On 22nd of August, Alvaro Herrera committed patch: Implement ALTER TABLE .. SET LOGGED / UNLOGGED This enables changing permanent (logged) tables to unlogged and vice-versa. (Docs for ALTER TABLE / SET TABLESPACE got shuffled in an order that hopefully makes more sense than the ...

On 29th of December, Robert Haas committed interesting patch, which does: Support unlogged tables.   The contents of an unlogged table aren't WAL-logged; thus, they are not available on standby servers and are truncated whenever the database system enters recovery. Indexes on unlogged tables ...