Tag Archives: Cube Processing

X-XMLA: vii. Partition Management with XMLA

image_thumb_thumb_thumbIn the 7th article of this series, I will discuss how to manage your partitions with XMLA.   We will be focused on the partition structures as opposed to partition processing which was covered in the previous post.

Creating or altering a partition

I have already discussed object creation with XMLA in part 3 of this series.  Remember that when altering the partition you need to have all of the partition definition you wish to keep as well as what you are changing in the XMLA.  If you have a subset of the definition, SSAS will assume you want to remove the missing parts.

Adding a partition to an existing measure group

One area where a partition is different from other objects is that you can add a partition to an existing measure group.  This is often done to improve processing performance or to match the underlying data architecture (especially if table partitioning is already in place for the source tables).  Often the partitions are based on date and correspond to the date the data is loaded.  For instance, you may have separate partitions for each year.  So at the beginning of the next year you need to add a partition.  In this case, you create a new partition with a specific data source definition for that partition.

If the measure group only has one partition that is based on a single table, you may need to change the source definition so you can properly add a new partition.  There are two common ways to manage the data sources to support partitions.  The first is to create views that map to the partition structure in the cube and then the data source for each partition can point directly to a particular table or view.  The second way is to specify a query definition that usually points at one table and filters the data based on one or more keys.

In either case, the XMLA is constructed as a Create command with the ParentObject specifying the measure group that the partition will be added to.  The Object definition contains the ID, Name, Source and other properties that make up the partition.  The example below shows the definition for adding a partition with that covers the month of January using a filter in the QueryDefinition for the Source.

<Create xmlns="http://schemas.microsoft.com/analysisservices/2003/engine">
    <ParentObject>
        <DatabaseID>Adventure Works DW 2008R2 SE</DatabaseID>
        <CubeID>Adventure Works DW</CubeID>
        <MeasureGroupID>Fact Internet Sales 1</MeasureGroupID>
    </ParentObject>
    <ObjectDefinition>
        <Partition xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ddl2="http://schemas.microsoft.com/analysisservices/2003/engine/2" xmlns:ddl2_2="http://schemas.microsoft.com/analysisservices/2003/engine/2/2" xmlns:ddl100_100="http://schemas.microsoft.com/analysisservices/2008/engine/100/100" xmlns:ddl200="http://schemas.microsoft.com/analysisservices/2010/engine/200" xmlns:ddl200_200="http://schemas.microsoft.com/analysisservices/2010/engine/200/200" xmlns:ddl300="http://schemas.microsoft.com/analysisservices/2011/engine/300" xmlns:ddl300_300="http://schemas.microsoft.com/analysisservices/2011/engine/300/300">
            <ID>Internet_Sales_Jan2011</ID>
            <Name>Internet_Sales_Jan2011</Name>
            <Source xsi:type="QueryBinding">
                <DataSourceID>Adventure Works DW</DataSourceID>
                <QueryDefinition>SELECT * 
                        FROM dbo.FactInternetSales 
                        WHERE OrderDateKey BETWEEN 20110101 AND 20110131</QueryDefinition>
            </Source>
            <StorageMode>Molap</StorageMode>
            <ProcessingMode>Regular</ProcessingMode>
            <ProactiveCaching>
                <SilenceInterval>-PT1S</SilenceInterval>
                <Latency>-PT1S</Latency>
                <SilenceOverrideInterval>-PT1S</SilenceOverrideInterval>
                <ForceRebuildInterval>-PT1S</ForceRebuildInterval>
                <AggregationStorage>MolapOnly</AggregationStorage>
                <Source xsi:type="ProactiveCachingInheritedBinding">
                    <NotificationTechnique>Server</NotificationTechnique>
                </Source>
            </ProactiveCaching>
            <EstimatedRows>60398</EstimatedRows>
            <AggregationDesignID>Internet Sales</AggregationDesignID>
        </Partition>
    </ObjectDefinition>
</Create>

Merging partitions

In some cases, you will find the need to merge partitions.  In our example above we added a partition for the month of January.  However, as the your partition count becomes larger there is benefit to merging partitions into historical or archive partitions.    Or you may even decide that merging will help with maintenance or processing.  In either case, the logic is fairly simple.  You have one or more source partitions being merged into target partition.  The XMLA for this is pretty straightforward.

