Here's why we should use chronological key if we have a Time dimension in our data model.
Compared to modeling an ordinary dimension, the time dimension requires just two additional steps: selecting the Time option in the Logical Dimension dialog box and designating a chronological key for every level of the dimension hierarchy.
At query time, Oracle BI Server then generates highly optimized SQL that pushes the time offset processing down to the database whenever possible, resulting in the best performance and functionality.
Designate a chronological key for every level of each dimension hierarchy. This key must meet the requirements of being sequential (the members have a natural order), cardinal (all members are spaced the same distance apart at a given level, such as day or month), and complete (no members missing). Oracle BI Server uses the chronological key to create mathematically correct time series predictions, such as “Apr + 2 months = Jun.”
You should set a chronological key for every level (except for the Grand Total level) so that you can perform time series operations on all levels with good performance. This allows you to use an AGO, TODATE, or PERIODROLLING function for any level of any time dimension hierarchy, such as fiscal month ago, calendar year ago, and day ago. As with any level key, be sure the key is unique at its level. In this example, the Day column is set as the chronological key for the Time Detail level.
can you please mark and close this thread if you are satisfied by the answer given above?
if you don't mind can y tell me solution for this
i have requirement i need create two hierarchy calender table cantains calender year data and fiscal year data
in this case which one approach i need follow
case1>i need create alias tables two one for calender data and anethor one fiscal year table in physical layer
case 2>i need create duplicate table in bmm layer 1 table caintains calender data and anether table contain fiscal year table
which one approch is recomnded way
This is altogether a new thread. People will respond in a separate thread. You close this thread if Sagar's response was helpful.