I'm working on a SPA utilising BreezeJS and AngularJS, handling lots of entities (one of the types has ~60k entities). This is not an ordinary website, it's made for a specific purpose.
Most of the time the entities are shown in sortable, paged lists.
The above mentioned mass of entities gets cached and queried in a worker thread, so that the UI doesn't get blocked. We want to keep client-server communication to a minimum after application initialisation, hence the need for caching lots of data.
The results from the entityManager in the worker thread get imported to the entityManager in the UI thread and further processing follows. This all works fine, my only problem is that performing an orderBy on such a huge dataset takes too long for Breeze to complete (2.5-3.5 secs) without indexes.
This means that showing the next page is unacceptably slow if ordering is in place.
I could of course craft indexes for this particular model and amend the query to be run against the cache, but it wouldn't be easy to maintain, considering the dataset is allowed to change.
Breeze cache does not have indexes (indices?) today ... not even for the primary key. It would require a substantial increase in code base size and complexity to support them and we haven't felt that would be worthwhile for the workloads we usually see.
60K items clearly changes that equation.
I think indexing would be a cool optional module, a plugin of some sort. I don't think it would be that hard to maintain, given that the EntityManager raises events when anything changes in the cache. If you feel like taking it on as a community contribution ... perhaps to Breeze Labs, I'd be happy to advise and help a little.