Work out the total time that something has happened for

[Gareth Knopp 2]

Hi,

I have a Data table with multiple different vehicles (Serial Number - SN) in it, with data points on a specific DateTime. So the unique identifier is DateTime & SN. I'm trying to find a way to work out the number of minutes/amount of time that something happens for.

So, for example, a setting or flag is recorded when an event occurs, that record has a time stamp, I want to compare to the previous entry timestamp, work out the difference between them and display this in minutes!

I created a TimeSpan Column of the DateTime column

TimeSpan([DateTime])

Then I looked at using the OVER function:

[Time_Span] - Min([Time_Span]) OVER (Previous([DateTime]))

But this doesn't really seem to work!

[Richard Pobi]

If the SN is also a primary key/unique identifier then use the SN instead of the datetime.

[Time_Span] - Min([Time_Span]) OVER (Previous([sN]))

[Richard Pobi]

If SN & DateTime falls under one column. eg. Column1 then use it for the OVER function

 

[Time_Span] - Min([Time_Span]) OVER (Previous([Column1]))

 

If they are two different columns then add it to the expression. 

 

[Time_Span] - Min([Time_Span]) OVER (Previous([sN]), (DateTime))

 

Check the link below for help

https://docs.tibco.com/pub/sfire-bauthor/7.8.0/doc/html/en-US/GUID-35B6C76C-EF02-49BF-9A34-EBEB20434ACC.html

[Gareth Knopp 2]

Hi richierich,

 

The Unique ID is a combination of two columns. - SN & TimeDate - but I am getting errors, with the above formula.

 

[Time_Span] - Min([Time_Span]) OVER (Previous([Asset]), (DateTime))

 

Spotfire is not happy with the ',' after [Asset]

 

[[{"fid":"164321","view_mode":"default","fields":{"format":"default","field_file_image_alt_text[und][0][value]":false,"field_file_image_title_text[und][0][value]":false,"height":"","width":""},"type":"media","field_deltas":{"1":{"format":"default","field_file_image_alt_text[und][0][value]":false,"field_file_image_title_text[und][0][value]":false,"height":"","width":""}},"attributes":{"class":"media-element file-default","data-delta":"1"}}]]

 

I should add that the reason these are formatted this way is that each vehicle creates its own record which is the input for the master table, so each asset does not have a unique Data Table.

 

Thanks,

 

Gareth