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• ADOMD.NET
• katmai
• mdx studio
• ssas
• stored procedure

• Gross margin - dense vs. sparse block evaluation mode in MDX

  Gross margin (also known as Gross profit margin or Gross profit rate) is defined as (Revenue – Cost of Sales)/Revenue. In terms of Adventure Works sample database we can write this in MDX as [Gross Margin] = ( [Measures] . [Internet Sales Amount] - [Measures] Read More... Posted Saturday, November 01, 2008 4:23 PM by mosha | 2 Comments Filed under: performance, mdx

• Optimizing order of sets in MDX crossjoins

  For scalar values a*b is the same as b*a. (although we saw that performance of these two could be different in MDX in “ Performance of multiplication in MDX ” article). But if a and b are sets, then obviously results are different – since the order of Read More... Posted Friday, October 24, 2008 1:00 AM by mosha | (Comments Off) Filed under: performance, mdx

• Optimizing MDX aggregation functions

  One of the most significant changes in Analysis Services 2008 was improving performance of MDX queries and calculations. In particular, query optimizer can choose block (a.k.a. subspace) computation mode in query plan more often than in AS2005, and usually Read More... Posted Wednesday, October 22, 2008 1:32 PM by mosha | 13 Comments Filed under: performance, mdx

• Get most out of partition slices

  Setting partition slice has always been an important optimization technique in Analysis Services. Every presentation talked about it and every whitepaper mentioned it, for example the Microsoft SQL Server 2000 Analysis Services Performance Guide contains Read More... Posted Tuesday, October 14, 2008 12:36 AM by mosha | 3 Comments Filed under: performance, mdx, ssas

• Product Volatility: Optimizing MDX with MDX Studio

  In this article we will show how to take typical, everyday MDX and optimize it by simply following advices of MDX Studio Analyzer. As a starting point, I will take “ Product Volatility ” example as published by Thomas Ivarson in his blog. It is a perfect Read More... Posted Tuesday, July 29, 2008 9:38 PM by mosha | (Comments Off) Filed under: performance, mdx, mdx studio

• MDX and partitioning

  Partitions have been a built-in feature of Analysis Services ever since the first version. Naturally, all the engine subsystems, including the MDX query optimizer, work well with partitions. There are rare cases, however, when over-aggressive prefetching Read More... Posted Tuesday, December 18, 2007 9:21 PM by mosha | 5 Comments Filed under: performance, mdx

• Optimizing Count(Filter(...)) expressions in MDX

  As the readers of my blog know, bulk evaluation mode (called "block computation mode" in Katmai) delivers much better performance in MDX than the cell-by-cell evaluation mode. Therefore the most important optimization technique with MDX in Analysis Services Read More... Posted Thursday, November 22, 2007 1:23 AM by mosha | 17 Comments Filed under: performance, mdx, katmai

• Notes about Notes from Microsoft BI Conference

  I was reading the blog post " My notes from Microsoft BI Conference " by Vidas Matelis. It is a collection of notes recorded at different presentations, chalk talks etc. I felt that I agree with some of them, disagree with some, and have no opinion about Read More... Posted Saturday, June 02, 2007 12:16 AM by mosha | 1 Comments Filed under: performance, mdx, ssas

• Best practices for server ADOMD.NET stored procedures

  In this article we will discuss some of the best practices around writing efficient Analysis Services stored procedures using server ADOMD.NET. These days there is plenty of information about writing efficient MDX - in books, whitepapers, blogs, forums Read More... Posted Thursday, April 19, 2007 12:26 AM by mosha | (Comments Off) Filed under: performance, mdx, ADOMD.NET, stored procedure

• Averages, ratios, division by zero and NON_EMPTY_BEHAVIOR

  How to get averages and other ratio based MDX calculations demonstrate great performance ? I thought I covered this subject in great depth before, but I probably wasn't concise enough. Last week I was asked to help with performance to very big and important Read More... Posted Tuesday, March 06, 2007 7:58 PM by mosha | (Comments Off) Filed under: performance, mdx

• Performance of IIF function in MDX

  IIF is one of the most popular MDX functions, (this was proved by these surveys ). Yet, it can cause significant performance degradation, which is often blamed on other parts of the system. Many times it is simple to rewrite the MDX expression to get Read More... Posted Sunday, January 28, 2007 10:20 PM by mosha | 3 Comments Filed under: performance, mdx

• Ranking in MDX

  Well, apparently I am one of the industry influencers ! At least this is what Kimball Group thinks, because they sent me their just published "The Microsoft Data Warehouse Toolkit: With SQL Server 2005 and the Microsoft Business Intelligence Toolset" Read More... Posted Tuesday, March 14, 2006 3:23 AM by mosha | 5 Comments Filed under: performance, mdx