We will cover how to split your database across devices. Including backup, restoration, streaming replication and other gotchas.
Example 1: Splitting data between unencrypted and encrypted devices to encrypt PII for have performance with data that does not contain PII data.
Example 2: Splitting data between local and network storage. Using your network storage or archived, read only, data that you don't need the highest performance but still want to join to your current data.
Example 3: As you know, Postgres double writes everything, WAL and Data files, plus the logs files, makes triple writes. Splitting your Data, WAL Files, and Log Files to separate devices for performance.