UnknownMember (MDX)
Returns the unknown member associated with a level or member.
Syntax
Member expression syntax
Member_Expression.UnknownMember
Hierarchy_expression syntax
Hierarchy_Expression.UnknownMember
Arguments
Member_Expression
A valid Multidimensional Expressions (MDX) expression that returns a member.Hierarchy_Expression
A valid Multidimensional Expressions (MDX) expression that returns a hierarchy.
Remarks
Microsoft SQL Server Analysis Services creates an unknown member to associate fact table data with a hierarchy when the hierarchy is not known. The unknown member can be at one of the following levels:
At the top level for attribute hierarchies that are not aggregated.
At the first level below the All level for natural hierarchies.
At any level for unnatural hierarchies.
If a member expression is specified, the UnknownMember function returns the unknown member child of the specified member. If the specified member does not exist, the function returns null.
If a hierarchy expression is specified, the UnknownMember function returns the unknown member at the top level if one exists.
If the unknown member does not exist on the level or member, the UnknownMember function creates a null member.
Note
If the unknown member does not exist on the hierarchy or member, an error is generated.
Examples
The following example returns the unknown member for the All Products member in the Product attribute hierarchy for all members of the Measures dimension.
SELECT [Product].[Product].[All Products].UnknownMember
ON Columns,
[Measures].Members
ON Rows
FROM [Adventure Works]
The following example returns the unknown member for the Product Categories hierarchy for all members of the Measures dimension.
SELECT [Product].[Product Categories].UnknownMember
ON Columns,
[Measures].Members
ON Rows
FROM [Adventure Works]