The public CTP 2.1 of SQL Server 2017 is available here! This public preview includes the following enhancements for Analysis Services tabular models.
- Shared M expressions are shown in the SSDT Tabular Model Explorer, and can be maintained using the Query Editor.
- Data Management View (DMV) improvements.
- Opening an file with the .MSDAX extension in SSDT enables DAX non-model related IntelliSense.
- Encoding hints can be set in the SSDT properties window.
Shared M expressions
Shared M expressions are shown in the Tabular Model Explorer in SSDT! By right clicking the Expressions node, you can edit the expressions in the Query Editor. This should seem familiar to Power BI Desktop users.
The following query returns the output shown below. M expressions and structured data sources are included for 1400 models.
SELECT * FROM $System.DISCOVER_CALC_DEPENDENCY WHERE OBJECT_TYPE = 'PARTITION' OR OBJECT_TYPE = 'EXPRESSION';
The output is a superset of the information shown by the Query Dependencies visual, which is available in SSDT from the Query Editor.
This information is useful for numerous scenarios including the following.
- Documentation of tabular models.
- Community tools such as BISM Normalizer that perform incremental metadata deployment and merging, as well as other 3rd party tools, can use it for impact analysis.
CTP 2.1 provides a fix for MDSCHEMA_MEASUREGROUP_DIMENSIONS. This DMV is used by various client tools to show measure dimensionality. For example, the Explore feature in Excel Pivot Tables allows the user to cross-drill to dimensions related to the selected measures.
Prior to CTP 2.1, some rows were missing in the output for 1200 models, which meant the Explore feature did not work correctly. This is fixed in CTP 2.1.
We intend to make further DMV improvements in forthcoming releases, so stay tuned.
DAX file editing
Opening a file with the .MSDAX extension in SSDT allows DAX editing with non-model related IntelliSense such as highlighting, statement completion and parameter info. As you can imagine, we intend to use this for interesting features to be released in the future!
As documented in this blog post, encoding hints are an advanced feature introduced by CTP 1.3. They can help optimization of processing (data refresh) for large in-memory tabular models. In CTP 2.1, encoding hints can be set in the SSDT Visual Studio properties window.
Be sure to keep an eye on this blog to stay up to date on Analysis Services!