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alfor

Unrelated to the post:

Is there realtime features with postgres?

It seem like a kludge to have to add redis, mqtt, or kafka to our application to get things as they change.

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You can LISTEN/NOTIFY. Or you can use logical replication and a custom subscriber.[1] Supabase uses the latter.[2]

[1]: https://www.postgresql.org/docs/current/logical-replication....

[2]: https://github.com/supabase/realtime

we use this feature in Supabase, works great.

Supabase has arguably a better alternative, which uses logical replication and can be used outside of Supabase.

https://github.com/supabase/realtime

Supabase realtime (especially if you want a managed backend) or other streaming CDC setups (like Decodable, which is Flink/Debezium under the hood) are also great choices for logical replication. Streaming tech will continue to get more cost-effective and simpler to implement in the coming year(s).

I should note: I haven't used Decodable in production yet, I'm just a fan of Flink :)

One caveat about LISTEN/NOTIFY is that channels are not first-class objects, so there's no authorization associated with them, thus anyone who can login can also NOTIFY any payload to any channel.

There is NOTIFY [1] that might do what you are thinking of.

[1] https://www.postgresql.org/docs/current/sql-notify.html

Yes, WalEx.

Recently added the concepts of Destinations - where you can just configure it to send database change events to an Elixir module, webhook or EventRelay (the later two don't require Elixir know-how).

https://github.com/cpursley/walex?tab=readme-ov-file#destina...

Youre right, real-time is generally achieved by streaming CDC data with logical replication via a connector server to Kafka (Debezium does this) or a different queue to be picked up by consumers downstream.

Supabase does a great job of abstracting that part away with their real-time feature set

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