One of the core principles of the SAP HANA database system is the comprehensive support of distributed query facility. Supporting scale-out scenarios was one of the major design principles of the system from the very beginning. Within this paper, we first give an overview of the overall functionality with respect to data allocation, metadata caching and query routing. We then dive into some level of detail for specific topics and explain features and methods not common in traditional disk-based database systems. In summary, the paper provides a comprehensive overview of distributed query processing in SAP HANA database to achieve scalability to handle large databases and heterogeneous types of workloads.

Este trabalho apresenta uma proposta para o compartilhamento de dados entre bases de dados orientadas a objetos, em ambientes de desenvolvimento de projetos. O processo de compartilhamento e realizado através de três fases: separação, evolução e integração de dados. Esta forma de compartilhamento atua através de vínculos entre os objetos de base original com a base produto. Foram definidos seis tipos de vínculos, que são estabelecidos no processo de separação: apenas leitura, isolado, flagrante, mutuamente exclusivo, independente e on-line. Com isso, ambas as bases, respeitando as limitações impostas pelo tipo de vinculo entre as mesmas, podem evoluir separadamente e depois de um determinado tempo realizarem, se conveniente, um processo de reintegração. O processo de compartilhamento de dados tem por unidade de gerenciamento os objetos, compostos de base de dados. Os conceitos apresentados podem ser universalmente aplicados, em qualquer base de dados que efetue gerenciamento sobre a composição de seus objetos. Neste trabalho os conceitos de compartilhamento de dados são exemplificados através do modelo de dados SIRIUS. / This work presents a technique to share data stored in an object-oriented databases aimed at design environments. Three process enable the sharing of data between databases: separation, evolution and data integration. Whenever a block of data need to be shared between original and product database, it is spread among both, resulting in two block: one in the original database, and another in the receiver one, identified as the product of the sharing process. During the evolution phase of the sharing process, these blocks are not required to be kept identical. Six types of links to drive the updates were defined: read only, isolated, snapshot, mutually exclusive, independent and on-line. The original and product databases, both restricted by rules imposed by the type of links, can evolve alone. After a while they may enter into an reintegration process, which uses the composite objects as the control units. The presented concepts can be applied to any data model supporting composite objects. The SIRIUS datamodel is used to exemplify those concepts.

Non-relational database management systems address some of the limitations relational database management systems have when storing large volumes of unstructured, user generated text-based data in distributed environments. They follow different approaches through the data model they use, their ability to scale data storage over distributed servers and the programming interface they provide. An experimental approach was followed to measure the capabilities these alternative database management systems present in their approach to address the limitations of relational databases in terms of their capability to store unstructured text-based data, data warehousing capabilities, ability to scale data storage across distributed servers and the level of programming abstraction they provide. The results of the research highlighted the limitations of relational database management systems. The different database management systems do address certain limitations, but not all. Document-oriented databases provide the best results and successfully address the need to store large volumes of user generated text-based data in a distributed environment / School of Computing / M. Sc. (Computer Science)

Este trabalho apresenta uma proposta para o compartilhamento de dados entre bases de dados orientadas a objetos, em ambientes de desenvolvimento de projetos. O processo de compartilhamento e realizado através de três fases: separação, evolução e integração de dados. Esta forma de compartilhamento atua através de vínculos entre os objetos de base original com a base produto. Foram definidos seis tipos de vínculos, que são estabelecidos no processo de separação: apenas leitura, isolado, flagrante, mutuamente exclusivo, independente e on-line. Com isso, ambas as bases, respeitando as limitações impostas pelo tipo de vinculo entre as mesmas, podem evoluir separadamente e depois de um determinado tempo realizarem, se conveniente, um processo de reintegração. O processo de compartilhamento de dados tem por unidade de gerenciamento os objetos, compostos de base de dados. Os conceitos apresentados podem ser universalmente aplicados, em qualquer base de dados que efetue gerenciamento sobre a composição de seus objetos. Neste trabalho os conceitos de compartilhamento de dados são exemplificados através do modelo de dados SIRIUS. / This work presents a technique to share data stored in an object-oriented databases aimed at design environments. Three process enable the sharing of data between databases: separation, evolution and data integration. Whenever a block of data need to be shared between original and product database, it is spread among both, resulting in two block: one in the original database, and another in the receiver one, identified as the product of the sharing process. During the evolution phase of the sharing process, these blocks are not required to be kept identical. Six types of links to drive the updates were defined: read only, isolated, snapshot, mutually exclusive, independent and on-line. The original and product databases, both restricted by rules imposed by the type of links, can evolve alone. After a while they may enter into an reintegration process, which uses the composite objects as the control units. The presented concepts can be applied to any data model supporting composite objects. The SIRIUS datamodel is used to exemplify those concepts.

