I need to compare two field values.
Let's say I have a content type named "Specimen". The content title is the accepted name of that specimen. A second field, named Synonyms, can be filled by users to suggest synonyms for the accepted name.
What I need is a field validation with that kind of test : If the synonym matches any title of that content type, then display a message (That synonym is actually an accepted name already entered in the database) and invalidate the value entered. Else, the synonym is valid and can be entered in the form.
I know Uniqueness which is a great module to compare titles between them but not between a CCK Field and each title (unless I missed something?)
I have tried to configure a test with the module Field validation but did not manage to get a nice result, even with the test "Match against a field". Maybe it was not set properly.
I guess that Rules can be my friend too but for now, I have always created very simple rules. So I would appreciate any help to build this test.