Some of the DW and BI links

Its been longtime since i blogged. Yesterday i came across some of the links regarding the Business intelligence andData warehoussing. Since i have worked in some of the DW and BI tools, i have a flair to watch the BI market. I got the following useful links from one of the site.I thought it is worthful to share those links.
1)BI & Data Warehousing Resources - b-eye-network.com/home/

2)Claudia Imhoff’s blog - b-eye-network.com/blogs/imhoff

3) Cyril on Business Intelligence - cyrilonbi.wordpress.com/

4) DM Review - dmreview.com

5) Frank Backes' Data Warehousing blog - dwhblog.org/blog/

6) Microsoft Business Intelligence blog by Patric Husting - bimvp.com/blogs/bsm/default.aspx

7) Monash University's Business Intelligence blog - monashbi.blogspot.com/

8) Nicholas Goodman’s blog on BI - nicholasgoodman.com

9) Oracle Business Intelligence blog - oraclebi.blogspot.com

10) Ralph Kimball official website - kimballgroup.com

11) Santosh's BO Forum - santosh4bo.ffrq.com

12) SUN CEO's blog - blogs.sun.com/jonathan/

13) The Data Warehousing Institute - dw-institute.com

14)Wordpress on Business Intelligence - Oracle - oraclebizint.wordpress.com/

15) http://www.keysoft.co.in

Would like to share more experiences, So started exploring the universe..

Thanks,

Soma

Dimension Modeling

It is the type of model used by Data Warehouse Designers. It is the underlying data model used by most of the OLAP products today in the market. In this model Data is contained in two type of tables - Fact and Dimension tables.

DM - Fact Table

This contains the measurements or metrics or facts of business processes. In addition to the facts, the only other things are foreign keys for the dimension tables.

DM - Dimension Tables

It details in the dimension tables define the context of the measurements, such as who, where, how of a measure.

Dimension Attributes

These are various columns in the DIM Tables which gives additional info about the dimensional subject. This can have one or more hierarchical relationships and mostly used in report labels and query constraints.

Before building the Warehouse, decide what it is going to contain.

For Ex:

A typical Sales warehouse will have following dimensions.

Location
Time
Product

De-Normalizing the data in the OLTP tables into DIM Tables.

maverick

Hi All,

Good to meet you all after 4 days. No Change in my belief that writing a blog will always improve your confidence in many ways.

Some of the things - that a blog will improve( in my view**)

1) It will instill a habit of reading of reading other's Blog.
I have been a regular reader of other's blog. Regular in the sense - not regular to a particular blog, but regularly visiting some blogs.

Kind of blogs i will be interested.

1) Technical Blogs - where professionals share resources, tricks and tips.
2) Book reviews - Will skim through the blogs of bibiliophiles' and bibiliomaniacs' blogs to get an idea of a reader. I will compare those feelings with my feelings that i came across when i read the same book. Will evaluate their writing skills with mine and ask myself a set of questions like.
Whether i can able to write a blog like that on that particular book i read?
Can i able to use words that much effectively?
Wil it be intriguing and engrossing to the user who read my blog?
3) General Self Development blogs- where the blogger laments about the tragedy, criticize the evnets, processes. express their liking towards others' blogs.

Today's Links

1) http://pjsrandom.wordpress.com/all-about-bi-dw/
Where the blogger discussed about the first data warehousing interview question and some other links interested he is interested in. He is working in OWB i think so as he discussed about the OWB patches.

2) http://dbafyi.blogspot.com/search/label/SQL%20Server%20database
The following question is very interesting.

What does NULL mean?
The value NULL is a very tricky subject in the database world, so don't be surprised if several applicants trip up on this question. The value NULL means UNKNOWN; it does not mean '' (empty string). Assuming ANSI_NULLS are on in your SQL Server database, which they are by default, any comparison to the value NULL will yield the value NULL. You cannot compare any value with an UNKNOWN value and logically expect to get an answer. You must use the IS NULL operator instead.

My Comment to the above question : We can also use some NULL Functions like NVL, NVL2 and COALESCE to handle NULL Values.

Awaiting our Next meet. As i am going to my home town on Vacation.