---> Simple question: once I execute the delete statement, does it free disk space immediatelly? No. deleted rows (in a sense) are simply marked as deleted and are made avaliable for being written over by a new or updated tuple. If you want to recover the space you can you TRUNCATE or VACUUM FULL & possible REINDEX.
Regards, Richard Broersma Jr. ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq