List new features in TOM library

How-to: Auto-generate a list of new features released in Analysis Services Tabular

This week, a new version (19.2.0.2) of the Tabular Object Model (TOM) was released on NuGet. In fact, this is a major version jump from the previous 18.7 release:

NuGet Version History

Those updates have been more frequent recently, and they usually coincide with new features coming to Azure Analysis Services or Power BI (Premium), and allow open-source tools like Tabular Editor to support those features.

So, those releases are generally very happy occasions and allow to become more productive with the wider Power BI ecosystem. However, it has always bothered me that the AMO/TOM libraries come with very sparse documentation, and virtually no change log or release notes. Lots of the functionality has to be discovered the hard way by trial and error.

The 19.x version number has made me particularly curious this time, and I wanted to know more. I remembered from previous use of TOM that I would occasionally receive a CompatibilityViolationException when running some code against an older on-prem Tabular server, for instance.

Taking a quick look inside reveals that certain parts of the API are annotated with an CompatibilityRequirement attribute:

CompatibilityRequirementAttribute

The number referenced there clearly corresponds to the well-known Compatibility Level for tabular models. Remember, 1200 was the level that properly kicked off tabular modeling with the introduction of TMSL, and 1400 was another milestone with the introduction of M/PowerQuery integration into Tabular and structured data sources.

Since the tight integration between Analysis Services and Power BI, quite a few new compatibility levels have been introduced, very recently 1520 in conjunction with the enhanced PBIX metadata format.

So it didn't take very long to write a little LinqPad script to automatically extract and list all TOM API elements that happen to be annotated with that [CompatibilityRequirement] attribute.

Turns out the attribute internally distinguishes three different scopes, namely: "Box" (presumably on-prem SSAS), "Excel", and "Pbi". Since 1400 has been around for a long time now, the results are split into two tables below: All features introduced after 1400 first, then all others that are marked with 1200, 1400, or Unsupported.

How to read this? To take an example, the features around Calculation Groups were introduced with level 1470 (which is also mentioned in Kaspar's blog post here). However, the ability to define a custom sort order for calculation items via the Ordinal property was only introduced with the 1500 level, hence requires a model at that level and a server that supports it as well.

Having checked one of our production Azure Analysis Services servers, they currently report those SupportedCompatibilityLevels: 1100,1103,1200,1400,1450,1455,1460,1465,1470,1475,1480,1500,1510,1520,1530,1000000, i.e. go up as far as 1530.

Hence, it is very interesting to see one item listing "1535" below (MAttributes), and even some explicitly marked as "Preview" (AnalyticsAIMetadata).

What is going to be announced here??

In any case, I hope this helps some folks (like myself) getting a bit more clarity about the features supported by the TOM API, and how those relate to the various new compatibility levels that were introduced post-1400.

The script used here is provided at the bottom, and can easily be re-run with any future releases appearing on NuGet!

