Three variables for Criteria

[lugnutmonkey]

I am wondering if it is possible to use three criterias (Representative ID, Month and Year) to make sure that I dont append duplicates into a table.

Essentailly I have a record where the combination of REP ID, Month and Year together should always be a unique combination. So by applying a criteria similar to this:

Query1.REP ID, Query1.Month], Query1.Year <> Table1.REP ID, Table1.Month, Table1.Year

Can anybody help me out with the code?

Or would I be better off using those three fields as a comibnation key in the table?

[orange]

In your table make a unique composite index of the 3 fields involved.
Access will give an error message probably 3022 if you try to add a duplicate.

None of the fields in the index can be null, you must have values for
REP ID, Month and Year

NOTE: You should not use a naming convention that allows spaces or special characters in field names.
Year and Month are RESERVED WORDS in Access.