Is there a way of stopping repeating records in an append query???

costomer can't do more than 1 purchase prob;

make a purchase tables; with a purchase id;

relate this with the customer id....

when the key field is set to customer and
purchase id; i ment.....

I hope it works...

I tried this, but i cannot enforce the link between customer ID and purchase ID.

why not??

Data in 'Customertbl' violates referential integretity rules!

That's a problem with the join in the relationship. Go to the relationship tab at the top of dB window. There is an option to "Enforce Referential Integrity" if you uncheck that box, it should help.

Dont I need to enforce the relationship for it to work though?

I tried it without it and when i opened it after entering some data, there were numerous numbers of duplicate records.

When you use referential integrity, you tell access that record #1 in Table A must have a related record in Table B. What this does for you is prevents related records from being deleted. For instance, you would not want to have a customer Id in Table A with no Order in Table B.
Have you tried using the help files yet? I found them to be most helpful when I was starting out.