Calculate Mileage

[Bruce]

I am trying to calculate the mileage from two different fuel transactions.
The previous record has the mileage at the time of fueling and then the
subsequent record has the new mileage. How can I recall the previous mileage
to perform a calculation based upon the new mileage?

 

[Allen Browne]

Use a subquery to look up the value from the previous record.

Details and example in:
Subquery basics: Get the value in another record
at:
http://allenbrowne.com/subquery-01.html#AnotherRecord

 

[Bruce]

Allen,

Thank you for your reply. What I think is the best approach to this would be
to read the value from the prvious record. Do you have any examples of code
that I could use to reverse engineer this project?

 

[KARL DEWEY]

Post your table structure - field names with datatype - and sample data.

 

[Allen Browne]

Thank you for your reply. What I think is the best approach to this would
be
to read the value from the prvious record. Do you have any examples of
code
that I could use to reverse engineer this project?

Did you read example in the link I provided?

The link again:
http://allenbrowne.com/subquery-01.html#AnotherRecord

 

[Bruce]

Allen,

Thanks again for all of your help. I went back over the link you had sent me
and created a separate database and just walked myself through all of the
steps. Your help was and is most appreciated, an old dog has learned a new
trick, thanks again.