IBM Cognos, Руководство пользователя

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We recommend choosing this method if you want to keep the lunar year aligned
with the calendar year or your fiscal year, a requirement in most business
operations.
Procedure
1. On the Dimension Map , create a new time dimension with automatically
added levels.
2. Open the property sheet for the Year level and click the Time tab.
3. In the Date function box, select the Lunar year function to create a level based
on lunar years.
4.
Repeat steps 2 and 3 for the Quarter and Month levels, selecting the
appropriate function.
Specify How Extra Weeks Get Added to Lunar Years
A lunar year contains 52 weeks of seven days each, for a total of 364 days. This
represents either one or two fewer days than the standard calendar or leap year,
respectively. However, your model design must keep each lunar year aligned with
its specified Start-of-Year day, while not falling too far out of alignment with the
calendar year.
To support this goal, you can specify whether the extra one or two days get added
as an extra week in the last month or the last quarter of the year.
When you create alternate drill-down paths in a lunar time dimension, if the
convergence level is
Week , Lunar month , or Lunar quarter , you must match both
the Week begins on setting and the Add an extra week setting for all drill-down
paths.
If the last lunar month in the year has five weeks in a 4-4-5 week pattern, the
surplus days create an extra week. The extra week is added to the previous lunar
month to make a 4-5-5 week pattern, rather than a 4-4-6 week pattern, which is not
valid.
Procedure
1. Open the Categories diagram for the lunar time dimension you want to
modify.
2.
Open the property sheet for the drill category that you want to change and
click the
Time tab.
3. In the Add an extra week box, select the setting to apply to the extra days of
each year.
Limit the Range of Dates Included in the Model
When you create the time dimension, you can limit the range of acceptable dates
so that categories that are irrelevant to your users do not appear in their OLAP
reports.
When Cognos Transformer encounters date values outside your specified range, it
generates an
Early Dates
or a
Late Dates
category, or both, depending on when
the out-of-range dates occur. In addition, if there are dates that are neither early
nor late, but can not be placed within the specified range, Cognos Transformer
generates an
Invalid Dates category.
Chapter 4. Structuring Your Data Into Dimensions
77