We considered that but in the UK a postcode is limited to very few
households. The chance exists but is rare. I dont have any other fields that
can be part of a unique. I will go with the advice and keep this in mind.

Many thanks for your help.

James


"Lynn Trapp" wrote in message
...
In addition to what Nikos has said, you will probably want to reconsider
your plan a bit. Do you suppose that it's possible for 2, or more, John
Smiths to live in the same Postal Code? You could possibly encounter a
situation where 2, or more, John Smiths live at the same street address,
use
the same telephone number, etc. In most cases, it will take more than the
3
fields you suggested to guarantee a unique record.

--
Lynn Trapp
MS Access MVP
www.ltcomputerdesigns.com
Access Security: www.ltcomputerdesigns.com/Security.htm


"JBowler" wrote in message
...
Is it possible to make a combination of 3 fields be unique? I know you
can
have the ID (autonumber) be unique or have a field set to be indexed and
not
allow duplicates but I need to use 3 fields.

My scenario is a table (tblPeople) with Fname, Lname and postcode. I do
not
want any duplicate people in my tblPeople. They all have multiple linked
records in tblProjects. The problem is that someone doing data entry
keeps
creating duplicate people entries when they exist already. Can I set
these
3
to be unique together? Not as individual uniques.

Would it be easier to make a field in the tblPeople that is a
combination
of
Fname Lname Postcode and that be unique? Then on the form it would use
some
code to make the combination entered into that field. I could run a
query
to
make the 3000+ records have that combination field so its all up to
date.

What is my best approach? Any help or thoughts are appreciated. Many
thaks.

JBowler