[manigandham]

Why would a SQL query show stale data? Inserts and selects are fine, the only thing needed is signaling. You can use Firestore for that, or just a separate thin layer on a much more capable database backend.

> "that few development teams have the skill"

This is the fundamental problem. There's no magic answer to a lack of skill.

[mhoad]

Because the way that you will ultimately have to scale something like PostgreSQL for example is going to end up with eventual consistency which Firestore doesn’t have to deal with.

[manigandham]

There's no reason for eventual consistency. Firestore is backed by BigTable and Spanner (both strongly consistent just like Postgresql). There's nothing magic about this - it just provide a pub/sub channel on the watched keys and automatically does a SELECT loop in the background once an INSERT triggers that key.

You can do the same thing on a simple by selecting by a `chatid` in a table that'll get the latest messages/inserts. Again, the only thing needed is the pub/sub layer, not an entirely different database.