Enabling Watch API
However, Postgres and CockroachDB require special flags in order to enable the watch API, as they depend upon features not enabled by default in most installations.
To enable the Watch API on Postgres, it must be run with the Commit Timestamp tracking turned on:
postgres .... --track_commit_timestamp=on
To enable the Watch API on CockroachDB, it must be run with experimental changefeeds turned on.
See the CRDB documentation for how to enable and how to grant the proper privileges.