Over the last couple of years, I’ve helped dozens of users and organizations to build Change Data Capture (CDC) pipelines for their Postgres databases. A key concern in that process is setting up and managing replication slots, which are Postgres' mechanism for making sure that any segments of the write-ahead log (WAL) of the database are kept around until they have been processed by registered replication consumers. When not being careful, a replication slot may cause unduly large amounts ...
