The World Wide Web infrastructure together with its more than 2 billion users enables to store information at a rate that has never been achieved before. This is mainly due to the will of storing almost all end-user interactions performed on some web applications. In order to reply to scalability and availability constraints, many web companies involved in this process recently started to desig...

NoSQL (Not Only SQL) systems are becoming popular due to known advantages such as horizontal scalability and elasticity. In this paper, we study the implementation of multidimensional data warehouses with columnoriented NoSQL systems. We define mapping rules that transform the conceptual multidimensional data model to logical column-oriented models. We consider three different logical models an...

NoSQL (Not Only SQL) systems are becoming popular due to known advantages such as horizontal scalability and elasticity. In this paper, we study the implementation of data warehouses with document-oriented NoSQL systems. We propose mapping rules that transform the multidimensional data model to logical document-oriented models. We consider three different logical models and we use them to insta...

Technological capabilities of medical imaging contributes to the increasing use of image analysis in diagnostic medical systems. Medical imaging is one of the key sources of information to medical staff. Therefore, the implementation of functions associated with the medical imaging in computer systems for medical diagnosis is desirable, or even necessary. Relational databases are the dominant t...

While Model Driven Engineering is gaining more industrial interest, scalability issues when managing large models have become a major problem in current modeling frameworks. Scalable model persistence has been achieved by using NoSQL backends for model storage, but existing modeling framework APIs have not evolved accordingly, limiting NoSQL query performance benefits. In this paper we present ...

One important aspect of physical database design is the selection of a proper set of indexes for a workload. Creation of indexes in a database system is subject to storage constraints. It is also affected by the ratio of update operations in the workload. Therefore, the cost and benefit of each set of indexes should be evaluated by a proper optimization method. The large number of index sets th...

MySQL is a low cost, high performance, good reliability and open source database product, widely used in many Internet companies. For example, there are thousands of MySQL servers being used in Taobao. Although NoSQL developed very quickly in past two years, and new products emerged in endlessly, but in the actual business application of NoSQL, the requirements to developers are relatively high...

Although most NoSQL Data Stores are schema-less, information on the structural properties of the persisted data is nevertheless essential during application development. Otherwise, accessing the data becomes simply impractical. In this paper, we introduce an algorithm for schema extraction that is operating outside of the NoSQL data store. Our method is specifically targeted at semi-structured ...

Along with the progress of the cloud computing, it became necessary to deal with various and large quantity data in the distributed database environments. So, the various NoSQL databases have been proposed and put to practical use. However, as for the NoSQL databases, since it supports the distributed environment, the integrity of the database update is basically guaranteed only by the object u...