Table 1: Post-1400 Features

Name	MemberType	Box	Excel	Power BI
AlternateOf	Class	1460	1460	1460
AlternateOfAnnotationCollection	Class	1460	1460	1460
AnalyticsAIMetadata	Class	Preview	Preview	Preview
AnalyticsAIMetadataCollection	Class	Preview	Preview	Preview
BasicRefreshPolicy	Class	1450	1450	1450
CalculationGroup	Class	1470	1470	1470
CalculationGroupAnnotationCollection	Class	1470	1470	1470
CalculationGroupSource	Class	1470	1470	1470
CalculationItem	Class	1470	1470	1470
CalculationItem.Ordinal	Property	1500	1500	1500
CalculationItemCollection	Class	1470	1470	1470
Column.AlternateOf	Property	1460	1460	1460
ContentType	Enum	1465	1465	1465
DataSourceVariablesOverrideBehaviorType	Enum	1475	1475	1475
FormatStringDefinition	Class	1470	1470	1470
LinguisticMetadata.ContentType	Property	1465	1465	1465
Measure.DataCategory	Property	1455	1455	1455
Model.AnalyticsAIMetadata	Property	Preview	Preview	Preview
Model.DataSourceDefaultMaxConnections	Property	1510	1510	1510
Model.DataSourceVariablesOverrideBehavior	Property	1475	1475	1475
Model.DefaultPowerBIDataSourceVersion	Property	1450	1450	1450
Model.DiscourageImplicitMeasures	Property	1470	1470	1470
Model.ForceUniqueNames	Property	1465	1465	1465
Model.MAttributes	Property	1535	1535	1535
Model.QueryGroups	Property	1480	1480	1480
Model.SourceQueryCulture	Property	1520	1520	1520
ModeType.Dual	Field	1455	1455	1455
NamedExpression.MAttributes	Property	1535	1535	1535
NamedExpression.ParameterValuesColumn	Property	Preview	Preview	Preview
NamedExpression.QueryGroup	Property	1480	1480	1480
Partition.QueryGroup	Property	1480	1480	1480
PartitionSourceType.CalculationGroup	Field	1470	1470	1470
PartitionSourceType.PolicyRange	Field	1450	1450	1450
PolicyRangePartitionSource	Class	1450	1450	1450
PowerBIDataSourceVersion	Enum	1450	1450	1450
PowerBIDataSourceVersion.PowerBI_V3	Field	1465	1465	1465
QueryGroup	Class	1480	1480	1480
QueryGroupAnnotationCollection	Class	1480	1480	1480
QueryGroupCollection	Class	1480	1480	1480
RefreshGranularityType	Enum	1450	1450	1450
RefreshPolicy	Class	1450	1450	1450
RefreshPolicyAnnotationCollection	Class	1450	1450	1450
RefreshPolicyExtendedPropertyCollection	Class	1450	1450	1450
RefreshPolicyType	Enum	1450	1450	1450
SummarizationType	Enum	1460	1460	1460
Table.AlternateSourcePrecedence	Property	1460	1460	1460
Table.CalculationGroup	Property	1470	1470	1470
Table.ExcludeFromModelRefresh	Property	1480	1480	1480
Table.RefreshPolicy	Property	1450	1450	1450

