Database Journal
MS SQL Oracle DB2 Access MySQL PostgreSQL Sybase PHP SQL Etc SQL Scripts & Samples Links Database Forum

» Database Journal Home
» Database Articles
» Database Tutorials
MS SQL
Oracle
DB2
MS Access
MySQL
» RESOURCES
Database Tools
SQL Scripts & Samples
Links
» Database Forum
» Sitemap
Free Newsletters:
DatabaseDaily  
News Via RSS Feed


follow us on Twitter
Database Journal |DBA Support |SQLCourse |SQLCourse2
 

Featured Database Articles

MS SQL

Posted Nov 18, 2009

Cube Storage: Planning Partitions (Business Intelligence Development Studio Perspective) - Page 7

By William Pearson

Proactive Caching Settings

As we have noted in other articles within this series, when we use MOLAP or HOLAP storage, the data in the affected cube becomes stale the second the relational data source changes.  Proactive Caching is a feature in Analysis Services that allows us to specify when to process a measure group partition or a dimension as the data in the relational data source changes.  When Proactive Caching is implemented, Analysis Services handles maintaining updates on its own, based upon parameters we specify.  A common scenario for Proactive Caching would include a situation where we have a measure group partition where the latest data is added periodically, and then at some point the partition is merged with an existing partition.  The data for our partition is often determined based upon a transaction date.  For instance, we might want the partition updated hourly during the day with new transactions, and then at night we might merge the contents of the partition into a partition for the current week.  This approach would enable us to process the partition often, keeping it synchronized often with the relational data source, while also minimizing the amount of data that needs to be processed each cycle. 

Because Proactive Caching is established at the partition level, the need to provide this update capability is a partition planning criterion. We might, for example, choose to provide a partition for the data of the current year, wherein we might implement Proactive Caching, while we might create a partition, sans Proactive Caching, for historical data.

We can access Proactive Caching settings within the Business Intelligence Development Studio through any of the following means:

  • Clicking the ellipsis button (...) for the ProactiveCaching property value of a dimension, cube, measure group, or partition in the respective Properties window of Business Intelligence Development Studio;
  • Expanding a measure group in the Partitions tab of Cube Designer and clicking Storage Settings;
  • Expanding a measure group and selecting a partition in the grid for that measure group in the Partitions tab of Cube Designer and clicking Storage Settings;
  • Expanding a measure group and selecting a partition in the grid for that measure group in the Partitions tab of Cube Designer and clicking Storage settings on the Toolbar of the Partitions tab of Cube Designer.

1.  Ensure that the Internet_Sales_2003 partition of the Internet Sales measure group is selected, once again, on the Partitions tab.

2.  Select Cube -> Storage Settings ... from the menu atop the Partitions tab, as depicted in Illustration 35.

Select Cube -> Storage Settings ... from the Menu atop the Partitions Tab
Illustration 35: Select Cube -> Storage Settings ... from the Menu atop the Partitions Tab

We return to the Partition Storage Settings – Internet_Sales_2003 dialog that we encountered in an earlier section above. As we mentioned there, we can use Settings here to specify the proactive caching, storage, and notification settings for a dimension, cube, measure group, or partition. We can set storage type through the use of the setting slider that we see by clicking the radio button labeled Standard setting, and enabling the slider with its predefined settings for storage mode and proactive caching features. The predefined settings, along with descriptions, appear in Table 1 above.

3.  Click Cancel to dismiss the dialog.

4.  Exit Business Intelligence Development Studio, when desired.

Conclusion

In this article, we continued the general exploration of cube storage that we began in Cube Storage: Introduction, this time focusing upon partitions, which we initially introduced in Cube Storage: Introduction to Partitions. We noted that this article was one of several others in this subseries that explore various concepts surrounding partitions in Analysis Services. We discussed partition planning considerations and how they are important to partition design within our business intelligence solutions.

After discussing partition planning in general in Analysis Services, we explored each of several individual resource assignment and settings considerations in planning partition design within Analysis Services. Finally, for each of the resource assignment and settings considerations we discussed, we examined a respective example resource assignment / setting within the Adventure Works sample cube, from the perspective of the Cube Designer of the Business Intelligence Development Studio, where applicable.

About the Series ...

This article is a member of the series Introduction to MSSQL Server Analysis Services. The monthly column is designed to provide hands-on application of the fundamentals of MS SQL Server Analysis Services (“Analysis Services”), with each installment progressively presenting features and techniques designed to meet specific real-world needs. For more information on the series, please see my initial article, Creating Our First Cube.

» See All Articles by Columnist William E. Pearson, III



MS SQL Archives

Comment and Contribute

 


(Maximum characters: 1200). You have characters left.

 

 




Latest Forum Threads
MS SQL Forum
Topic By Replies Updated
SQL 2005: SSIS: Error using SQL Server credentials poverty 3 August 17th, 07:43 AM
Need help changing table contents nkawtg 1 August 17th, 03:02 AM
SQL Server Memory confifuration bhosalenarayan 2 August 14th, 05:33 AM
SQL Server Primary Key and a Unique Key katty.jonh 2 July 25th, 10:36 AM