03-26-2015 06:10 AM
Godd morning all!
I have a VA Report in which I have lots of metrics grouped by Day, Hour and quarter of hour.
I neeed to compare the average of the values grouped by day with values of the previous day and calculate the delta.
Let's suppose that metric average for 24/03/2015 is 10, the metric average for 25/03/2015 is 30, I need to show a row in a table in which I have:
DELTA: 20 (30 - 10)
%DELTA: 66,67% [100*(30 - 10)/30]
If I could calculate easily VALUE_FOR_YESTERDAY I'll achieve the goal!
I try to use pre-defined functions like Difference for previous period using Date, by I suppose that I can use it only to compare one day with the previous Month...
Can you help me?
03-26-2015 08:56 AM
LAG function is something which refers to the previous row.
this gives you
Name Age New
A 20 .
B 50 30
C 40 10
And DIF is ,you can directly write the function DIF(age) you get the difference.
With Lag you can do any calculation with the previous row. and also with the previous row of any variable with the present row,