Hello!
I've the following data:
datetime | val1 | val2
time1 | 4 | 40%
time2 | 7 | 30%
time3 | 12 | 20%
...
I'd like to sum up the following:
(7-4)*30% + (12-7)*20% + ...
datetime is ordered (and unique and has also an id).
Rows are in the area of millions.
How is it done best?
1.) Self join with one row shift?
2.) function?
Any hint?
Thnx.
Ciao,
Gerhard
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