Periodic SELECT queries seems like it would create big issues with transaction length for big enough tables (say ~1 billion rows and larger), because the transa

Periodic SELECT queries seems like it would create big issues with transaction length for big enough tables (say ~1 billion rows and larger), because the transaction stays open as long as the select query is not complete. This will definitely cause issues on busy tables. The operational aspects are pretty mild IMO, it's just another read replica from the view of the database. You indeed have to be careful with schema changes and admin, but that is something you already have to handle if you are running Flink. So I'd say that for big databases, CDC is not all that bad. And if your database is still small enough that you can get away with "SELECT *" a few times per day, why are you using Flink in the first place?