There are a couple of nuances to be aware of including the fact that the structure and the aggregation designs need to be the same to support merging.  If you plan to merge, you should take this into account when building partitions and applying aggregation designs.  Furthermore, if you use partition slices you will likely need to modify the target’s slice after the merge is account for the new data.

Here is the code required to merge two source partitions into a target partition.  The result will be one partition.

<MergePartitions xmlns="http://schemas.microsoft.com/analysisservices/2003/engine">
  <Sources>
    <Source>
      <DatabaseID>Adventure Works DW 2008R2 SE2</DatabaseID>
      <CubeID>Adventure Works DW</CubeID>
      <MeasureGroupID>Fact Internet Sales 1</MeasureGroupID>
      <PartitionID>Internet_Sales_Jan2011</PartitionID>
    </Source>
    <Source>
        <DatabaseID>Adventure Works DW 2008R2 SE2</DatabaseID>
        <CubeID>Adventure Works DW</CubeID>
        <MeasureGroupID>Fact Internet Sales 1</MeasureGroupID>
        <PartitionID>Internet_Sales_Feb2011</PartitionID>
    </Source>
  </Sources>
  <Target>
    <DatabaseID>Adventure Works DW 2008R2 SE2</DatabaseID>
    <CubeID>Adventure Works DW</CubeID>
    <MeasureGroupID>Fact Internet Sales 1</MeasureGroupID>
    <PartitionID>Internet_Sales</PartitionID>
  </Target>
</MergePartitions>

As you can see in the example above, all that you need to specify is the full address for each partition and identify which are the sources and which one is the target.

Setting the Slice Property

Before digging into the XMLA a couple of notes on the data slice in cubes.  First, slices are not required for MOLAP partitions, however, they can help with query performance.  While in current versions of SSAS (2005 and later), the system will determine the slice based on the data, it is not always accurate.  Keep in mind that a slice does not affect processing or the source data for a partition.  That is determined by the Source attribute and related definition.

Refer to the following blog posts Jesse Orosz and Mosha Pasumanky for more information as the details around the value of assigning scope which is beyond the scope of this post:

http://jesseorosz.wordpress.com/?s=slices

http://sqlblog.com/blogs/mosha/archive/2008/10/14/get-most-out-of-partition-slices.aspx

Assuming you need to set the slice or if you need to change it due to a merge here is the XMLA to alter a partition’s slice property.

<Alter AllowCreate="true" ObjectExpansion="ObjectProperties" xmlns="http://schemas.microsoft.com/analysisservices/2003/engine">
  <Object>
    <DatabaseID>Adventure Works DW 2008R2 SE2</DatabaseID>
    <CubeID>Adventure Works DW</CubeID>
    <MeasureGroupID>Fact Internet Sales 1</MeasureGroupID>
    <PartitionID>Internet_Sales_Feb2011</PartitionID>
  </Object>
  <ObjectDefinition>
    <Partition xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ddl2="http://schemas.microsoft.com/analysisservices/2003/engine/2" xmlns:ddl2_2="http://schemas.microsoft.com/analysisservices/2003/engine/2/2" xmlns:ddl100_100="http://schemas.microsoft.com/analysisservices/2008/engine/100/100" xmlns:ddl200="http://schemas.microsoft.com/analysisservices/2010/engine/200" xmlns:ddl200_200="http://schemas.microsoft.com/analysisservices/2010/engine/200/200" xmlns:ddl300="http://schemas.microsoft.com/analysisservices/2011/engine/300" xmlns:ddl300_300="http://schemas.microsoft.com/analysisservices/2011/engine/300/300">
      <ID>Internet_Sales_Feb2011</ID>
      <Name>Internet_Sales_Feb2011</Name>
      <Source xsi:type="QueryBinding">
        <DataSourceID>Adventure Works DW</DataSourceID>
        <QueryDefinition>SELECT * 
                        FROM dbo.FactInternetSales 
                        WHERE OrderDateKey BETWEEN 20110102 AND 20110228</QueryDefinition>
      </Source>
      <StorageMode>Molap</StorageMode>
      <ProcessingMode>Regular</ProcessingMode>
      <Slice>{[Date].[Calendar].[Month].&amp;[2011]&amp;[2]}</Slice>
      <ProactiveCaching>
        <SilenceInterval>-PT1S</SilenceInterval>
        <Latency>-PT1S</Latency>
        <SilenceOverrideInterval>-PT1S</SilenceOverrideInterval>
        <ForceRebuildInterval>-PT1S</ForceRebuildInterval>
        <AggregationStorage>MolapOnly</AggregationStorage>
        <Source xsi:type="ProactiveCachingInheritedBinding">
          <NotificationTechnique>Server</NotificationTechnique>
        </Source>
      </ProactiveCaching>
      <EstimatedRows>60398</EstimatedRows>
      <AggregationDesignID>Internet Sales</AggregationDesignID>
    </Partition>
  </ObjectDefinition>
</Alter>

