This articles is progress to write

Query feature

• Subcollectoin
  • If we use it, we cannot delete when delete root document.
• Query subcollection directly
  • If you want to query subcollection directly you can use Collection group queries
  • Subcollection query is as fast as root collection query

Can have 2000 fields in a document.

Articles

• Oficial best practice
• Working with Firestore: Building a simple database model

Videos

• Get to know Cloud Firestore | Youtube play list