nodejs-firestore
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googleapis
Eager loading Document References
Hey,
It would be very handy to be able to eager load Document References as objects. Is this something you have considered?
Thanks anyways :P
Hi @Tyranwyn! Can you elaborate a little more what your use case is? If you are interested in pre-fetching of documents, then you will likely want to use one of our clients that supports offline persistence (such as our Mobile Web client). The Server SDKs do not cache any data.
That being said, you will have to pre-fetch documents manually in the Mobile SDKs as well. If you would like us to add this as a top-level feature, you can find out team at https://github.com/firebase/firebase-js-sdk
Thanks!
Oh, thanks for your quick reply. I have modelled the database so that some objects contain references to other objects, and it would be awesome to have an option to get the referenced objects themselves instead of just references. Im displaying a list of "Employees" and they reference to an array of "Project" objects. Now I have to loop over all the employees, and then loop over the array to get all project objects. It would be easier (and more efficient?) to get these projects as an object stored in the array of the employee.
I hope this is not too confusing? Also, this probably needs to be implemented client-side aswell as server-side? Tell me if I'm wrong.
Thanks!
Oh, interesting. That's a feature request we don't yet have on our roadmap. I can't promise that we will get to it soon, but we will discuss this internally and see if it makes sense to expose it in all of our clients.
I would love something like this too! Perhaps something like the Eager Loading Syntax for Rails? It would be great for minimizing N+1 queries.
A first step might be if it were possible to efficiently support Logical OR queries and to have syntax that allows you to pass in an array for matching anything in that array, e.g. where('projectId', 'IN', [1,4,10,15,20]). Then the client could do the eager loading themselves.
I played around with this a bit the other day, and I think you can do this yourself with the existing client. Here is a gist I made illustrating how I did it.
Granted it's more than one line, but it also gives you more control of the traversal and fine grained error handling/recovery options.
Given that firestore is a collection oriented document store, it isn't really in the same area as relational databases in terms of providing support for joins.
We would need some more user feedback before scheduling this work.