Avoiding duplicate contacts (unique field)

Hello,

I have a contacts table.  This table is open to everyone on the internet (within my company that can get behind the firewall but don't have a QB license).

It has contact types for relationship-based internal company fields that come from an HR database table and external company employee contact types that must manually be entered

• To show a single contact name and single contact email, I have a concatenate/text join formula field that uses an If statement and joins the last name, first name to give a consistent contact name when looking at the table and uses the internal email or the external email based on the type of contact

Problem:  I don't want users to be able to create duplicative contacts, which can be added from several different tables across different applications.  These contacts are related to a vendor table, projects table, etc (so we can associate contacts of all types with the different projects, vendors, and tasks across different applications). 

• I can make the external email required to be unique, but it seems I cannot make the internal lookup email field unique, which would allow users to add duplicative internal contacts.  And I cannot make the text join formula or formula based email field a unique required field either--says either formula field is not compatible with the make unique requirements.

Ideas for how to easily make it impossible to add duplicative contacts to the table?

Thanks in advance!



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Ryan Mcknight
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