The technology of object oriented databases was introduced to system developers in the late 1980?s. Despite that it is rarely used today. This thesis introduces the concept of object oriented databases as the purposed solution to the problems that exist with the use of relational databases. The thesis points to the advantages with storing the application objects in the database without disassembling them to fit a relational data model. Based on that advantages and the cost of introducing such a rarely used technology into a project, a guideline for when to use object oriented databases and when to use relational databases is given. / anders@actk.net

This paper demonstrates object oriented geographic databases's applying. It is based on geographic information systems. It describes properties of geographical information systems and their uses in practise. There are also described main properties and methods of object oriented standards in this paper. All of them are used in geographical oriented systems. New ideas are defined, object oriented raster, object oriented vector and some methods defining storing these items in object oriented database. Proposal for a method of storing data in a geographical object-oriented database is supported by case study.

現今的物件導向資料庫績效評估存在著許多的缺失。1.針對特定的應用領域，其測試工作量模型並無法代表使用者的需求。2.針對特定的資料模型，主要在衡量資料庫設計之技巧及效能。3.測試資料庫綱目變得複雜，測試運算變得繁多，使用者欲自行建立績效評估十分不容易。為了解決以上的問題，本研究擬使用物件導向系統分析的方法作為使用者建構工作量模型的工具，經過一、工作量需求分析階段。二、工作量規則描述階段。三、績效評估的測試階段。最後發展出一個用以測試物件導向資料庫的績效評估環境。由於測試之資料庫綱目與測試運算均是從使用者之需求著手，將使得測試之工作量對使用者而言，更具一致性、代表性與正確性，測試所得之數據與使用者更具相關性。另一方面，為了驗證所提出理論的可行性，我們發展了工作量模型產生器之雛型系統，使用者只須使用視覺化的圖形符號來編輯其工作量模型，系統即會產生工作量模型之規格描述，作為建構績效評估系統之進一步應用。在物件導向資料庫的應用範圍愈來愈廣泛、資料庫之資料量日益龐大的未來，以使用者需求為導向之績效評估將會是未來績效評估之發展方向。 / Existing object-oriented database benchmarks have the following drawbacks 1.They are designed to apply to specific domains, so the workload models of theirs are unable to fully represent user requirements 2.They are designed to apply to the specific data model, and their main intentions are to measure the techniques and therefore performance of database design. 3.As the database schemes are more complex and test operations are more myriad, it will be harder and harder for users intending to implement the benchmark according to the benchmark specification. In order to resolve the above problems, this thesis tries to model user's workload with system analysis methods. After 1.workload requirement analysis phase. 2.workload requirement specification phase 3.benchmark experiment phase, we will develop a benchmark application program used to benchmark the OODBMS. Because our benchmark database schemes and operations are derived from the user requirements, the workload will be more consistent, more representative and more accurate and the result will be more meaningful to users. In order to validate the theory we propose, we develop a prototype of the workload generator. After users have finished editing their workload model with visual graphic notations, the system will output workload specifications, which will be used in the later phase. As the application domain of OODBMS are more diverse and database are more huge, the trend of benchmarks is toward user requirement driven in the future.

Knowledge intensive applications require an intelligent environment, which can perform deductions in response to user queries or events that occur inside or outside of the applications. For that, we propose a Fuzzy Petri Net (FPN) model to represent the knowledge and the behavior in an intelligent object-oriented database environment, which integrates fuzzy, active and deductive rules with database objects. By gaining intelligent behaviour, the system maintains objects to perceive dynamic occurences and user queries. Thus, objects can produce new knowledge or keep themselves in a consistent, stable, and upto-date state. The behavior of a system can be unpredictable due to the rules triggering or untriggering each other (non-termination). Intermediate and final database states may also differ according to the order of rule executions (non-confluence). In order to foresee and solve problematic behavior patterns, we employ static rule analysis on the FPN structure that provides easy checking of the termination property without requiring any extra construct. In addition, with our proposed inference algorithm, we guarantee confluent rule executions. The techniques and solutions provided in this study can be utilized in various complex systems, such as weather forecasting applications, environmental information systems, defense applications, video database applications, etc. We implement a prototype of the model for the weather forecasting of the Central Anatolia Region

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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.

本研究以使用者需求導向為設計原則，提出了建構物件與物件關聯資料庫工作量產生器的發展方式，以解決(1)一般績效評估標準規格因只針對特定應用領域，而無法周詳考慮到使用者的特定需求問題；(2)廠商所發展的工作量產生器則因為可能針對其產品的特定領域作設計與測試，而失去了公正性之問題。我們的目地就是希望能以此資料庫工作量產生器的設計方式使測試資料庫效能的工作量，對使用者而言更具一致性、代表性與正確性，如此測試之結果對使用者而言才能更具意義。 我們首先分析SQL3與ODMG標準，以此構成物件關聯與物件導向資料庫之一般化的工作量模式。然後，再著手以使用者需求導向為原則，設計工作量產生器的運作方式。最後，我們實際發展了工作量產生器的雛形系統，以讓使用者能真正依其需求建立工作量並實際作績效測試，並提供給欲建構物件與物件關聯資料庫工作量產生器的人員作參考。 / This thesis provides a method of establishing Object-Oriented and Object-Relational Database Workload Generator, and this method is designed from the perspective of the user's requirements for addressing two problems: (1) the benchmark standards are generally designed to specific domains, so they are unable think comprehensively users' special requirements. (2) the database workload generators that developed by database providers may lose justice, because they might be designed to their products' special domain. Our purpose is that hope this method can make the Workload more consistent, more representative and more accurate and the test result will be more meaningful to users. Firstly, we analyze the SQL3 and ODMG standards to compose the ORDBs' and OODBs' generalized Workload Models. Then, we design our Workload Generator form the perspective of the user's requirements. Finally, we develop the Workload Generator's prototype system, it can allow users to create Workload according to their actual requirements and really do the benchmark test, and furthermore can provide a reference resource to the people who want to develop ORDB and OODB Workload Generator.

