Erland,

Thank you for replying. Basically the DB is for employee time
attendance records. I start out with a flat txt file and run that
through an Excel macro that:

a) eliminates repeat entries in a time lapse of 5min
b) erases null entries.

I then take the XLS file and use DTWizard to export it into a table
with the same fields as before: Date, Id, Time, IO. I have no primary
keys defined in this table, just a FK (Id). I believe the primary keys
should be ID, Date & Time.

I'll try your suggestion. Thx again, and sorry for the repeat post.