Marc

I'll reiterate my earlier suggestion. Your design with repeating fields
(field groups - SampleN, CustomTariffN) is not well normalized. Removing
this information to a "child" table would allow you to better use Access'
functions and features.

One of the clues to the "one-to-many" nature of this relationship is in your
post wherein you stated that a customer (one) could have more than one
sample, with its related CustomTariff (many).

I also noted that you have a table with Customer information (apparently
name, address and fao), but that you also repeat those fields in your
tblDataEntry. Again, considering relational database design, this redundant
data storage is both unnecessary and it creates a situation in which you
must ensure the synchronization of the data between the two tables. If you
keep this design, you will need to handle the situation in which a
name/address/fao of a customer is changed in one table, but not the other --
now, which one is correct?! (the better design has this information
recorded only once, making that one instance the correct version)

I also noted that your tblDataEntry held NONE of the primary keys from the
related tables, only their text values. This presents the same issue
discussed above for the customer.

If you wish to further normalize your data structure, consider reading more
on the topic. The reason for having the related tables is so that you can
store the ID of the related table's value in your "one" table, not the text
of that related table.

--
Good luck

Jeff Boyce
Access MVP