WMI DNS issue

[destinyml]

Hi

I'm making some queries to a DNS service with around 2000 zones. I would like to have a query to check if a zone is added to the server. I have made a query like the following:

Select * From MicrosoftDNS_ZONE where DNSServerName="xxx.xxxxxxx.xxx" and Name="xxxxxx.xxx"

The query is working fine, however it takes about 20 sec to execute. If I try to lookup a ARecord for example it take less than one sec:

Select * From MicrosoftDNS_ATYPE where DNSServerName="xxx.xxxxxxx.xxx" and OwnerName="xxx.xxxxxxx.xxx" and IPAddress="1.1.1.1"

Why is the zone lookup so slow, and is there anything I can do to speed up the query?

Thank you