There are certain fields that you never want to contain duplicate values. This might be a field containing the Employee ID or Invoice Number. You can prevent a field from having duplicate values by making it unique. In other words, for each record, the value in the field must be different.
A field can be marked as unique when it:
Doesn't contain a reference to the record ID#
Doesn't contain a reference to a dynamic function
Is not a list-user, list-text, phone, or address field
Follows the criteria listed in Limits in Quickbase
To require unique values in fields
You can require unique values using either field settings or Visual Builder.
Use field settings to require unique values
In the Basics section, select the Must be unique checkbox. You can also check for existing duplicate, non-unique values by selecting Check existing entries for duplicate values:
Select Save.
If you selected to check existing entries, a message appears if there are any duplicates and Must be unique is de-selected. You can:
Edit existing records to make corrections as necessary, return to the field properties page, then try steps 1-3 again.
Select only Must be unique if you decide it doesn't matter that existing data in this field is unique, or if you want only new entries in this field to be unique.
Use Visual Builder to require unique values
Open a table, select Settings, then select Structure. Visual Builder opens with the table expanded.
Select the field you want to appear in bold, then use the field properties on the right to select the Must be unique checkbox:
All changes are saved automatically.