LinkMember

The built-in LinkMember function may not behave as you are expecting. For instance, the following query returns [Ship Date].[Calendar].[H1 CY 2004] not [Ship Date].[Calendar].[January 2004]:

select {} on 0,
LinkMember([Date].[Calendar].[January 2004],[Ship Date].[Calendar]) on 1
from [Adventure Works]

The stored procedures in the LinkMember class provide an alternative to this behavior. The following query returns [Ship Date].[Calendar].[January 2004] as you were expecting:

select {} on 0,
ASSP.HierarchyLinkMember([Date].[Calendar].[January 2004],"[Ship Date].[Calendar]") on 1
from [Adventure Works]

The signatures for these functions are as follows:

HierarchyLinkMember(Member, HierarchyUniqueNameString)

This function returns the member with keys and level matching the member passed in as the first parameter. It searches within the hierarchy specified in the second parameter.

LevelLinkMember(Member, LevelUniqueNameString)

This function returns the member with keys matching the member passed in as the first parameter. It searches within the level specified in the second parameter.


General Note: The signature of the stored proc asks for the hierarchy unique name as a string. This signature allows the function to run 50 times faster than if a Hierarchy object were used as the parameter.

It should be noted that this could be accomplished with plain MDX. If you know that a month has been selected, the MDX could use the attribute hierarchy and read as follows:

select {} on 0,
LinkMember([Date].[Calendar].[January 2004],[Ship Date].[Month Name]) on 1
from [Adventure Works]

However, if the level (quarter, month, etc.) is now known ahead of time, the MDX must be more complex:

select {} on 0,
case
 when [Date].[Calendar].CurrentMember.Level is [Date].[Calendar].[Calendar Year]
  then LinkMember([Date].[Calendar].CurrentMember,[Ship Date].[Calendar Year])
 when [Date].[Calendar].CurrentMember.Level is [Date].[Calendar].[Calendar Semester]
  then LinkMember([Date].[Calendar].CurrentMember,[Ship Date].[Calendar Semester])
 when [Date].[Calendar].CurrentMember.Level is [Date].[Calendar].[Calendar Quarter]
  then LinkMember([Date].[Calendar].CurrentMember,[Ship Date].[Calendar Quarter])
 when [Date].[Calendar].CurrentMember.Level is [Date].[Calendar].[Month]
  then LinkMember([Date].[Calendar].CurrentMember,[Ship Date].[Month Name])
 when [Date].[Calendar].CurrentMember.Level is [Date].[Calendar].[Date]
  then LinkMember([Date].[Calendar].CurrentMember,[Ship Date].[Date])
end
on 1
from [Adventure Works]
where ([Date].[Calendar].[January 2004])

Last edited Jun 22, 2007 at 11:50 PM by dgosbell, version 3