If we were to merge the January and February partitions we created previously, we could change the slice definition to include both months.

<Slice>{[Date].[Calendar].[Month].&amp;[2011]&amp;[1],[Date].[Calendar].[Month].&amp;[2011]&amp;[2]}</Slice>

Setting the Storage Location

Partitions also support the ability to change the storage location for each partition further capitalizing on hardware investments such as SSDs and low cost disks.  This is set in the XMLA using the StorageLocation element with a valid path.

<Alter AllowCreate="true" ObjectExpansion="ObjectProperties" xmlns="http://schemas.microsoft.com/analysisservices/2003/engine">
  <Object>
    <DatabaseID>Adventure Works DW 2008R2 SE2</DatabaseID>
    <CubeID>Adventure Works DW</CubeID>
    <MeasureGroupID>Fact Internet Sales 1</MeasureGroupID>
    <PartitionID>Internet_Sales_Jan2011</PartitionID>
  </Object>
  <ObjectDefinition>
    <Partition xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ddl2="http://schemas.microsoft.com/analysisservices/2003/engine/2" xmlns:ddl2_2="http://schemas.microsoft.com/analysisservices/2003/engine/2/2" xmlns:ddl100_100="http://schemas.microsoft.com/analysisservices/2008/engine/100/100" xmlns:ddl200="http://schemas.microsoft.com/analysisservices/2010/engine/200" xmlns:ddl200_200="http://schemas.microsoft.com/analysisservices/2010/engine/200/200" xmlns:ddl300="http://schemas.microsoft.com/analysisservices/2011/engine/300" xmlns:ddl300_300="http://schemas.microsoft.com/analysisservices/2011/engine/300/300">
      <ID>Internet_Sales_Jan2011</ID>
      <Name>Internet_Sales_Jan2011</Name>
      <Source xsi:type="QueryBinding">
        <DataSourceID>Adventure Works DW</DataSourceID>
        <QueryDefinition>SELECT * 
                        FROM dbo.FactInternetSales 
                        WHERE OrderDateKey BETWEEN 20110101 AND 20110131</QueryDefinition>
      </Source>
      <StorageMode>Molap</StorageMode>
      <ProcessingMode>Regular</ProcessingMode>
      <StorageLocation>C:\Data\SSASOptimized</StorageLocation>
      <ProactiveCaching>
        <SilenceInterval>-PT1S</SilenceInterval>
        <Latency>-PT1S</Latency>
        <SilenceOverrideInterval>-PT1S</SilenceOverrideInterval>
        <ForceRebuildInterval>-PT1S</ForceRebuildInterval>
        <AggregationStorage>MolapOnly</AggregationStorage>
        <Source xsi:type="ProactiveCachingInheritedBinding">
          <NotificationTechnique>Server</NotificationTechnique>
        </Source>
      </ProactiveCaching>
      <EstimatedRows>60398</EstimatedRows>
      <AggregationDesignID>Internet Sales</AggregationDesignID>
    </Partition>
  </ObjectDefinition>
</Alter>

As you can see, there are many partition management operations that can be done using XMLA.  As you work to develop a management strategy keep in mind that these operations can be scripted for automated execution when managing your Analysis Services solution.

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X-XMLA: vi. Processing and Out-of-Line Bindings in XMLA

image_thumb_thumbIn this post, I will progressively go through processing a partition from full process, to incremental process, and finally to incremental process with out-of-line bindings.  This will provide you with additional samples to examine the results of partition processing with XMLA.

Note: these examples use the Adventure Works DW 2008R2 SE sample database available on CodePlex (http://msftdbprodsamples.codeplex.com/).

