Analysis Services Query Performance Top 10 Best Practices

I came across this little gem which I haven’t noticed so far. A nice summary of the 10 things you should do to optimize the UDM query performance. The best one is kept for last – scale out when you can no longer scale up. So true, if I could only convince customers to do so J

Protect UDM with Dimension Data Security

SQL Magazine published the first part of my article Protect UDM with Dimension Data Security in its July issue. This article explains the fundamentals of dimension data security. I am working on making the article available for public access (as of now, it requires subscriber-level access). The article code can be downloaded from the publisher’s website and from my website.

I am currently writing the second part (tentatively named Protect UDM with Dynamic Dimension Security) whose focus is dynamic dimension security. It will present two implementation approaches for implementing dynamic dimension security which are harvested from a real-life project: factless fact table and integrating with external security service.

Trust Relationships

If you use VS.NET deployment to deploy your SSAS project from one domain to another, you may get the following obscure error message on deploy.


The trust relationship between the primary domain and the trusted domain failed.


This may happen even if your workstation and the deploy server are on the same domain. The most likely reason for this error is that you have added Windows groups or users from the old domain as members to SSAS role definitions. To fix the error clear the role membership list.

Aggregate Rows and SP2

Back to my When (null) is not Null post, there is a undocumented breaking change in SQL Server 2005 SP2 which you should be aware of. In response to the customer demand, SP2 treats aggregate rows as detail rows.  As a result, if the report doesn’t use the Aggregate() function, the report will show all rows. For those using the Aggregate function, there will be no change.

TechEd 2007 US Memoirs

I am back from an one-week vacation to Clearwater, Florida followed by TechEd 2007 US in Orlando. Overall, nothing earth – shattering on the BI arena from TechEd 2007. Product groups are between releases so most of the content was SQL Server 2005-based with a few sneak previews of some of the good stuff to come in Katmai.


My presentation attracted a fairly large crowd. Almost 500 folks joined my presentation “Applied Microsoft Reporting Services 2005” which was scheduled for the first breakout slot after the keynote on Monday. Thank you! I’ve made the source code and slides available for download on my website. Courtesy to Marco Russo, I’ve also uploaded a couple of photos to capture the moment of glory.


Now that I can open my mouth about some of the cool features coming up in the Katmai release of Reporting Services that were officially announced, here are the most important ones:



  1. Standalone report designer – both the VS.NET Report Designer and the Report Builder will share the same full-featured designer. Note that “standalone” doesn’t mean “embeddable”. While a post-Katmai release may bring us a designer which can be hosted in a custom application this will probably not happen in Katmai. Sigh…

  2. Tablix region – The table and matrix regions unite and give a birth to a brand new region called tablix. This versatile control can handle it all. By changing a few properties, the tablix can morph itself into a table, crosstab, or list report! The tablix region will enable reports that were not possible or required hacks in the past to get around the matrix limitations, such as stacked columns in a crosstab reports, multiple subtotals, and multiple pivot columns. I wish I had this baby a year ago…

  3. RDL Object Model – The Katmai release will ship with public RDL Object Model. This is a great news for developers (myself included) that need to generate RDL programmatically.

  4. Acquisition of the Dundas RS controls – MS acquired the Dundas chart, gauge, and map for Reporting Services. This will sure spice up the report graphical experience and position MS to compete better with other report vendors.

  5. Acquisition of the Soft Artisans Office Writer technology – This will let business users embed reports in Microsoft Word and Excel documents.

  6. Many designer enhancements – HTML inline support, better designer experience, export to Word 2000-2007, etc.

I hope I haven’t missed something important. The first Katmai CTP build to include some of the new RS enhancement is due in July.


Nothing too exciting on the SSAS side of things as the main team of the next release is “don’t rock the boat”. It will focus mainly on improving the server performance, manageability, and robustness.

A Couple of Report Builder – UDM Hacks

If you target the SSRS Report Builder as an UDM client you may find the following two workarounds (aka hacks) useful. Both hacks require manually updating the SMDL definition. Alas, so much about model auto-generation L.

Multi-grain Relationships Don’t Appear

If a dimension joins a measure group at a higher grain the corresponding Report Builder role is excluded from the model. Steps to repro:

  1. Open the Adventure Works SSAS project in the BIDS cube designer and switch to the Dimension Usage tab.
  2. Note that the Date dimension joins the Sales Targets measure group at the Calendar Quarter level (not the Date level). That’s because the FactSalesQuota (the fact table Sales Targets is based on) stores the sales quotas at the quarter level in AW.
  3. Generate a report model from a data source pointing to the Adventure Works SSAS database
  4. Open the Report Builder and connect to the Adventure Works cube.
  5. From the Sales Targets folder, drag the Sales Amount Quota on the report canvas.
  6. Note that the Entities pane excludes the Date dimension.

