Re: Unlogged vs. In-Memory
Kevin Grittner <kevin.grittner@wicourts.gov>
From: "Kevin Grittner" <Kevin.Grittner@wicourts.gov>
To: "Magnus Hagander" <magnus@hagander.net>,
"Bruce Momjian" <bruce@momjian.us>
Cc: "Josh Berkus" <josh@agliodbs.com>, "PostgreSQL Advocacy" <pgsql-advocacy@postgresql.org>
Date: 2011-05-13T21:04:42Z
Lists: pgsql-hackers
Bruce Momjian <bruce@momjian.us> wrote: > I thought global temp tables were tables that existed as empty in > every session and had per-session data. Yeah -- they're not the *same* as unlogged tables. What makes it *similar* to me is that there is one definition visible to all sessions, changes are not logged, and data is not necessarily written to disk during normal operations, and on a crash all data is lost. The differences are that with unlogged tables all sessions share the same data whereas with global temporary tables each session has its own set of data, and on clean shutdown the unlogged table will be saved for reload on startup. -Kevin