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PRIMARY KEYS
Resolved · Urgent Priority · Version 2007
Reply Tue 24 Feb 2009, 16:41Delegate George said...
George has attended:
Access Intermediate course
Access Intermediate course
PRIMARY KEYS
WHEN WOULD YOU USE MULTIPLE PRIMARY KEYS AND GIVE EXAMPLES
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RE: PRIMARY KEYS
Hi George
Thank you for your question
Multiple or compound keys are used in place of an autonumber field, where there is no one existing field that is unique to individual records.
For example if you had a staff database with no unique fields you might decide to use a key compounded out of first name, second name and date of birth fields
The important consideration would be the uniquness of each combination. In the above example the developer would have to consider the likelihood of two people sharing the same first and second names as well as a date of birth
Hope this helps
Regards
Stephen
Thu 5 Mar 2009: Automatically marked as resolved.
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