Processing with XMLA

Processing is a command that can be executed in a batch and in parallel with similar tasks.  This is particularly useful when processing multiple objects that are not dependent on each other, such as dimensions.  The basic structure is as follows:

<Batch>
<Parallel>
<Process>
<Object>
~object definition~
      <Type>
<ErrorConfiguration>
<WriteBackTableCreation>

Processing Type Options

This is a list of the most commonly used types when processing SSAS objects.

  • ProcessDefault:  This will determine the best option based on the condition of the object.  Be aware that if SSAS determines that a full process is required, it will do that. I would not recommend using this process type in most production situations.
  • ProcessFull: This option completely rebuilds the dimension, partition, cube or even database by removing existing data and reloading the data with aggregations and indexes.  In the case of cubes, measure groups and partitions, this is the equivalent of ProcessData + ProcessIndex.
  • ProcessClear: This option drops the data and related structures such as indexes and aggregations from the object.  Once this run, no data is available in the object.
  • ProcessData:  This option drops the data and reloads it, but does not rebuild the aggregations or indexes. It works with cubes, measure groups, partitions, and dimensions.
  • ProcessAdd: This option adds new data to a partition or dimension.  It is not available as an option when processing dimensions from SQL Server Management Studio, but is available in XMLA scripts.
  • ProcessUpdate:  This options will reread the data and updates the dimension attributes.  It is only available for dimensions and will drop flexible aggregations and indexes on related partitions.
  • ProcessIndex: This option rebuilds indexes and aggregations for partitions.  It requires that the partition has already been loaded with data (ProcessData).

Of these options, the most commonly used when working with XMLA in my experience have been, ProcessFull, ProcessData, ProcessAdd and ProcessIndex.  I will use each throughout the examples below and describe the cases where they have applied in my projects over the years.

Processing with XMLA

The process command in XMLA let’s you define the object to be processed, the type of processing to implement, and how to handle any writeback partitions.  (NOTE: the ErrorConfiguration options is optional.) Overall the structure is fairly simple.  Here is a simple example of XMLA will fully process the Fact Internet Sales measure group.

   1: <Batch xmlns="http://schemas.microsoft.com/analysisservices/2003/engine">

   2:   <Parallel>

   3:     <Process xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ddl2="http://schemas.microsoft.com/analysisservices/2003/engine/2" xmlns:ddl2_2="http://schemas.microsoft.com/analysisservices/2003/engine/2/2" xmlns:ddl100_100="http://schemas.microsoft.com/analysisservices/2008/engine/100/100" xmlns:ddl200="http://schemas.microsoft.com/analysisservices/2010/engine/200" xmlns:ddl200_200="http://schemas.microsoft.com/analysisservices/2010/engine/200/200" xmlns:ddl300="http://schemas.microsoft.com/analysisservices/2011/engine/300" xmlns:ddl300_300="http://schemas.microsoft.com/analysisservices/2011/engine/300/300">

   4:       <Object>

   5:         <DatabaseID>Adventure Works DW 2008R2 SE</DatabaseID>

   6:         <CubeID>Adventure Works DW</CubeID>

   7:         <MeasureGroupID>Fact Internet Sales 1</MeasureGroupID>

   8:       </Object>

   9:       <Type>ProcessFull</Type>

  10:       <WriteBackTableCreation>UseExisting</WriteBackTableCreation>

  11:     </Process>

  12:   </Parallel>

  13: </Batch>

The syntax is identical for processing dimensions.  The <Object> element identifies the object to be processed starting with the database.  Next the <Type> element specifies the processing type using the options from the list above.  Finally, the <WriteBackTableCreation> element instructs Analysis Services on how to handle a write back partition that has not been fully processed.  The default is UseExisting which will use existing table or create a new table if needed.  This is only relevant if your cube supports writeback.

Processing Affected Objects

This is a setting that is part of the Process command element.  By default it is set to True as in the example above.  This means that any objects that are affected will be processed as well.  The best example is if you process a dimension and it ends up being fully processed, this will cause all related measure groups to be fully processed as well, keeping the data in a consistent usable state.  However, if you are tightly managing your processing jobs, you may need to set this to False to reduce unexpected and blocking processing jobs.

