A Guide to Logical Replication and CDC in PostgreSQL with Airbyte

Logical replication in PostgreSQL is a method for synchronizing data across databases or between a PostgreSQL database and external data stores, leveraging the Write-Ahead Log (WAL) to track changes. This process can be configured to work at the transaction level, allowing for selective data replication. Unlike physical replication, which duplicates binary data at the byte level, logical replication offers more flexibility by enabling the selection of specific tables or rows for replication. The use of replication slots ensures data consistency across subscribers, with WAL records being retained until they are successfully published. Tools like Airbyte can facilitate the replication of PostgreSQL data to analytical environments such as BigQuery, Snowflake, or Redshift, through the use of source and destination connectors. Cloud-native platforms like Neon further enhance PostgreSQL deployments by offering managed scalability and features like database branching. Proper configuration of WAL settings, such as `wal_compression` and `max_wal_size`, can optimize disk space usage and improve performance, making PostgreSQL a versatile choice for various data replication needs.