Table 2: 1200/1400 Features

Name	MemberType	Box	Excel	Power BI
AttributeHierarchy.ExtendedProperties	Property	1400	1400	1400
AttributeHierarchyExtendedPropertyCollection	Class	1400	1400	1400
CalculatedPartitionSource.RetainDataTillForceCalculate	Property	1400	1400	1400
Column.EncodingHint	Property	1400	1400	1400
Column.ExtendedProperties	Property	1400	1400	1400
Column.RelatedColumnDetails	Property	Unsupported	Unsupported	1400
Column.Variations	Property	1400	1400	1200
ColumnExtendedPropertyCollection	Class	1400	1400	1400
ColumnPermission	Class	1400	1400	1400
ColumnPermissionAnnotationCollection	Class	1400	1400	1400
ColumnPermissionCollection	Class	1400	1400	1400
ColumnPermissionExtendedPropertyCollection	Class	1400	1400	1400
ConnectionAddress	Class	1400	1400	1400
ConnectionDetails	Class	1400	1400	1400
Credential	Class	1400	1400	1400
Culture.ExtendedProperties	Property	1400	1400	1400
CultureExtendedPropertyCollection	Class	1400	1400	1400
DataAccessOptions	Class	1400	1400	1400
DataRefresh.MPartitionSourceOverride	Class	1400	1400	1400
DataRefresh.NamedExpressionOverride	Class	1400	1400	1400
DataRefresh.StructuredDataSourceOverride	Class	1400	1400	1400
DataSource.ExtendedProperties	Property	1400	1400	1400
DataSourceExtendedPropertyCollection	Class	1400	1400	1400
DataSourceOptions	Class	1400	1400	1400
DataSourceType.Structured	Field	1400	1400	1400
DetailRowsDefinition	Class	1400	1400	1400
EncodingHintType	Enum	1400	1400	1400
EntityPartitionSource	Class	1400	1400	1400
ExpressionKind	Enum	1400	1400	1400
ExtendedProperty	Class	1400	1400	1400
ExtendedPropertyType	Enum	1400	1400	1400
GroupByColumn	Class	Unsupported	Unsupported	1400
GroupByColumnCollection	Class	Unsupported	Unsupported	1400
Hierarchy.ExtendedProperties	Property	1400	1400	1400
Hierarchy.HideMembers	Property	1400	1400	1400
HierarchyExtendedPropertyCollection	Class	1400	1400	1400
HierarchyHideMembersType	Enum	1400	1400	1400
JsonExtendedProperty	Class	1400	1400	1400
KPI.ExtendedProperties	Property	1400	1400	1400
KPIExtendedPropertyCollection	Class	1400	1400	1400
Level.ExtendedProperties	Property	1400	1400	1400
LevelExtendedPropertyCollection	Class	1400	1400	1400
LinguisticMetadata.ExtendedProperties	Property	1400	1400	1400
LinguisticMetadataExtendedPropertyCollection	Class	1400	1400	1400
Measure.DetailRowsDefinition	Property	1400	1400	1400
Measure.ExtendedProperties	Property	1400	1400	1400
MeasureExtendedPropertyCollection	Class	1400	1400	1400
MetadataPermission	Enum	1400	1400	1400
Model.DefaultMeasure	Property	1400	1400	1400
Model.Expressions	Property	1400	1400	1400
Model.ExtendedProperties	Property	1400	1400	1400
ModelExtendedPropertyCollection	Class	1400	1400	1400
ModelRole.ExtendedProperties	Property	1400	1400	1400
ModelRoleExtendedPropertyCollection	Class	1400	1400	1400
ModelRoleMember.ExtendedProperties	Property	1400	1400	1400
ModelRoleMemberExtendedPropertyCollection	Class	1400	1400	1400
ModeType.Push	Field	Unsupported	Unsupported	1200
MPartitionSource	Class	1400	1400	1400
NamedExpression	Class	1400	1400	1400
NamedExpressionAnnotationCollection	Class	1400	1400	1400
NamedExpressionCollection	Class	1400	1400	1400
NamedExpressionExtendedPropertyCollection	Class	1400	1400	1400
ObjectState.ForceCalculationNeeded	Field	Unsupported	Unsupported	1400
Partition.ExtendedProperties	Property	1400	1400	1400
Partition.RetainDataTillForceCalculate	Property	1400	1400	1400
PartitionExtendedPropertyCollection	Class	1400	1400	1400
PartitionSourceType.Entity	Field	1400	1400	1400
PartitionSourceType.M	Field	1400	1400	1400
Perspective.ExtendedProperties	Property	1400	1400	1400
PerspectiveColumn.ExtendedProperties	Property	1400	1400	1400
PerspectiveColumnExtendedPropertyCollection	Class	1400	1400	1400
PerspectiveExtendedPropertyCollection	Class	1400	1400	1400
PerspectiveHierarchy.ExtendedProperties	Property	1400	1400	1400
PerspectiveHierarchyExtendedPropertyCollection	Class	1400	1400	1400
PerspectiveMeasure.ExtendedProperties	Property	1400	1400	1400
PerspectiveMeasureExtendedPropertyCollection	Class	1400	1400	1400
PerspectiveSet	Class	Unsupported	Unsupported	1400
PerspectiveSetAnnotationCollection	Class	Unsupported	Unsupported	1400
PerspectiveSetCollection	Class	Unsupported	Unsupported	1400
PerspectiveSetExtendedPropertyCollection	Class	Unsupported	Unsupported	1400
PerspectiveTable.ExtendedProperties	Property	1400	1400	1400
PerspectiveTable.PerspectiveSets	Property	Unsupported	Unsupported	1400
PerspectiveTableExtendedPropertyCollection	Class	1400	1400	1400
RelatedColumnDetails	Class	Unsupported	Unsupported	1400
Relationship.ExtendedProperties	Property	1400	1400	1400
RelationshipExtendedPropertyCollection	Class	1400	1400	1400
Set	Class	Unsupported	Unsupported	1400
SetAnnotationCollection	Class	Unsupported	Unsupported	1400
SetCollection	Class	Unsupported	Unsupported	1400
SetExtendedPropertyCollection	Class	Unsupported	Unsupported	1400
StringExtendedProperty	Class	1400	1400	1400
StructuredDataSource	Class	1400	1400	1400
Table.DefaultDetailRowsDefinition	Property	1400	1400	1400
Table.ExtendedProperties	Property	1400	1400	1400
Table.IsPrivate	Property	1400	1400	1200
Table.Sets	Property	Unsupported	Unsupported	1400
Table.ShowAsVariationsOnly	Property	1400	1400	1200
TableExtendedPropertyCollection	Class	1400	1400	1400
TablePermission.ColumnPermissions	Property	1400	1400	1400
TablePermission.ExtendedProperties	Property	1400	1400	1400
TablePermission.MetadataPermission	Property	1400	1400	1400
TablePermissionExtendedPropertyCollection	Class	1400	1400	1400
Variation	Class	1400	1400	1200
VariationAnnotationCollection	Class	1400	1400	1200
VariationCollection	Class	1400	1400	1200
VariationExtendedPropertyCollection	Class	1400	1400	1400

