Is there a good way to get around the list throttling threshold?
Here is my scenario: We have our top level site in a site collection with department sites beneath it. A few of the department sites are using a Task list. Originally, on the top level site, I created a page that had a few web parts on it that roll up all tasks for individuals who may be working in multiple areas (my tasks coming due in 2 weeks, my past due tasks, my deferred tasks, and my active tasks). All of these web parts are using the CQWP with some modifications to add a few more filters on it. It worked fine for a while until we went over our threshold of 5000 items. We do not want to increase this limit. I read that CQWP has some issues rendering on column that can't be indexed. I think the causing my issue is Assigned To (multi-select is not indexable). We do need the multi-select option.
Is there a better way to go around doing what I want to achieve? Either through a simple out-of-the-box solution or a third-party tool? I have to ability to edit the modify the additional filters on the web parts as well though Designer.
edit The CQWPs are looking at a specific site content type that is being used on these department task lists. For each CQWP, I have gone in and modified the filters using a CAML query, but none of them return information when they used to.