This post may be helpful where I discuss a bit the difference between ‘client relevance’ and ‘session relevance’ Passing relay property to client in software deployment task
It looks like you’re mixing the two, and I’m not sure whether you’re trying to run this on the client (in an Analysis / Fixlet Debugger) or in a server session (Web Reports, Dashboard, REST API )
If you’re trying to run this on the client, the ‘fixlet’ type is more limited than in Session Relevance. There are no ‘fixlet flag’ or ‘category’ properties. What we do have on the client though are ‘headers of fixlet’ which we can use to apply the same kind of filters. In the Fixlet Debugger, this must be run in client context (Evaluate -> Evaluate Using -> Local Client):
q: number of relevant fixlets whose (value of header "X-Fixlet-Type" of it = "Fixlet" AND value of header "X-Fixlet-Category" of it is contained by set of ( "Security Update"; "Security Hotfix" ; "Critical Update")) of sites
A: 1
T: 0.033 ms
If you’re trying to do this in Session Relevance (API, Web Report, Dashboard, etc.) then we can use the ‘bes fixlet’ properties for ‘fixlet flag’ and ‘category’; but there is no ‘relevant fixlets’ property, because this queries against all computers and a fixlet may be relevant on one computer and not relevant on another; instead I’ll check for ‘exists applicable computers of it’. This query should work in a Web Report or REST query:
number of bes fixlets whose (fixlet flag of it and exists applicable computers of it and category of it is contained by set of ( "Security Update"; "Security Hotfix" ; "Critical Update"))