This feature is very useful for reservation forms or for checking the availability of a certain workshop. But it can also be used for an application form for a newsletter in order to verify whether the email address entered has been submitted before.
Alternative options
A limitation of this validation method is that you can only define one set of terms for every form. This means, for example, you can only validate a workshop’s availability for a single workshop. These types of validations can, however, also be performed in another, more flexible way. You can use the lookup feature to count how many times a specific answer has been given and the enhanced validations feature to ensure this number is within the accepted range.
Screenshots
Sample screenshots of the Duplicate Entry Validation feature
