I have a scenario where a person/employee will take the survey by visiting a Eloqua landing page where the person will put his employee id and complete the survey but I have to prevent the person from taking the survey more than once. Is it possible in Eloqua?
Note: The person do not have email address only Employee id and we are not sending any emails as they have no email address.
Use JS to create a bogus email address to submit, with the Emp ID on the left hand side of the @, and use your internal domain (or a disposable address) for the right hand side.
Now regarding how to check if someone has already submitted the form, that will require some more coding on the front end and the use of either a field merge or data lookup - depending on if this survey is on an eloqua hosted page, and how the survey is built.