Custom objects

all the subcolletions must have the same name, for instance tags

if you only need to display the tags of a single question, use the first schema. If you want somehow to display all the tags of all questions, the second schema is recommended

Security rules apply only at the matched path, so the access controls defined on the cities collection do not apply to the landmarks subcollection. Instead, write explicit rules to control access to subcollections

Duplicated data is a common practice when working with non-relational databases as Firebase. It saves us from performing extra queries to get data making data retrieval faster and easier

normalizing our dabatase will help us. What means normalize? Well, it simply means to separate our information as much as we can

Documents in Cloud Firestore should be lightweight, and a chat room could contain a large number of messages

In Cloud Firestore, the unit of storage is the document. A document is a lightweight record that contains fields, which map to values. Each document is identified by a name.

Cloud Firestore's NoSQL data model, you store data in documents that contain fields mapping to values

can also think of collections similarly to tables in a SQL Database

we’re going to use cloud firestore because it’s easier to work with and more versatile

Firebase Database (Real-time database or Firestore)