Kommentare fuer The Data Warehouse Blog http://dwhblog.org/blog A Real World Experience Fri, 30 Jul 2010 01:28:32 +0000 http://wordpress.org/?v=2.0.2 Kommentar zu DWH Modeling Rule #1: Most aggregations have to be done in the Data Warehouse directly von Frank Backes http://dwhblog.org/blog/index.php/2006/11/08/dwh-rule-1-most-aggregations-have-to-be-done-in-the-data-warehouse-directly/#comment-63107 Mon, 19 Apr 2010 07:13:42 +0000 http://dwhblog.org/blog/index.php/2006/11/08/dwh-rule-1-most-aggregations-have-to-be-done-in-the-data-warehouse-directly/#comment-63107 Kuldeep, in general there would be no differences in the generic data model for very large databases. The most important thing I recommend to cope with large data volumes is partitioning. If you apply a smart partitioning scheme to the data model and the ETL process, performance of the DWH and the Data Marts can be dramatically improved. Hope that helps Frank Kuldeep,

in general there would be no differences in the generic data model for very large databases.

The most important thing I recommend to cope with large data volumes is partitioning. If you apply a smart partitioning scheme to the data model and the ETL process, performance of the DWH and the Data Marts can be dramatically improved.

Hope that helps
Frank

]]> Kommentar zu The Enhanced Star-Schema: Part 1 - Dimension Basics von Kuldeep http://dwhblog.org/blog/index.php/2007/01/24/the-enhanced-star-schema-part-1-dimension-basics/#comment-63106 Mon, 19 Apr 2010 06:59:52 +0000 http://dwhblog.org/blog/index.php/2007/01/24/the-enhanced-star-schema-part-1-dimension-basics/#comment-63106 Can we make different dimension tables for a table having self join. Do you think instead of having self join its better to have separate dimension. Can we make different dimension tables for a table having self join. Do you think instead of having self join its better to have separate dimension.

]]> Kommentar zu DWH Modeling Rule #1: Most aggregations have to be done in the Data Warehouse directly von Kuldeep http://dwhblog.org/blog/index.php/2006/11/08/dwh-rule-1-most-aggregations-have-to-be-done-in-the-data-warehouse-directly/#comment-63105 Mon, 19 Apr 2010 06:55:43 +0000 http://dwhblog.org/blog/index.php/2006/11/08/dwh-rule-1-most-aggregations-have-to-be-done-in-the-data-warehouse-directly/#comment-63105 Nice post. it actually helps a lot. Can you post few article/tips on hierarchical data model and datawarehouse design on very large OLTP schema say 1000 GB Nice post. it actually helps a lot. Can you post few article/tips on hierarchical data model and datawarehouse design on very large OLTP schema say 1000 GB

]]> Kommentar zu Welcome to my real world experience! von Jis Thomas http://dwhblog.org/blog/index.php/2006/11/02/welcome-to-my-real-world-experience/#comment-63000 Thu, 10 Dec 2009 04:13:24 +0000 http://dwhblog.org/blog/index.php/2006/11/02/welcome-to-my-real-world-experience/#comment-63000 Really very nice to read this blog..I'm a starter in DWH.Just learned cognos tool now.I'm working in wipro Technologies.Really interesting things..I learned a lot from this blog..Thank you so much. Really very nice to read this blog..I’m a starter in DWH.Just learned cognos tool now.I’m working in wipro Technologies.Really interesting things..I learned a lot from this blog..Thank you so much.

]]> Kommentar zu The crucial question: Which BI-Tool is able to aggregate this correctly? I say: “NONE!” von Frank Backes http://dwhblog.org/blog/index.php/2006/11/25/the-crucial-question-which-bi-tool-is-able-to-aggregate-this-correctly-i-say-none/#comment-62452 Thu, 09 Apr 2009 08:49:39 +0000 http://dwhblog.org/blog/index.php/2006/11/25/the-crucial-question-which-bi-tool-is-able-to-aggregate-this-correctly-i-say-none/#comment-62452 After some time I'm not sure that MS Analysis Services would do it right. As far as I understand the "distinct sum"´function, it sums up the DISTINCT VALUES along the hierarchy and not the VALUES OF THE DISTINCT MEMBERS along the hierarchy. Consider those values please: * C1: 7.000 * C2: 7.000 * C3: 8.000 * C4: 4.000 Here are the expected results of the aggregation: * R1: 14.000 * R2: 19.000 * M1: 26.000 Can MS Analysis Services really calculate the right results? After some time I’m not sure that MS Analysis Services would do it right.

