Oracle Certification 1z0-591 Syllabus Exam Questions Answers

Modeling Time Series Function in OBIEE

Modeling Time Series Data

Time series functions provide the ability to compare business performance with previous time periods, allowing you to analyze data that spans multiple time periods. For example, time series functions enable comparisons between current sales and sales a year ago, a month ago, and so on.

Because SQL does not provide a direct way to make time comparisons, you must model time series data in the Oracle BI repository. First, set up time dimensions based on the period table in your data warehouse. Then, you can define measures that take advantage of this time dimension to use the AGO, TODATE, and PERIODROLLING functions.

Note: A level-based measure is a column whose values are always calculated to a specific level of aggregation.

The calculation of this measure is independent of the query grain and used always the aggregation grain of the logical column.

Level-based measures allow :

* to return data at multiple levels of aggregation (the query grain and the level-based column grain) with one single query

* to create share measures (percentage), that are calculated by taking some measure and dividing it by a level-based measure. For example, you can divide salesperson revenue by regional revenue to calculate the share of the regional revenue each salesperson generates.

Web Catalog does contain object permissions: folder, reports, etc. The repository has objects permissions to Subject Areas, etc.