Buried in the very long (and somewhat intimidating) Search Overview page is this line:
An empty string value should be used when searching for objects with a null value for the specified filter. For example, to find all objects without a template defined use Template:'' in the query.
This suggests you could use: Parent:''
However, since an event frame without a parent would be at the topmost level of the database, and you don't want to consider any child event frames, you could alternatively use this filter instead of Parent: AllDescendants:False
I have no numbers to suggest one is better than the other, so if you are willing to test it out and get back to us, I would be most grateful. If they performed the same, I would stick with the Parent filter since it clearly shows your intent.
The Parent:'' syntax throws an exception: 'The search criteria 'Parent:""' is not valid for Event Frame search.'
I tried the AllDescendents:False, however it is returning Event Frames that have parents. Notably, on stepping through the code, I find Event Frames where:
- the Parent field is null
- the Parents array shows a count
- the ParentID shows a guid.
Not sure what to make of that...
You are using AF Client 2.10 and the Parent filter is allowed for Event Frame searches since 2.9.5. This suggests to me that your AF Server is older than 2.9.5. Can you tell us the AF server version? Search capabilities are determined by the lower of the Client and Server versions.
Aah Yes. We are using an older version of the AF Server - 2.9.1.