterns within a domain modeling logic, with objects of the domain incorporating both behavior and data. The notation represents patterns adopted by widespread ORM frameworks in the market (Active Record, of Ruby; SQLAlchemy, of Python; Entity Framework, of Microsoft .net; JPA, Cayenne, and MyBatis, of Java), following the Don´t Repeat Yourself and Convention over Configuration principles. ENORM was evaluated by controlled experiments, comparing the modeling by students with the use of separated UML and relational models, achieving significantly more goals in the majority of the scenarios, without being significantly different in the worst experimental scenarios.

<p>The purpose of this thesis was to investigate different concepts and tools which could support the development of a middleware which persists a temporal and versioned relational data model in an enterprise environment. Further requirements for the target application was that changes to the data model had to be facilitated, so that a small change to the model would not result in changes in several files and application layers. Other requirements include permissioning and audit tracing. In the thesis the reader is presented with a comparison of a set of tools for enterprise development and object/relational mapping. One of the tools, a code generator, is chosen as a good candidate to match the requirements of the project. An implementation is presented, where the chosen tool is used. An XML-based language which is used to define a data model and to provide input data for the tool is presented. Other concepts concerning the implementation is then described in detail. Finally, the author discusses alternative solutions and future improvements.</p>

Esta tese apresenta a Notação Essencial para Mapeamento Objeto-Relacional (em inglês, ENORM), uma notação de propósito geral que representa os conceitos estruturais do Mapeamento Objeto-Relacional (MOR). O objetivo de ENORM é facilitar o projeto através da aplicação clara dos padrões MOR, documentação dos mapeamentos com uma notação independente de plataforma, e tornar-se um repositório para transformações dirigidas por modelos, geração parcial de código e ferramentas de engenharia round-trip. ENORM é uma notação baseada em perfil UML, projetada para representar padrões pertencentes a lógica de modelo do domínio, com objetos do domínio incorporando tanto comportamento como dados. A notação representa padrões adotados por frameworks MOR difundidos no mercado (Active Record, do Ruby; SQLAlchemy, do Python; Entity Framework, da Microsoft .net; JPA, Cayenne, and MyBatis, do Java), seguindo os princípios Não se repita e Convenção sobre Configuração. ENORM foi avaliado por experimentos controlados, comparando a modelagem de estudantes com modelos UML e relacionais separados, atingindo um número significativamente maior de objetivos na maioria dos cenários, sem ser significativamente diferente nos piores cenários experimentais. / This thesis presents the Essential Notation for Object-Relational Mapping (ENORM), a general purpose notation that represents structural concepts of Object- Relational Mapping (ORM). The goal of ENORM is to facilitate the design by the clear application of ORM patterns, document mappings with a platform independent notation, and became a repository for model-driven transformations, partial code generation, and round-trip engineering tools. ENORM is a UML profile based notation, designed to represent patterns within a domain modeling logic, with objects of the domain incorporating both behavior and data. The notation represents patterns adopted by widespread ORM frameworks in the market (Active Record, of Ruby; SQLAlchemy, of Python; Entity Framework, of Microsoft .net; JPA, Cayenne, and MyBatis, of Java), following the Don´t Repeat Yourself and Convention over Configuration principles. ENORM was evaluated by controlled experiments, comparing the modeling by students with the use of separated UML and relational models, achieving significantly more goals in the majority of the scenarios, without being significantly different in the worst experimental scenarios.

The aim of this study is to analyze the Django framework in terms of design patterns and architectural principles with emphasis on development of information systems. Based on a comparison of two real systems was identified basic general functionality, the systems commonly support. This analysis helped identify the strengths and weaknesses of the framework. These ensue from the application architecture and from weaknesses of some of its components. Based on these were derived requirements for library expansion and new application components. Problems that have arisen with the solution of the new application components within the specified requirements are theoretically analyzed and described their solutions with emphasis on the application of appropriate design patterns. The solution here appears the Observer design pattern in an environment different processes, access control entries (pessimistic and optimistic locking) and a database schema in an incremental approach to the development of an information system. Implemented components were used to program information system in a team, which demonstrates the overall suitability of this framework for use in the development of information systems.