Add generic Quantile(n) function as an inversion of existing Percentile() function

Michal Zima

Description

Our business users are missing in DV (and also in "clasical" Answers tool) - thus generally BI Server list of aggregate function  - following function:

Function, which will calculate Quantiles. Currently there isnt such BI Server function available and the only way how to calculate it is to use EVALUATE_AGGR function with combination of Oracle Db function PERCENTILE_CONT.

So this new function would appear amongst other "Aggregate" functions and should provide results based on calculations below (taking from current calculation used):
Q(n): EVALUATE_AGGR('percentile_cont(n) within group (order by %1)', <attribute_value>), n <0, 1>
Examples:
Q(0.25): EVALUATE_AGGR('percentile_cont(0.25) within group (order by %1)', <attribute_value>)
Q(0.50): EVALUATE_AGGR('percentile_cont(0.50) within group (order by %1)', <attribute_value>)
Q(0.75): EVALUATE_AGGR('percentile_cont(0.75) within group (order by %1)', <attribute_value>)

 

Use Case and Business Need

Provide explicit quantile function (calculation) in DV/Answers to business users without a necessity to leverage/know Oracle db functions to perform the same.

Original Idea Number: b581784e1f