Gregory Stark wrote: > Tom Lane <[EMAIL PROTECTED]> writes: > > > Bruce Momjian <[EMAIL PROTECTED]> writes: > > > Tom Lane wrote: > > >> Either way, I think it would be interesting to consider > > >> > > >> (a) length word either one or two bytes, not four. You can't need more > > >> than 2 bytes for a datum that fits in a disk page ... > > > > > That is an interesting observation, though could compressed inline > > > values exceed two bytes? > > > > After expansion, perhaps, but it's the on-disk footprint that concerns > > us here. > > I'm a bit confused by this and how it would be handled in your sketch. I > assumed we needed a bit pattern dedicated to 4-byte length headers because > even though it would never occur on disk it would be necessary to for the > uncompressed and/or detoasted data.
Well, we have to expand the TOAST anyway in memory, so when we do that we already give it the right length header. -- Bruce Momjian [EMAIL PROTECTED] EnterpriseDB http://www.enterprisedb.com + If your life is a hard drive, Christ can be your backup. + ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org
