TOM Compatibility Levels
The missing documentation.
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The missing documentation.
Last updated
Was this helpful?
Ever since the convergence of Analysis Services (Tabular) and Power BI (Premium) has started, the Analysis Services API surface has evolved rapidly. New versions of the are being released frequently, and new Power BI (Premium) features introduce new TOM Compatibility Levels which must be configured at the database in order to enable certain features in the underlying engine.
However, official documentation of those feature sets and the corresponding compatibility levels and NuGet versions is very sparse.
Using the reflection approach described , this page provides "The Missing Documentation" - a chronological listing of TOM features by compatibility level. Major features are annotated with related articles and blog posts.
Release of []
No changes in public API
No changes in public API
Release of []
REMOVED: CalculationGroup.DefaultExpression property (Preview)
REMOVED: CalculationExpression class (Preview)
ADDED: CalculationGroupSelectionMode enum (Preview)
ADDED: CalculationGroupExpression class (Preview)
ADDED: CalculationGroup.MultiSelectionExpression property (Preview)
ADDED: CalculationGroup.NoSelectionExpression property (Preview)
NEW MetadataObject types:
Calendar (Preview)
TimeUnitColumnAssociation (Preview)
CalendarColumnReference (Preview)
ADDED: TimeUnit enum (Preview)
No changes in public API
No changes in public API
The execution flow of ApplyRefreshPolicy is the same as the flow that is triggered by a call to RequestRefresh, followed by a call to Model.SaveChanges.
The execution flow includes:
Calculating the expected partitioning scheme based on the effective date.
Comparing the expected partitioning scheme to the existing set of partitions and issue the needed changes to move to the expected scheme [dropping, creating, and merging partitions as needed].
Refresh the newly created partitions as well as the existing partitions in the incremental window.
The only difference between the ApplyRefreshPolicy and the combination of RequestRefresh+SaveChanges is ApplyRefreshPolicy enables advanced options that are not available otherwise.
It is recommended to use ApplyRefreshPolicy when you want to use a single API call, especially with advanced options.
It is recommended to use the combination of RequestRefresh + SaveChanges when you want to combine the operation with additional authoring calls in the model before the call to SaveChanges.
No changes in public API
DAXEvaluationLog = 135 Output of EvaluateAndLog function.
public AsAzureRedirection AsAzureRedirection { get; }
Hybrid Tables in PBI Premium
API Changes
RefreshPolicyMode.Import: Creates import partitions during incremental refresh.
RefreshPolicyMode.Hybrid: Creates import and DirectQuery partitions during incremental refresh.
Auto Aggregations
API Changes
SourceLineageTag (Column, Hierarchy, Level, Measure, NamedExpression, Table): A tag that represents the lineage of the source for the object.
LineageTag (Column, Hierarchy, Level, Measure, NamedExpression, Table): A tag that represents the lineage of the object.
QueryGroups
Calculation Groups
API Changes
"Enhanced Metadata Format"
API Changes
Dual Storage Mode
API Changes
Incremental Refresh Policy (Import)
API Changes
1100, 1103, 1200, 1400
Release of []
ADDED: (used with )
ADDED:
ADDED: : Create a script to export a database.
MetadataObject type: A tabular DataCoverageDefinition object. The expression defined on this object gives hint about the data in a partition.
: A reference to an optional DataCoverageDefinition that provides the hint regarding the data that is covered by the partition.
Remarks added to , :
Introduces FormatStringDefinition to measures. Previously, those only existed on .
: A reference to a FormatStringDefinition object owned by this Measure.
: Retrieves automatic aggregation recommendations from Analysis Services engine and applies changes to the model.
: Scripts out a given Tabular database into an ApplyAutomaticAggregations command.
: An indication whether the table is excluded from the automatic aggregations feature.
: An indication if the translation of the property had been changed.
: A reference to the NamedExpression where the parameter associated with the remote model.
: The parameter name defined in source model, applicable only for proxy model and empty for local model.
New value in
New property in
: Maximum degree of parallelism for query in formula engine
: Determines the max possible number of parallel tasks in data refresh, within the resource constraints of the hosting service.
ChangedProperties (, , , , , ): Represents an indication of a change to one of the object's properties.
: Disable auto exists behavior for SummarizeColumns.
(Enum)
: The data in this partition is populated by executing a query generated by the system.
: Represents a Partition that its data will be populated by executing a query generated by the system.
: Represents a Partition that its data will be populated by executing a query generated by the system.
: A boolean value that indicates whether the table is managed by the system. The system takes ownership of creation and deletion of such tables.
: No filtering will occur from either end of the relationship.
: Determines whether to discourage composite models.
: Client tools apply filters to this column using M parameter. The presence of this property indicates model owner allows Dax queries to override this parameter, and columns data type must match the type specified in the meta tag of the parameter.
: The string that has M attributes.
: The name of the Culture used for formatting during refresh through Mashup.
: DataSourceDefaultMaxConnections will be used for connections to a data source if MaxConnections is set to -1 on the data source object or if there is no corresponding data source object for the data source.
: The zero-based ordinal value associated with a Calculation Item.
: Gets the collection object of all querygroups in the current Model.
: QueryGroup associated with the expression.
: QueryGroup associated with the partition.
: A boolean value that indicates whether the table is excluded from model refresh. When this is true, a refresh operation on the model would not trigger a refresh on the partitions of the table if they were already processed.
: Controls whether this model allows data source variables to be overriden.
,
: The partition uses CalculationGroup as a source.
: Determines whether to discourage the implicit measures.
: Power BI V3 Data Sources support basic partition management operations.
: Determines whether measures can have the same names as any column in the model.
: Specifies the type of the linguistic metadata from the Content property. E.g. XML or JSON.
(Enum: GroupBy, Sum, Count, Min, Max): Specifies the Summarization type to be used by alternative sources' columns.
: Represents a AlternativeSource object. It is a child of either a Table or a Column object.
: Defines the AlternateOf reference source BaseTable or BaseColumn, and the Summarization.
: The ranking or precedence used to select the alternate source table in case more than one match is found.
: Allows support for dual mode of Import as well as DirectQuery.
: Specifies the type of data contained in the measure so that you can add custom behaviors based on measure type.
(Enum: Day, Month, Quarter, Year)
(Enum: Basic)
: The partition uses an M expression to retrieve the data. The partition ranges are auto created based on RefreshPolicy.
(Enum): DataSource format version in Power BI Service.
: Used by PBIX data source format conversion.