由於網路科技的進步 ,導致系統所需的資料不再只儲存於同一地點 , 面對分散式和主從式資料庫系統的使用日益頻繁 ,再加上現今的物件導向資料庫績效評估存在著許多的缺失包括 : 1.針對特定的應用領域 2. 針對特定的資料模型 3.測試資料庫綱目變得複雜 , 運算變得繁多 4.無法真實測出使用者應用領域的效能 .為了解決以上的問題 ,本研究擬使用物件導向系統分析方法作為使用者建構工作量模型的工具 , 發展出一個使用者需求導向的物件導向資料庫績效評估工作量模式。 另一方面 , 為了驗證所提出理論的可行性 , 我們發展了工作量模型規格書產生器的雛型系統 , 使用者只須使用視覺化的圖形符號來編輯其工作量模型 , 系統即會產生工作量模型的規格描述 , 作為建構績效評估系統之進一步開發 .在網路科技與物件導向資料庫的應用範圍愈來愈廣 , 資料日益龐大與型態日益複雜的未來 , 以使用者需求為導向的績效評估將是未來物件導向資料庫的績效評估之發展方向。 / As the improving of network technology, the data of database is no more stored on the same site. So the distributed database system is more and more popular. Existing object-oriented database benchmarks have the following drawbacks:1.They are designed to the specific domains , so the workload models of theirs are unable to fully reprent user requirements . 2. They are designed to the specific data models , and their intentions are to measure the techniques and performance of database design . 3.As the database schemes are more complicated and test operations are more myriad , it will be harder and harder for users to implement the benchmark. 4.They can not really measure the performance on the specific domains of users. In order to resolve the above problems , this thesis tries to model user's requirements workload using system analysis method . Because our database benchmark schemes and operations are derived from the user's requirements , the workload will be more consistent , more representative and more accurate and the result will be useful and meaningful to user . In order to apply the model we propose , we develop the prototype of the workload specification generator . After users have finished editing their workload model with the visual graphic notations , the system will generate workload specifications which will be used in the later phase . As the application domain of OODBMS are diverse and databases are huge , the trend of benchmarks is toward user requirement orientation in the future .

The current popular, distributed, n-tiered, object-oriented application architecture pro- vokes many design debates. Designs of such applications are often divided into logical layer (or tiers) - usually user interface, business logic and domain object (or data) layer, each with their own design issues. In particular, the latter contains data that needs to be stored and retrieved from permanent storage. Decisions need to be made as to the most appropriate way of doing this - the choices are usually whether to use an object database, to communicate directly with a relational database, or to use object-relational mapping (ORM) tools to allow objects to be translated to and from their relational form. Most often, depending on the perceived profile of the application, software architects make these decisions using rules of thumb derived from particular experience or the design patterns literature. Although helpful, these rules are often highly context-dependent and are of- ten misapplied. Research into the nature and magnitude of 'design forces' in this area has resulted in a series of benchmarks, intended to allow architects to understand more clearly the implications of design decisions concerning persistence. This study provides some results to help guide the architect's decisions. The study investigated and focused on the <i.performance of object persistence and com- pared ORM tools to object databases. ORM tools provide an extra layer between the business logic layer and the data layer. This study began with the hypothesis that this extra layer and mapping that happens at that point, slows down the performance of object persistence. The aim was to investigate the influence of this extra layer against the use of object databases that remove the need for this extra mapping layer. The study also investigated the impact of certain optimisation techniques on performance. A benchmark was used to compare ORM tools to object databases. The benchmark provided criteria that were used to compare them with each other. The particular benchmark chosen for this study was OO7, widely used to comprehensively test object persistence performance. Part of the study was to investigate the OO7 benchmark in greater detail to get a clearer understanding of the OO7 benchmark code and inside workings thereof. Included in this study was a comparison of the performance of an open source object database, db4o, against a proprietary object database, Versant. These representatives of object databases were compared against one another as well as against Hibernate, a popular open source representative of the ORM stable. It is important to note that these applications were initially used in their default modes (out of the box). Later some optimisation techniques were incorporated into the study, based on feedback obtained from the application developers. There is a common perception that an extra layer as introduced by Hibernate nega- tively impacts on performance. This study showed that such a layer has minimal impact on the performance. With the use of caching and other optimisation techniques, Hibernate compared well against object databases. Versant, a proprietary object database, was faster than Hibernate and the db4o open source object database. Copyright / Dissertation (MSc)--University of Pretoria, 2010. / Computer Science / unrestricted