When append_optimized is enabled, incoming rows for AOTs first go to a special buffer. Once the buffer is full, Postgres Pro inserts these rows in a single operation whenever possible and generates a single WAL record for the rows. This reduces the time spent searching for buffers in shared memory and generates fewer WAL records.

A table with append_optimized enabled behaves like a regular table and supports all standard operations. An exclusive lock is required only when enabling or disabling the parameter on an existing table using ALTER TABLE ... SET.