Hi there,
Having read many posts here regarding normalization, table designs with a view to avoiding duplication of data, avoiding storing of calculated contols into a field in a table (duplication as well as danger of keeping data updated, etc) - I would like to clarify something...
I've designed 2 databases, one sticking to the rules and one breaking them...
I hear the 'don't store' - calculate on demand principle - and this works well in the case of closing a new record where you 'store' a value by passing a subtotal from a subform to a field in the main form. All that passing of values works but there are time delays. Look at the time delay of summing a range of values in a form footer...bout half a second in general...So in this case, storing values fails...(incidentally is there an 'event' for this time delay a calculated control takes to show it's value in a form? - OnErrorCausedByDelayOfCalculatedControlToDisplayIt'sValue?? Oops ignore the apostrophe ;-).....).
On the other hand you may want to work through many thousands of records, summarising all your data into reports, charts, etc...It just seems that if you stored each records 'total' (say an invoice total) it would be quicker for to work through thousands of 'ready stored numbers' rather than thousands of 'calculations to get those numbers'...or maybe I'm missing something!?
Sorry for all the fuss, but I'm self taught and I wish I wasn't LOL. I shoulda definitely done college instead of getting hooked on databases in my 30's)
And I'm also sorry if this question has been asked before, even under different wording...
Best regards
dazza61
Having read many posts here regarding normalization, table designs with a view to avoiding duplication of data, avoiding storing of calculated contols into a field in a table (duplication as well as danger of keeping data updated, etc) - I would like to clarify something...
I've designed 2 databases, one sticking to the rules and one breaking them...
I hear the 'don't store' - calculate on demand principle - and this works well in the case of closing a new record where you 'store' a value by passing a subtotal from a subform to a field in the main form. All that passing of values works but there are time delays. Look at the time delay of summing a range of values in a form footer...bout half a second in general...So in this case, storing values fails...(incidentally is there an 'event' for this time delay a calculated control takes to show it's value in a form? - OnErrorCausedByDelayOfCalculatedControlToDisplayIt'sValue?? Oops ignore the apostrophe ;-).....).
On the other hand you may want to work through many thousands of records, summarising all your data into reports, charts, etc...It just seems that if you stored each records 'total' (say an invoice total) it would be quicker for to work through thousands of 'ready stored numbers' rather than thousands of 'calculations to get those numbers'...or maybe I'm missing something!?
Sorry for all the fuss, but I'm self taught and I wish I wasn't LOL. I shoulda definitely done college instead of getting hooked on databases in my 30's)
And I'm also sorry if this question has been asked before, even under different wording...
Best regards
dazza61
