Hi,
Our users enter a list of catalog numbers and indicators in the
spreadsheet on column A and B. I need to loop through each row and
query each pair of catalog numbers and indicators against an Informix
table to verify that these values exist (i.e., the user didn't
accidentally enter some wrong values).

The SQL will be something like this:
select count(*) from books where cat_number = ? and indicator = ?;

If the SQL returns a row, then the cell values are valid.

I'm new to VBA so I can write simple stuff but I am too familiar with
the ADO model.
Any assistance is much appreciated.
Thanks.