This work focuses on NoSQL databases, their use for analytical tasks and on comparison of NoSQL databases with relational and OLAP databases. The aim is to analyse the benefits of NoSQL databases and their use for analytical purposes. The first part presents the basic principles of Business Intelligence, Data Warehousing, and Big Data. The second part deals with the key features of relational and NoSQL databases. The last part of the thesis describes the properties of four basic types of NoSQL databases, analyses their advantages, disadvantages and areas of application. The end of this part in-cludes specific examples of the use of NoSQL databases, together with the reasons for the selection of those solutions.

The Internet has become a very powerful tool in improving communication, making it easier, more convenient, and faster to access or exchange information. This project takes advantage of the strengths the Internet provides by improving communication by developing a web site for a transportation company.

Desde la aparición de las primeras bases de datos distribuidas hasta los actuales sistemas de replicación modernos, la comunidad de investigación ha propuesto múltiples protocolos para administrar la distribución y replicación de datos, junto con algoritmos de control de concurrencia para manejar las transacciones en ejecución en todos los nodos del sistema. Muchos protocolos están disponibles, por tanto, cada uno con diferentes características y rendimiento, y garantizando diferentes niveles de coherencia. Para saber qué protocolo de replicación es el más adecuado, dos aspectos deben ser considerados: el nivel necesario de coherencia y aislamiento (es decir, el criterio de corrección), y las propiedades del sistema (es decir, el escenario), que determinará el rendimiento alcanzable. Con relación a los criterios de corrección, la serialización de una copia es ampliamente aceptada como el más alto nivel de corrección. Sin embargo, su definición permite diferentes interpretaciones en cuanto a la coherencia de réplicas. En esta tesis se establece una correspondencia entre los modelos de coherencia de memoria, tal como se definen en el ámbito de la memoria compartida distribuida, y los posibles niveles de coherencia de réplicas, definiendo así nuevos criterios de corrección que corresponden a las diferentes interpretaciones identificadas sobre la serialización de una copia. Una vez seleccionado el criterio de corrección, el rendimiento alcanzable por un sistema depende en gran medida del escenario, es decir, de la suma del entorno del sistema y de las aplicaciones que se ejecutan en él. Para que el administrador pueda seleccionar un protocolo de replicación apropiado, los protocolos disponibles deben conocerse plena y profundamente. Una buena descripción de cada candidato es fundamental, pero un marco común es imperativo para comparar las diferentes opciones y estimar su rendimiento en un escenario dado. Los resultados presentados en esta tesis cumplen los objetivos establecidos y constituyen una contribución al estado del arte de la replicación de bases de datos en el momento en que se iniciaron los trabajos respectivos. Estos resultados son relevantes, además, porque abren la puerta a posibles contribuciones futuras. / Ruiz Fuertes, MI. (2011). On the Consistency, Characterization, Adaptability and Integrity of Database Replication Systems [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/11800

Multidatabases are being actively researched as a relatively new area in which many aspects are not yet fully understood. This area of transaction management in multidatabase systems still has many unresolved problems. The problem areas which this dissertation addresses are classification of multidatabase systems, global concurrency control, correctness criterion in a multidatabase environment, global deadlock detection, atomic commitment and crash recovery. A core group of research addressing these problems was identified and studied. The dissertation contributes to the multidatabase transaction management topic by introducing an alternative classification method for such multiple database systems; assessing existing research into transaction management schemes and based on this assessment, proposes a transaction processing model founded on the optimal properties of transaction management identified during the course of this research. / Computing / M. Sc. (Computer Science)

Multidatabases are being actively researched as a relatively new area in which many aspects are not yet fully understood. This area of transaction management in multidatabase systems still has many unresolved problems. The problem areas which this dissertation addresses are classification of multidatabase systems, global concurrency control, correctness criterion in a multidatabase environment, global deadlock detection, atomic commitment and crash recovery. A core group of research addressing these problems was identified and studied. The dissertation contributes to the multidatabase transaction management topic by introducing an alternative classification method for such multiple database systems; assessing existing research into transaction management schemes and based on this assessment, proposes a transaction processing model founded on the optimal properties of transaction management identified during the course of this research. / Computing / M. Sc. (Computer Science)

This work deals with the design of distributed repository aimed at storing digital forensic data. The theoretical part of the thesis describes digital forensics and what is its purpose. There are also explained Big data, suitable storages, their properties, advantages and disadvantages, in this part. The main part of the thesis deals with the design and implementation of distributed storage for digital forensic data. The design is also focused in suitable indexing of stored data, and supporting new types of digital forensic data. The performance of implemented system was evaluated for chosen type of digital forensic data PCAP files.