Using Out-of-Line Binding with Incremental Processing

A great feature of XMLA is the ability to dynamically bind data and even connections when processing SSAS objects.  This is called “Out-of-Line” binding (http://msdn.microsoft.com/en-us/library/ms128523).   One of the core concepts behind out-of-line bindings is that you can specify the connection and the data source query or table at run time.  This is particularly useful when you want to do incremental processing.

This first example illustrates how to use a query to change the data being added to the partition.

   1: <Batch xmlns="http://schemas.microsoft.com/analysisservices/2003/engine">

   2:   <Parallel>

   3:     <Process xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ddl2="http://schemas.microsoft.com/analysisservices/2003/engine/2" xmlns:ddl2_2="http://schemas.microsoft.com/analysisservices/2003/engine/2/2" xmlns:ddl100_100="http://schemas.microsoft.com/analysisservices/2008/engine/100/100" xmlns:ddl200="http://schemas.microsoft.com/analysisservices/2010/engine/200" xmlns:ddl200_200="http://schemas.microsoft.com/analysisservices/2010/engine/200/200" xmlns:ddl300="http://schemas.microsoft.com/analysisservices/2011/engine/300" xmlns:ddl300_300="http://schemas.microsoft.com/analysisservices/2011/engine/300/300">

   4:       <Object>

   5:         <DatabaseID>Adventure Works DW 2008R2 SE</DatabaseID>

   6:         <CubeID>Adventure Works DW</CubeID>

   7:         <MeasureGroupID>Fact Internet Sales 1</MeasureGroupID>

   8:         <PartitionID>Internet_Sales</PartitionID>

   9:       </Object>

  10:       <Type>ProcessAdd</Type>

  11:       <WriteBackTableCreation>UseExisting</WriteBackTableCreation>

  12:     </Process>

  13:   </Parallel>

  14:   <Bindings>

  15:     <Binding>

  16:       <DatabaseID>Adventure Works DW 2008R2 SE</DatabaseID>

  17:       <CubeID>Adventure Works DW</CubeID>

  18:       <MeasureGroupID>Fact Internet Sales 1</MeasureGroupID>

  19:       <PartitionID>Internet_Sales</PartitionID>

  20:       <Source xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ddl2="http://schemas.microsoft.com/analysisservices/2003/engine/2" xmlns:ddl2_2="http://schemas.microsoft.com/analysisservices/2003/engine/2/2" xmlns:ddl100_100="http://schemas.microsoft.com/analysisservices/2008/engine/100/100" xmlns:ddl200="http://schemas.microsoft.com/analysisservices/2010/engine/200" xmlns:ddl200_200="http://schemas.microsoft.com/analysisservices/2010/engine/200/200" xmlns:ddl300="http://schemas.microsoft.com/analysisservices/2011/engine/300" xmlns:ddl300_300="http://schemas.microsoft.com/analysisservices/2011/engine/300/300" xsi:type="QueryBinding">

  21:         <DataSourceID>Adventure Works DW</DataSourceID>

  22:         <QueryDefinition>Select 1 from SomeTable</QueryDefinition>

  23:       </Source>

  24:     </Binding>

  25:   </Bindings>

  26: </Batch>

The second example shows the syntax for changing a table or view in the bindings.

   1: <Batch xmlns="http://schemas.microsoft.com/analysisservices/2003/engine">

   2:   <Parallel>

   3:     <Process xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ddl2="http://schemas.microsoft.com/analysisservices/2003/engine/2" xmlns:ddl2_2="http://schemas.microsoft.com/analysisservices/2003/engine/2/2" xmlns:ddl100_100="http://schemas.microsoft.com/analysisservices/2008/engine/100/100" xmlns:ddl200="http://schemas.microsoft.com/analysisservices/2010/engine/200" xmlns:ddl200_200="http://schemas.microsoft.com/analysisservices/2010/engine/200/200" xmlns:ddl300="http://schemas.microsoft.com/analysisservices/2011/engine/300" xmlns:ddl300_300="http://schemas.microsoft.com/analysisservices/2011/engine/300/300">

