Yes, this is easy to do, but you will not be using Custom Data Validation.
A formula field can be flagged as being unique. That will mean that the system will not allow duplicates to be saved, the exception being that duplicate nulls are OK.
You will make a formula text field such as
List("-", [Field A], [field B], [Field C]) and flag it as being unique.
Note that these field may not be lookup fields. So if they are from a relationship, say from a table of Employees where the Key Field was [Record ID#], the formula would need to be
List("-", ToText([Related Employee]), [field B], [Field C])
and not
List("-", [Employee name lookup field], [field B], [Field C])
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Mark Shnier (YQC)
Quick Base Solution Provider
Your Quick Base Coach
http://QuickBaseCoach.commark.shnier@gmail.com
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