Relational Databases Management Systems (RDBMS) give you the ability to store large amounts of relational (tabular) records in many interlinked tables. A query language called SQL (the Structured Query Language), which is reasonably standard, is used to create tables, insert/update records, and perform complex queries on the data.

In DoC, we support two core RDBMS, one on Linux and one on Microsoft Windows 2000:

• Postgres SQL
  Postgres is an open-source freely available reimplementation of the old favourite Ingres RDBMS, which is being actively developed and extended by a large developer community, found at www.postgresql.org.
  • Here is our Introduction to Postgres
  • Here is our Q&A section about Postgres

• Microsoft SQL Server
  Microsoft's corporate RDBMS, SQL Server, is an enterprise-class relational database system with sophisticated management and analysis functionality. It is fully SQL99 (also known as SQL3) compliant.

  Technically, Microsoft's SQL Server appears to be extremely similar to the well-known Unix RDBMS, Sybase, so amazingly similar to it that we believe that Microsoft licensed Sybase and ported it to Windows.

  You can sign up for a combined IIS and MSSQL server account at www-asp.doc.ic.ac.uk/RDEweb/.

  What's the difference between SQL Server and PostgreSQL?

  At a basic level, very little. They both serve the same purpose - to store data in a relational way. However, SQL Server has better compliance with SQL99, which means that it supports more SQL commands. It has lots of extra functionality (such as data analysis tools and tools for moving and converting data) that PostgreSQL lacks - this is by far the most common reason to choose SQL Server over PostgreSQL. SQL Server also has a more advanced query optimizer than the 'free' version of PostgreSQL (as used in the Department) - but this is offset by the fact that the departmental PostgreSQL server is much more powerful than the SQL Server.

  On the practical side, although - as you'll see in individual guides mentioned above - we've tried quite hard to allow you to access both RDMBS from multiple programming languages on both Linux and Windows, there may be practical advantages to accessing SQL Server from other Microsoft software, eg. our IIS webserver www-asp rather than crossing platforms.

  What about other systems like Oracle or MySQL?

  We no longer support Oracle as it is not required for teaching purposes, and we recommend that you do not use it in DoC. Neither do we have MySQL. As stated above, we recommend and support PostgreSQL and Microsoft SQL Server.

  While Oracle is a very powerful fully fledged RDBMS, more powerful than Postgres and as good or better than Microsoft SQL Server, we have found it very complex to administer in the past. As a result, we have chosen to focus on Postgres and Microsoft SQL Server.

  When it comes to MySQL, our view is that there is nothing that MySQL can do that PostgreSQL doesn't do. MySQL is a less robust and less complete RDBMS, offering inadequate multi-user capabilities. The main reason people ask for MySQL is that it is simple to install and configure for a single user, so many e-commerce books use it as the backend of choice.

  Information about Java, JDBC and Databases

  © CSG / 2008