Calculation between two rows

[ahilsman]

I have a couple of questions.
I am using CR 11 and mySql DB.

I'm trying to calculate the elaped time between events for a simulator.

The elapsed time is the diffenece in time between records.

The Db stores the DateTime when the record was inserted as well as a projectID number. Two events, no matter what project they are for, can't go on at the same time.

Table: Log

Fields: logId as autonumber
ProjectId as integer
Time as DateTime

First when I sort the records by date in Acending order it does it correctly by date, but then it does it in decending order by time for each day? I have no idea why. I know MySql stores DateTimes as Strings.

Second my biggest problem is when I have to group the records by project then by month. How do I calculate the elapsed time since the records are no longer in order by time?

Thanks.

 

[Madawc]

Split time from date, and you should be able to control how they sort.

For calculating elapsed time, you'd probably need a subreport which views the record by time and does the calculation.

Subreports make a lot of work for computers, but save time for humans. You decide which is more important for your particular circumstances.

Madawc Williams (East Anglia, UK)