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Hi all, I am trying to get a Yes
- Thread starter Neoduder
- Start date
Hello Neoduder,
Here are the problems with the above scenario:
1) If the date never changes, then there is no reason to store the Y/N value because this would essential be a "calculated value", which could be determined on the fly at any time -- hence I is redundant.
2) If the date can change then you have the same problem, however this time you must ensure that the Y/N field gets updated at the same time, otherwise your data will not be correct. This is not a good situation.
3) If the date can change, but you only want to display the Y/N field to reflect the first date that the user ever enters into this field, then should be saving the dates in a history table. Otherwise nobody can trace back the Y/N value to see why it is 'Yes' or 'No'.
So, In the latter scenario you would not want to store the Y/N value because you can still calculate the Y/N result from the history table.
The best design practice dictates that you would not want to store this value.
Good Luck, Robert
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Professional, affordable, Access database solutions and assistance °•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°
Here are the problems with the above scenario:
1) If the date never changes, then there is no reason to store the Y/N value because this would essential be a "calculated value", which could be determined on the fly at any time -- hence I is redundant.
2) If the date can change then you have the same problem, however this time you must ensure that the Y/N field gets updated at the same time, otherwise your data will not be correct. This is not a good situation.
3) If the date can change, but you only want to display the Y/N field to reflect the first date that the user ever enters into this field, then should be saving the dates in a history table. Otherwise nobody can trace back the Y/N value to see why it is 'Yes' or 'No'.
So, In the latter scenario you would not want to store the Y/N value because you can still calculate the Y/N result from the history table.
The best design practice dictates that you would not want to store this value.
Good Luck, Robert
•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•
Professional, affordable, Access database solutions and assistance °•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°•°
- Thread starter
- #3
Cheers,
I think I got it working. The databse that I am designing is to store training records and I was needing the Yes/No field to show if the training had been completed or was still scheduled. I eventually got there by using a Query with a calculated field. Thanx for the help anyway though.
I think I got it working. The databse that I am designing is to store training records and I was needing the Yes/No field to show if the training had been completed or was still scheduled. I eventually got there by using a Query with a calculated field. Thanx for the help anyway though.
LittleSmudge
Programmer
So you are STILL storing redundent data in your table - as Robert pointed out in para 1 above it is a BAD idea.
G LS
accessaceNOJUNK@valleyalley.co.uk
Remove the NOJUNK to use.
G LS
accessaceNOJUNK@valleyalley.co.uk
Remove the NOJUNK to use.
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