The database world has more myths and legends than the court of King Arthur. The current myths tend to be less about dragons and dungeons and more about features and performance, such as:
- Oracle can't do MOLAP.
- Oracle is as easy to tune as a cathedral organ.
- DB2 only runs on mainframes.
- SQL Server doesn't scale.
- Oracle is eye-wateringly expensive.
- Access isn't a relational database.
- SQL Server cannot row lock.
Although, sometimes there is more than a hint of scandal:
- Microsoft was caught stealing secrets from Borland.
- Oracle was caught cheating at the TPC benchmarks.
- Philippe Kahn once bought Hawaiian shirts for 3,000 database conference delegates just to annoy Microsoft.
These myths tend to surface whenever database people meet - either virtually, in the news groups, or socially, in their cups.
Where do these myths originate?
Well, this is a very competitive industry and the truth is that some of them are simply made up by competitors. I know, I happen to have been there at the birth of two of those listed above. Of course, I would never suggest that this fabrication can ever be laid at the door of the CEOs involved - I'm sure that the very smooth Larry Ellison has never been personally responsible for any of these urbane myths...
Once started, these myths are perpetuated because database people are notoriously proud of, and defensive about, their database engine. They are delighted to repeat stories that denigrate the opposition, and so the myths grow.
So, do these myths have any basis is reality or are they all just dragon food? Well, one definition of a myth is "a popular belief that is false or unsupported by facts", another is "a truth disguised and distorted", and those fit pretty well with our myths. Some are provably false, other have some basis in fact. Oddly, some, like the SQL Server row locking one, were at the same time both completely true and totally misleading.
In this series of articles we are going to look at these widely-held beliefs (all of those listed above and more) and try to separate the truth from the misinformation. Unlike Sir Robert Armstrong we will try to be uneconomical with the truth.