>>2) For quick access, relevant totals for each order should be stored in the order header.
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>Sorry to not agree on this point ... total can easily be calulated ! (especially when the price is in the detail lines :-)
I know they can be easily totalled. But what about the speed? In a similar system, I started calculating totals whenever they were needed. Since I found data access was too slow, I kept summaries up-to-date. Access speed became much quicker.
If this isn't currently a problem for you, well, just keep the data as it is.
You can also consider keeping a small "data warehouse": a version of data especially prepared for quick access to reports. This will have to be updated regularly with a program.
This will not only overcome potential limitations with your report system, but it may also make it easier for users to create personalized reports.
Hilmar.
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)