As far as I understand the “distinct sum”´function, it sums up the DISTINCT VALUES along the hierarchy and not the VALUES OF THE DISTINCT MEMBERS along the hierarchy.

Consider those values please:

* C1: 7.000
* C2: 7.000
* C3: 8.000
* C4: 4.000

Here are the expected results of the aggregation:

* R1: 14.000
* R2: 19.000
* M1: 26.000

Can MS Analysis Services really calculate the right results?

]]> Kommentar zu The Enhanced Star-Schema: Part 1 - Dimension Basics von Shahid http://dwhblog.org/blog/index.php/2007/01/24/the-enhanced-star-schema-part-1-dimension-basics/#comment-58917 Fri, 16 Jan 2009 09:12:35 +0000 http://dwhblog.org/blog/index.php/2007/01/24/the-enhanced-star-schema-part-1-dimension-basics/#comment-58917 Hi Frank, Its sounds interesting the way you are elaborating start schema and its enhancements. Regards, Shahid. Hi Frank,
Its sounds interesting the way you are elaborating start schema and its enhancements.

Regards,
Shahid.

]]> Kommentar zu Welcome to my real world experience! von Kendall Gordan, SE http://dwhblog.org/blog/index.php/2006/11/02/welcome-to-my-real-world-experience/#comment-52933 Mon, 24 Nov 2008 18:36:47 +0000 http://dwhblog.org/blog/index.php/2006/11/02/welcome-to-my-real-world-experience/#comment-52933 Don't laugh, but there are several dummies books that have real world experience, including SQL For Dummies, 6th Ed 2006, Microsoft SQL Server 2005 Express Ed For Dummies, Microsoft SQL Server 2005 Programming For Dummies Apr 2007 and my favorite Sql weekend Crash course. Kendall Gordan, SE Email: blog@foxfiresoftware.com Website: http://foxfiresoftware.com Don’t laugh, but there are several dummies books that have real world experience, including SQL For Dummies, 6th Ed 2006, Microsoft SQL Server 2005 Express Ed For Dummies, Microsoft SQL Server 2005 Programming For Dummies Apr 2007 and my favorite Sql weekend Crash course.

Kendall Gordan, SE
Email: blog@foxfiresoftware.com
Website: http://foxfiresoftware.com

]]> Kommentar zu DWH Modeling Rule #2: Build a generic, data-driven core von Kendall Gordan, SE http://dwhblog.org/blog/index.php/2006/12/19/dwh-modeling-rule-2-build-a-generic-data-driven-core/#comment-52931 Mon, 24 Nov 2008 18:30:03 +0000 http://dwhblog.org/blog/index.php/2006/12/19/dwh-modeling-rule-2-build-a-generic-data-driven-core/#comment-52931 Ah, now the star-schema posts make more sense. Kendall Gordan, SE Email: blog@foxfiresoftware.com Website: http://foxfiresoftware.com Ah, now the star-schema posts make more sense.

Kendall Gordan, SE
Email: blog@foxfiresoftware.com
Website: http://foxfiresoftware.com

]]> Kommentar zu The Enhanced Star-Schema: Part 1 - Dimension Basics von Kendall Gordan, SE http://dwhblog.org/blog/index.php/2007/01/24/the-enhanced-star-schema-part-1-dimension-basics/#comment-52929 Mon, 24 Nov 2008 18:28:21 +0000 http://dwhblog.org/blog/index.php/2007/01/24/the-enhanced-star-schema-part-1-dimension-basics/#comment-52929 I would like to hear more about bridging and surrogate keys. Kendall Gordan, SE Email: blog@foxfiresoftware.com Website: http://foxfiresoftware.com I would like to hear more about bridging and surrogate keys.

Kendall Gordan, SE
Email: blog@foxfiresoftware.com
Website: http://foxfiresoftware.com

]]> Kommentar zu DWH Managing Rule #1: The single most important prerequisite for success is a complete set of meta data von Kendall Gordan, SE http://dwhblog.org/blog/index.php/2006/11/11/dwh-managing-rule-1-the-single-most-important-prerequisite-for-success-is-a-complete-set-of-meta-data/#comment-52914 Mon, 24 Nov 2008 17:11:26 +0000 http://dwhblog.org/blog/index.php/2006/11/11/dwh-managing-rule-1-the-single-most-important-prerequisite-for-success-is-a-complete-set-of-meta-data/#comment-52914 Frank, Your attitude is simliar to ours at Foxfire. I would add indexing to your metadata as a primary importance. Website: http://foxfiresoftware.com Frank,
Your attitude is simliar to ours at Foxfire. I would add indexing to your metadata as a primary importance.

Website: http://foxfiresoftware.com

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