How do you enforce at the table level uniqueness over tow fields in the same table? The Unique check box under the Validation tab is for the current field. But I need it to be over two fields.

Do you mean that the value can only be used one time in either of the fields? In other words, if you type the word "blue" into any record in either one of the fields, you do not want the user to be able to type "blue" into either field for any record again. If so, what is the purpose of doing this?

See if this helps.

No, I mean where the combination of the two fields is unique for the table. Eg. Field A and Field B may have the following values:

blue, cat

red, dog

green, bird

red, bird

the above are all unique. But repeating any of the records would be non-unique.

yes it does. thanks so much. I have chosen the method of creating an extra field in the table, using auto-calc to concatenate the two fields, then under validation tab, ticking the unique box for this auto-entry field.

Being a newbie to FM, but an old hat at SQL, its a paradigm shift for me. Eg in any SQL language I know (Oracle, DB2, MySQL and even Access), you never need to create an extra field in order to achieve uniqueness - hence the reason why I did not think along this line). But I am slowly coming to speed on the FM way of thinking :)