Monday, December 04, 2006
DBA Job Interview Question #6: Describe the goals of Normalization
Here's question #6 in our series on DBA Job Interview Questions and this question falls under the category of "Relational Theory":
Let's talk about the basics: What is normalization?
What? You actually think I'm going to waste my typing time telling you? Google it! Seriously - that's waaaayyyy too big a topic to cover in a single blog topic.
The goals of normalization are pretty easy and you can sum it up quickly: essentially, a long time ago (30+ years ago), some very smart people realized that, if you designed a database in a certain way, it would run faster, contain less wasted space and fewer (if any) duplicate items/data. So that's the 30 second answer but it really cuts to the main goals of normalization, doesn't it? All normalization really is is a standardized approach to designing databases, right? It's sort of like a design pattern if you will.
To break down further the various Normal Forms in this blog post is just tediuos; there's tons of material out there that you can read:
Of course there are more normal forms but, from a junior-level DBA's perspective, you ONLY need to familiarize yourself with these first three. Heck - 99.9% of all DBAs out there couldn't tell you what 4th or 5th Normal Form do anyway so just focus on 1-3.
I would also suggest that you be able to go deeper if asked and be able to explain examples of using each. The wikipedia.org samples above are good about providing examples.
Hope this helps!
Technorati Tags: Scott Whigham, Whigham, SQL Server, SQL Server 2005, SQL Server, Microsoft SQL Server
Describe the goals of NormalizationThis isn't really a tough question at all and, if I'm asking this of a Junior Admin-level candidate, I don't need/expect too many details. If you understand the purpose of normalization and can throw in a few buzzwords and/or one of the forms, then I'm happy and won't ask you any further questions!
Let's talk about the basics: What is normalization?
What? You actually think I'm going to waste my typing time telling you? Google it! Seriously - that's waaaayyyy too big a topic to cover in a single blog topic.
The goals of normalization are pretty easy and you can sum it up quickly: essentially, a long time ago (30+ years ago), some very smart people realized that, if you designed a database in a certain way, it would run faster, contain less wasted space and fewer (if any) duplicate items/data. So that's the 30 second answer but it really cuts to the main goals of normalization, doesn't it? All normalization really is is a standardized approach to designing databases, right? It's sort of like a design pattern if you will.
To break down further the various Normal Forms in this blog post is just tediuos; there's tons of material out there that you can read:
Of course there are more normal forms but, from a junior-level DBA's perspective, you ONLY need to familiarize yourself with these first three. Heck - 99.9% of all DBAs out there couldn't tell you what 4th or 5th Normal Form do anyway so just focus on 1-3.
I would also suggest that you be able to go deeper if asked and be able to explain examples of using each. The wikipedia.org samples above are good about providing examples.
Hope this helps!
Technorati Tags: Scott Whigham, Whigham, SQL Server, SQL Server 2005, SQL Server, Microsoft SQL Server
