I tried doing db.collection("posts").collection("comments").get() and db.collection("posts/comments").get() but neither seemed to work.

CodePudding user response：

Subcollections live under a specific document. In order to access the comments subcollection of a specific post, you'll need to specify that post ID in the path:

db.collection("posts").doc("post ID you want").collection("comments").get()

If you want to access documents across all comments collections, you'll want to use a collection group query:

db.collectionGroup("comments").get()