Protect from duplicate attendee records with multiple events

[Guest]

Can I check for duplicate entries while inputting new records in form? I am
using a slightly modified Event Management template from MSN online. Rather
than adding additional events to an existing attendee record, Access adds a
new record. Unfortunately, the appending tables route does not append the
subform info (the events previously attended). Any suggestions?

 

[Michel Walsh]

Hi,


If your table have an index not allowing duplicated value in a field, you
would get an error when trying to append that value.

If you want check BEFORE trying to save the record, you can compute the
DCOUNT returned about that value, like:

If 0 <> DCount( "*", "tablename", "numericalField=" &
numericalValue ) Then
... the numericalValue is already in the field
End If



Hoping it may help,
Vanderghast, Access MVP