I am using a custom object which is a child of the account object.

If I run this query:

Select a.Name, (Select Partner_Research_Name__c, Partner_Research_URL__c From Partner_Research_Records__r) From Account a

I get a list of all accounts some of which contain a record Partner_Research_Records__r that is blank, and others (when the object is present in the parent object) a set of values.

I want to add something to the where clause that will filter out any responses where the Partner_Research_Records__r recordset is null, however I can't seem to figure out the proper syntax.