In SQL, using Analytical function would meet requirement. Something as shown below 

value-lag(value) over (order by CollectionTime,metric)

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My problem is with assigning the value for Hash key defined as Time in this case, and then Subtract it from latest value to the oldest value.

No idea how to do it in perl, some hint or suggestions would be very helpful to me.

In reply to Re^2: Analytics on Hash Arrays by yasser8@gmail.com
in thread Analytics on Hash Arrays by yasser8@gmail.com

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