How can I validate duplicates in Custom portlet

[Aj25]

Created a custom portlet for vaccinations and while testing we entered multiple identical vaccination types on the same date for the same employee and it went through without any warning or errors. 

what I want is it should not allow more than one record of the same vaccination type on the same date for a given employee. How this can be done? Thanks

[jsysel]

Hi,

there is no such functionality in SF (except national id validation) which can say this ID has been already used by different employee.

You can only build a rule that will use lookup to the same object and search for same date and employee ID...

Something like this:

JS

[Aj25]

Thanks Jsysel, Do you have any document to do that?