At the crux of many an enterprise-scale big data system stands either MapReduce or a parallel database management system. But which is more efficient? Researchers from Dublin Institute of Technology, ...

The heart of any relational database management system is the system catalog that documents the database objects and system settings being used. The system catalog offers a wealth of information about ...

A database that maintains a set of separate, related files (tables), but combines data elements from the files for queries and reports when required. The concept was developed in 1970 by Edgar Codd, ...

In the original proposal for the World Wide Web, Tim Berners-Lee wrote: A generic tool could perhaps be made to allow any database which uses a commercial DBMS to be displayed as a hypertext view. We ...

NoSQL databases arose in response to the limitations of using SQL (Structured Query Language) for database queries. NoSQL databases store and manage data in ways that enable high operational speed and ...

If you are a SQL programmer, learning recursive SQL techniques can be a boon to your productivity. A recursive query is one that refers to itself. I think the best way to quickly grasp the concept of ...

A question asked about data contained in two or more tables in a relational database. The relational query must specify the tables required and what the condition is that links them; for example, ...