Is collection query (single), faster than a groupCollection query?

Question

I have a collection group query for Posts subcollections (can be nested up to into 2 subcollections) ex.

firestore {
  users: <Collection> {
    posts: <subcollection> {... posts}
    types : <subcollection> {
     type1: <subcollection> : {
       posts: <subcollection> {... posts}
     } 
   }
}

For that i currently have a compound index and it is working well .

My question is, will be more performant to have 1 top level Collection Posts (denormalized with a cloud function) and query it instead?.

score 3 · Accepted Answer · answered Jul 02 '19 at 12:21

3

Collection group queries use fundamentally the same indexing strategy as normal queries, so they should operate with the same performance. Specifically, this means that the queries will scale with the size of the result set, not with the size of the collection(s).

answered Jul 02 '19 at 12:21

Doug Stevenson

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So in theory is the same you say – Yejiel Wahnich Jul 02 '19 at 12:36
You're free to run your own benchmarks to see if there is a practical difference. – Doug Stevenson Jul 02 '19 at 12:37
@YejielWahnich Did you end up running benchmarks yourself? I am facing the exact same problem as you (I also have a users collection and each user has a post sub-collection) – Yuval.R Jan 11 '23 at 15:38

Is collection query (single), faster than a groupCollection query?

1 Answers1