Hack: Change the SMDL definition manually to include the dropped relationship. To do so, compare the SMDL definitions side-by-side before and after the grain was changed using a file comparison tool such as SourceSafe or ExamDiff. For example, the first missing role entry should look like the one below:

<RoleID>udm:Role_MeasureGroupDimension_Entity_MeasureGroup_RPM_Profitability_Measures_Entity_Dimension_Date_Entity_Dimension_RPM_Date</RoleID>

</RolePathItem>

</Path>

<AttributeID>udm:Attribute_Hierarchy_Date.Date</AttributeID>

</AttributeReference>

<AttributeReference>

<Path>

<RolePathItem>

 

In my case, I had to restore three entries caused by raising the grain of a dimension relationship. Once the entries have been restored manually and the model was deployed, the reports worked as expected.

Text-based Calculated Members Are No-Show

An UDM text-based calculated member comes back as empty in a Report Builder report. That’s because the Report Builder defaults the data type of the member to Float. Steps to repro:

  1. In the Adventure Works sample cube add the following calculated member:

    Create Member CurrentCube.[Measures].[Hello]
    As “Hello”,
    VISIBLE = 1;

  2. Assign the member to a measure group so it will show up in the Report Builder.
  3. Create a table report and uses the Hello member. The column comes back empty.

Hack: Overwrite the data type of the member in the auto-generated SMDL:

<Attribute ID=”udm:Attribute_Measure_Hello”>

<Name>Hello</Name>

<DataType>String</DataType>

<Nullable>true</Nullable>


</Attribute>

 

Deploy the model and observe that the text-based calculated member now does show.

Companion for MS Analysis Server

SQL Minds has released Companion for MS Analysis Server. Companion for MS Analysis Server is a product that helps with the health monitoring and performance tuning of Microsoft SSAS 2005. The product offers historical baseline, custom aggregations and their usage, meta data browsing, cube browsing, various reports on SSAS inner workings, trace information on slowest SQL, DMX, MDX and XMLA requests, processing information broken down by steps, capacity planning and forecasting, and more…

Not All Hyperlinks are Born Equal

The ASP.NET ReportViewer control has a HyperlinkTarget property which may give false expectations. You may believe that this property applies to all hyperlinks, including links to drillthrough reports. For example, you may attempt to set the HyperlinkTarget to _blank to open a drillthrough report in a new window. However, you will be disappointed to find that drillthrough reports ignore the HyperlinkTarget property completely. That’s because they require a page postback.


As it stands, the HyperlinkTarget property applies only to “regular” (Jump to URL) hyperlinks. Propagating HyperlinkTarget to drillthrough links is on the wish list for a next release. Meanwhile, if you need to open a drillthrough report in a new window, consider using a Jump To URL link that points to an ASP.NET page hosting the ReportViewer control (or reuse the same one that displays the master report). The ASP.NET page would parse the link and load the drillthrough report in the ReportViewer control. If you set the HyperlinkTarget property to _blank, the drillthrough report will open in a new window because it now launched from a regular link.

SQL Server 2005 SP2 Brings Self-upgrading Catalogs

A little known but very useful SSRS feature which debuted in SQL Server 2005 SP2 is that the SSRS Windows service automatically upgrades the report catalog (ReportServer database) if required. As I discussed in this blog, you may need to swap the report catalog for testing or troubleshooting purposes. In the past, you had to manually upgrade the catalog from a previous version using the Report Services Configuration Utility or using the rskeymgmt utility.

Starting with SQL Server 2005 SP2, when the SSRS Windows Service connects to the report catalog it runs the stored procedure to get the database version of the catalog. If the versions don’t match, SSRS Windows Service calls down to WMI to generate an upgrade script and applies it. The service executes the catalog version check every time it connects to the catalog.

My TechEd Session Scheduled

My breakout TechEd session BIN305 – Applied Microsoft SQL Server 2005 Reporting Services is scheduled for June 4 at 10:30 AM – 11:45 AM in room S320 A. That’s right – let’s talk reporting right after the keynote!

I hope to see some of you there.