yes you are right, there are some limitation to fetch xml.
you cannot use and/or operator when comparing different entities but you can when you are comapring the attributes of same entity
<filtertype='or'><conditionattribute='gradefilter'operator='eq'value='0'/><filtertype='and'><conditionattribute='minimumgrade'operator='ge'value='1'/><conditionattribute='maximumgrade'operator='le'value='12'/></filter></filter>
If you are trying to use reports then you can use filtered views to create sql queries.
it is only possible for on premise deplyment.
I hope this helps.
If you find this post helpful then please "Vote as Helpful" and "Mark As Answer". Amreek Singh Senior CRM Consultant CDC Praxa Sydney, Australia
http://mscrmshop.blogspot.com
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