LINQPad script

Requires NuGet package: Microsoft.AnalysisServices.retail.amd64 and namespace declaration: TOM = Microsoft.AnalysisServices.Tabular.

• TOM-Extract-CompatibilityRequirementsAttributes.linq file available in this Gist.

var asm = typeof(TOM.Server).Assembly;
var compatAttr = asm.GetType("Microsoft.AnalysisServices.Tabular.CompatibilityRequirementAttribute");

string ReadProperty(string name, object attr) => compatAttr.GetProperty(name).GetValue(attr).ToString();
string GetMemberType(Type t) => t.IsEnum ? "Enum" : t.IsInterface ? "Interface" : "Class";
Attribute GetCustomAttributeSafe(MemberInfo member, Type t) 
{ // This is needed to avoid errors on a few specific attributes containing unsupported expressions - we're simply ignoring those
    try {
        return member.GetCustomAttribute(t);
    }
    catch (TOM.TomException) {
        return null;
    }
}

var members = asm.GetTypes()
    .Select(t => new
    {
        Type = t,
        CompatAttribute = t.GetCustomAttribute(compatAttr)
    })
    .Where(x => x.CompatAttribute != null)
    .Select(x => new 
    {
        Name = x.Type.FullName,
        MemberType = GetMemberType(x.Type),
        Box = ReadProperty("Box", x.CompatAttribute),
        Excel = ReadProperty("Excel", x.CompatAttribute),
        PBI = ReadProperty("Pbi", x.CompatAttribute)
    })
    .Union(
        asm.GetTypes()
        .SelectMany(t => t.GetMembers())
        .Select(m => new 
        {
            Member = m,
            Name = $"{m.DeclaringType.FullName}.{m.Name}",
            CompatAttribute = GetCustomAttributeSafe(m, compatAttr),
            MemberType = m.MemberType.ToString()
        })
        .Where(x => x.CompatAttribute != null)
        .Select(x => new
        {
            x.Name, 
            x.MemberType,
            Box = ReadProperty("Box", x.CompatAttribute),
            Excel = ReadProperty("Excel", x.CompatAttribute),
            PBI = ReadProperty("Pbi", x.CompatAttribute)
        })
    )
    .Where(x => /* toggle this for 1200/1400: */ !(((int.TryParse(x.Box, out var box) && box <= 1400) || x.Box == "Unsupported")
        && ((int.TryParse(x.Excel, out var excel) && excel <= 1400) || x.Excel == "Unsupported")
        && ((int.TryParse(x.PBI, out var pbi) && pbi <= 1400) || x.PBI == "Unsupported")))
    .OrderBy(x => x.Name)
    .ToArray()
    .Dump();

// Convert to markdown table for blog post:
Array.ForEach(members, x => $"| {x.Name.Substring("Microsoft.AnalysisServices.Tabular.".Length)} | {x.MemberType} | {x.Box} | {x.Excel} | {x.PBI} |".Dump());