How to make consistent delete in Firebase database when the data lies in multiple paths in a fan out way? [duplicate]

Answer 1

You can implement a multi-path delete, by writing a value of null to the paths.

So:

var updates = {
  "user-posts/UserId1/PostId1": null,
  "post-comments/PostId1": null,
  "posts/PostId1": null
}
ref.update(updates);

I had already answered this before: Firebase -- Bulk delete child nodes

It's also quite explicitly mentioned in the documentation on deleting data:

You can also delete by specifying null as the value for another write operation such as set() or update(). You can use this technique with update() to delete multiple children in a single API call.