   4:       <Object>

   5:         <DatabaseID>Adventure Works DW 2008R2 SE</DatabaseID>

   6:         <CubeID>Adventure Works DW</CubeID>

   7:         <MeasureGroupID>Fact Internet Sales 1</MeasureGroupID>

   8:         <PartitionID>Internet_Sales</PartitionID>

   9:       </Object>

  10:       <Type>ProcessAdd</Type>

  11:       <WriteBackTableCreation>UseExisting</WriteBackTableCreation>

  12:     </Process>

  13:   </Parallel>

  14:   <Bindings>

  15:     <Binding>

  16:       <DatabaseID>Adventure Works DW 2008R2 SE</DatabaseID>

  17:       <CubeID>Adventure Works DW</CubeID>

  18:       <MeasureGroupID>Fact Internet Sales 1</MeasureGroupID>

  19:       <PartitionID>Internet_Sales</PartitionID>

  20:       <Source xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:ddl2="http://schemas.microsoft.com/analysisservices/2003/engine/2" xmlns:ddl2_2="http://schemas.microsoft.com/analysisservices/2003/engine/2/2" xmlns:ddl100_100="http://schemas.microsoft.com/analysisservices/2008/engine/100/100" xmlns:ddl200="http://schemas.microsoft.com/analysisservices/2010/engine/200" xmlns:ddl200_200="http://schemas.microsoft.com/analysisservices/2010/engine/200/200" xmlns:ddl300="http://schemas.microsoft.com/analysisservices/2011/engine/300" xmlns:ddl300_300="http://schemas.microsoft.com/analysisservices/2011/engine/300/300" xsi:type="TableBinding">

  21:         <DataSourceID>Adventure Works DW</DataSourceID>

  22:         <DbTableName>Fact_InternetSales</DbTableName>

  23:       </Source>

  24:     </Binding>

  25:   </Bindings>

  26: </Batch>

In the end, by using the Bindings definitions you can choose what data is getting processed into the SSAS object.  Here are some ways that I have used this technique to support my projects.

  • Changed the datasource used with the object.  I have used this to point to a different data source to test whether it works with the cube without overwriting the existing datassource in the cube definition.
  • Changed the table to a view for processing.  Because I use XMLA when scheduling most of SSAS process jobs, I can dynamically set the table or view as needed.
                        • Changed the query definition to limit the data to new rows only. I have used this the most.  I have changed the query definition to reflect the latest data for both dimensions and partitions.  More importantly, I was able to leverage this in environments where I have not had control over the data source itself, specifically Oracle data warehouses.

Out-of-line bindings are very powerful when controlling your SSAS process options and allow you to maximize the efficiency of your jobs.

Troubleshooting a Data Type Issue during SSAS Processing

Situation

I have built a cube on a series of views in SQL Server that mimicked similar views in Oracle.  The views create a “virtual star schema” over an operational data store that consists of imports from various mainframe sources.  There is no plan at the moment to move to a stored star schema, so views are being used to fill the gap.  During the development cycle issues arose with performance from the Oracle environment.  While those issues were being investigated, the data store tables used to support the SSAS project were moved to a SQL Server instance for the interim.  We retained the views to minimize the impact for delivery once Oracle issues were resolved.

I am currently deploying changes only from Visual Studio (see image below for Project Configuration settings).  After that, I used SSMS with XMLA to process the dimensions and measure groups in a targeted fashion.

clip_image001

Issue

The issue was that along the way, the data types had to be adjusted to support the more robust data typing in SQL Server.  As a result of the data type changes, I started to see errors during processing which noted that the data was being truncated.

Troubleshooting

I tried a number of things to resolve this particular error.  Along the way I fixed other various but unrelated issues.  Here are the activities I tried to resolve the issue which did not work.

  • Rebuild all dimensions
  • Reviewed ALL relationships, keys, and measures for offending data types.  Some of this was reviewed through the BIDSHelper tool – Dimension Data Type Discrepancy Check.
  • Reduced data set.  This returned the error faster, but also allowed for quicker processing during the resolution of the issue.
  • Eliminated relationships and measures.  As this issue was clearly in the measure group, I removed the relationships and the currency measure from the measure group.  This worked.

Resolution

The last step was the key piece – by eliminating the relationships, I was able to determine which reset all of the relationship values.  While I had done this manually, it appears that I needed to remove all of the relationships and then add them back in as I processed.  This appears to have resolved the issue I was encountering.

The moral of this story is that the BIDSHelper tool showed me where the error was likely occurring, but as is the case with many of the BI tools in Visual Studio, the change was not propagating to all of the locations required within the XMLA until I retouched them all.  Now if I can just get the memory to release properly, but that is a topic for another day.