Time difference based on multiple records

[NeoPa]

Not at all. That's perfectly acceptable :-)

What you will need to decide though, because tables contain sets of data rather than a single ordered list, is which order you are referring to when you specify anything that is next or previous. In set terms those words are meaningless. A little like trying to quote area in meters. It's not possible because area is measured in square meters.

[rajeevs]

Not at all. That's perfectly acceptable :-)

What you will need to decide though, because tables contain sets of data rather than a single ordered list, is which order you are referring to when you specify anything that is next or previous. In set terms those words are meaningless. A little like trying to quote area in meters. It's not possible because area is measured in square meters.

Dear NeoPa
Thank you for the reply. The data will be ordered on the time field and records will be having IDs as well.
So it will be easy to refer to previous record either by ID or the order of time field

[NeoPa]

Are you thinking of updating the data in place or simply showing the amended data when querying the table?

[rajeevs]

Are you thinking of updating the data in place or simply showing the amended data when querying the table?

If coding is difficult a query with additionl field with the amended time will also help me

[NeoPa]

What are you actually after. I'm trying to avoid doing it twice. Both are possible.