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Shankar
 
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Default Essbase - Time dimension details - 11-17-2005 , 03:01 AM






Hi,

I am new to Essbase... Have a couple of questions related to the
special dimension Time.

1. Any dimension can be tagged as Time (only one such within an Essbase
database). All dimension members are stored as Strings.. Hence i could
have a Time dimension with Level 0 members as the descriptive days -
"01-JAN-2005", "02-JAN-2005", etc or as a sequence of IDs viz
"2453372", "2453373", etc... Maybe even in some other format
"dd-mm-yyyy" perhaps...

I am unable to understand how these textual time dimension members
become "time-aware".. i.e. i should be able to get the system to tell
me that there are 82 days between 2 random members '28-MAR-2005' and
'05-JAN-2005'.

How do we do this in Essbase? Are there any standard functions to do
this in Essbase? Are there any specific Time *metadata* objects which
are created as a result of tagging a dimension as Time dimension type.

I encountered difficulty in trying to derive a formula for "Sales Last
Year" based on "Sales" since there isn't a neat way to do a subtraction
of an Year within time.


2. Time dimension usually involves a lot of attributes like Day level -
Holiday, Business Day, Season indicators. Maybe a Leap Year indicator
at Year level. In order to associate attributes to any dimension, that
dimension needs to be tagged as a sparse dimension in Essbase. Hence
Time needs to be marked as sparse in Essabse if we want to have these
time based attributes. However for most OLAP applications, time would
be a dense dimension since we usually have data (for all other
measures/dimensions) for each of the time dimension members. Isnt this
incongruous? In other words, is there a way we can have TIME dimension
as dense and also have access to the time based analysis parameters
like calendar Holidays, Seasonal settings etc.

Any help in this regard is welcome.

Thanks
Shankar


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JM
 
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Default Re: Essbase - Time dimension details - 11-18-2005 , 07:11 AM






The time tag is simply used for time balance measures functionality, is
required by some Essbase functions, and allows Dynamic Time Series
aggregations. The other time functionality that you describe does not
natively exist in Essbase, although it could be created by writing
custom java functions.

We stick with the relational world to calculate time stats, and load
the data into Essbase.

Regarding tagging time members with date attributes, consider adding
measures for date attributes, then load a 1 for true. Of course you
could never aggregate these measures, or the data for upper level
members would be wiped out. Another option would be to use UDA's.


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