How to filter for documents with the same ID created within 3 seconds of each other

[ArmyGrooSMH]

I have unique files getting revisions.  Each file can have many revisions and I only care about the first two.

I have filtered the data so "docrevnum" is 0 or 1 .

What I would like to do from here is count the number of times those pairs have "docrevdate" within 3 seconds of each other.

Thank you,

ArmyGroo

[binuacs]

@ArmyGrooSMH What are the expected output results?

[ArmyGrooSMH]

The ideal output to the above is a count of the number of times "itemnum" shows a "docrevdate" within 3 seconds of each other.  The example data should show 6. 

There is one trick in the sample data. 

88343237

Shows up 3 times.  Twice with a docrevnum of 0.  This has been fixed on my side by adding a unique on docrevnum+itemnum+docrevdate.

I have 100million records and ideally want to know the number of times an item revision comes in within 3 seconds of the original.
I will be adding a groupby to the filetypenum after getting a count.