Organisations often employ a number of database platforms in their information system architecture. It is not uncommon to see medium to large sized companies using three to four different RDBMS packages. Consequently the DBAs these companies look for often have to have a broad range of skills across a number of areas.
Database professionals who have worked with only one platform often wonder about learning something different as they move through their career. Some people become brave enough to spend time, money and effort to take the learning path. Others are faced with the task of learning a new system as they join a company or search for jobs. And undoubtedly recruitment specialists and employers also prefer candidates who have experience in more than one area.
From my experience I have found that when it comes to learning a new database platform, it is often best to look at what you already know and then try to find the equivalent in the new environment. This makes things much easier. Sure, there will be new concepts to understand and perhaps some un-learning to do as well, but you are not starting from scratch either. To give an example, a SQL Server developer who wants to write Oracle stored procedures may start by looking at the built-in functions and how they differ. She can also perhaps compare how variables are declared and errors are handled.
In this article I will try to provide a high-level comparison between Microsoft SQL Server and Oracle RDBMS (predominantly 10g and latter). We will mainly concentrate on the architectural concepts between the two. It is by no means an exhaustive list, but it will help you see some of the similarities and dissimilarities between the two most widely used database platforms today. Although this has been written with SQL Server DBAs in mind, it can help Oracle professionals look at the other side of the fence as well.
Without further ado, let us start exploring.
Supported Operating Systems
Microsoft SQL Server has always been a part of the Windows server family and there is little possibility that Microsoft will ever release a version for another OS. At present, SQL Server runs on XP, Vista, Windows Server 2000, 2003 and 2008. The database platform is available for both 32 bit and 64 bit versions of Windows.
For Oracle, the database software’s multi-platform support includes not only Windows (32 bit and 64 bit) but Linux and different flavours of UNIX (Solaris, HP-UX, AIX etc.) as well.
Versions and Editions
At the time of this writing, SQL Server 2008 is the current version of Microsoft’s database product. The next version due out is SQL Server 2008 R2 which is now in its CTP phase. The previous version, SQL Server 2005, saw a major upgrade from its predecessor SQL Server 2000. SQL 2005 is still comparatively new to many companies and there are still a large number of organisations using SQL Server 2000 databases.
Oracle on the other hand has come a long way since its early days and is now in version 11g R2. The more prominent version of 10g R2 has been out there in the market for some time and is considered a workhorse. 10g was the first version when Oracle introduced the concept of “grid computing”. There are companies which are still using Oracle 9i for their business applications.
In terms of editions, SQL Server 2008 R2 currently offers the following:
· Enterprise Edition: The Enterprise Edition has all the advanced features enabled and is suitable for large-scale, high volume database sites.
· Standard Edition: This offers an affordable platform for companies that do not require the advanced features of the Enterprise Edition. Most companies commonly deploy their databases in standard edition instances.
· Workgroup Edition: The Workgroup Edition is suitable for small departmental applications and incorporates core features of the product.
· Web Edition: This is meant to be used by hosting service providers as a low-cost back-end solution for web applications.
· Express Edition: A small footprint, embedded SQL Server engine that can be used for local data storage and small scale system development. The Express Edition is free to download and can be freely redistributed with a software.
· Compact Edition: The Compact Edition allows users to develop applications for Windows desktops and hand-held devices.
· Developer Edition: Every feature of the Enterprise Edition is available in the Developer Edition. However it is licensed for use by one user at a time and is meant to be used for development and testing purposes.
Apart from the Enterprise Edition, SQL Server 2008 R2 will also offer two “premium editions” for large data centres and data warehouses. These editions will be called the Datacenter Edition and the Parallel Data Warehouse Edition respectively.
For Oracle 11g R2, the flavours are:
· Enterprise Edition: This offers top performance for top money. Like the SQL Server Enterprise Edition, every feature and capability of the product is enabled in this edition.
· Standard Edition: Much like the SQL Server Standard Edition, the Oracle Standard Edition has major features of the product enabled and is suitable for most business applications.
· Standard Edition One: This edition is designed for small workgroups and licensed for minimum 5 users.
· Express Edition: This is a low footprint, small-scale, starter database for development purposes and is licensed for free redistributions. The Express Edition is still in 10g R2 version.
The table below shows the comparison between different editions of SQL Server and Oracle:
|
SQL Server 2008 R2 |
Oracle Database 11g R2 |
|
Enterprise Edition |
Enterprise Edition |
|
Standard Edition |
Standard Edition |
|
Workgroup Edition |
Standard Edition One |
|
Express edition |
Express Edition |
|
Web Edition |
X |
|
Compact Edition |
X |
|
Developer Edition |
Enterprise Edition |