Richard Huxton wrote: > On Thursday 15 January 2004 14:17, David Garamond wrote: > > The MySQL manual recommends that we create a "fixed-length row" if > > possible, for speed (especially scanning speed). A fixed-length row is a > > row which is comprised of only fixed-length fields. A fixed-length field > > takes a fixed amount of bytes for storage (e.g. INT = 4 bytes, CHAR(M) = > > M bytes, etc). > > > > Is there a similar recommendation in PostgreSQL? I notice that most data > > types are stored in variable-length mode anyway (is cidr and inet data > > types fixed-length?) > > Not really - there have been various discussions about timing differences > between char() and varchar() and I don't recall one being noticably faster > than the others. > > > Is there a command/query in psql which can show storage requirement for > > each field? For example: > > No, but there's stuff in the archives, and I think something on techdocs too.
FAQ item 4.14 covers this, and reports CHAR() and VARCHAR() have the same performance characteristics. -- Bruce Momjian | http://candle.pha.pa.us [EMAIL PROTECTED] | (610) 359-1001 + If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania 19073 ---------------------------(end of broadcast)--------------------------- TIP 8: explain analyze is your friend
