A question of design

[CW]

Using Access 2003 I am creating an mdb to log companies' various certificates
and their renewal dates etc.
I have tblCompanies, with primary key on field CoID. This is linked
one-to-many with tblCertificates, which has foreign key CoID. It holds the
names of 8 different certificates which companies may or may not hold. As a
primary key it has CertID
which in turn links it to tblDates with foreign key CertID.
To input data I have a main form frmCompanies with tblCompanies as its
record source, then a subform sfrmCertificates using both tblCertificates and
tblDates as its record source. I have a combo enabling me to select one of
the certificates, and then a row of controls for the validity dates,
inspection dates and so on.
Problem: the only control I can use is the combo to select a certificate. As
soon as I try to edit any of the dates controls I get an error message saying
that cannot be edited or updated.
Where have I gone wrong in my design?
Many thanks
CW

 

[SuzyQ]

It seems you're missing a specific "certificate" table

tblCompanies
primary key
company name
other specific company info

tblCertificates
primary key
certificate name
other specific certificate infor

tblCompanyCertificates
foreign key to tblCompanies
foreign key to tblCertificates
date acquired
date expired
whate ever other information specific to company/certificate

form should be based on tblCompanyCertificates