NoSQL data stores are commonly schema-less, providing no means for globally defining or managing the schema. While this offers great flexibility in early stages of application development, developers soon can experience the heavy burden of dealing with increasingly heterogeneous data. This paper targets schema evolution for NoSQL data stores, the complex task of adapting and changing the implic...

The main aspect of NoSQL data stores is “shared nothing” horizontal scaling, which enables them to support a large number of simple read/write operations per second. Most of the NoSQL data stores generally do not provide strict ACID properties. The idea is that by giving up strict ACID constraints high performance and scalability can be achieved. The objective of this paper is to study and comp...

NoSQL databases offer a powerful and flexible means of querying non-relational data. However, leading NoSQL systems typically achieve high performance goals while minimizing support for traditional data management services and defying the establishment of solid formal models. In particular, the systems generally shun tools and design principles rendered conventional by the long history of RDBMS...

NoSQL databases are popular in agile software development, where a frequently changing database schema imposes challenges for the production database. In this demo, we present Darwin, a middleware for systematic, tool-based support specifically designed for NoSQL database systems. Darwin carries out schema evolution and data migration tasks. To the best of our knowledge, Darwin is the first too...

With various advancements in the field of computing, scalability, resource utilization and power savings is being given higher priorities. NoSQL database and cloud computing goes hand in hand when compared with SQL databases. The main advantage of NoSQL databases is agility. The demand for NoSQL database is growing because most of the cloud applications built , demands high availability , speed...

One of the key advances in resolving the “big-data” problem has been the emergence of an alternative database technology. Today, classic RDBMS are complemented by a rich set of alternative Data Management Systems (DMS) specially designed to handle the volume, variety, velocity and variability of Big Data collections; these DMS include NoSQL, NewSQL and Search-based systems. NewSQL is a class of...

Graph databases and NoSQL databases, two very important topics in Big Data, have gained popularity in recent years due to their unique characteristics in their horizontally scale-out capability and flexible schema or schema-free design. The recent release of OWL-DBC , an adaptor between Oracle Spatial and Graph 2 and the TrOWL reasoner [2, 1], has built a tight integration between one of the le...

Not only SQL (NoSQL) databases are becoming increasingly popular and have some interesting strengths such as scalability and flexibility. In this paper, we investigate on the use of NoSQL systems for implementing OLAP (On-Line Analytical Processing) systems. More precisely, we are interested in instantiating OLAP systems (from the conceptual level to the logical level) and instantiating an aggr...

Popular web applications like Facebook, Google Search Engine or Amazon have to face major challenges. First of all, the volume of data that has to be managed by these applications goes far beyond the limits of traditional data bases. As a reaction, a new generation of very scalable storing solutions, NoSQL data stores, has been design by the major Internet companies. Another important challenge...