-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 10/02/06 16:19, Tom Lane wrote: > Alexander Staubo <alex@xxxxxxxxxxxxxxx> writes: >> You could count the disk space usage of the actual stored tuples, >> though this will necessarily be inexact: >> http://www.postgresql.org/docs/8.1/static/diskusage.html >> Or you could count the size of the physical database files (/var/lib/ >> postgresql or wherever). While these would be estimates, you could at >> least guarantee that the dump would not *exceed* the esimtate. > > You could guarantee no such thing; consider compression of TOAST values. > Even for uncompressed data, datatypes such as int and float can easily > print as more bytes than they occupy on-disk. > > Given all the non-data overhead involved (eg for indexes), it's probably > unlikely that a text dump would exceed the "du" size of the database, > but it's far from "guaranteed". It's my experience that when there are lots of numeric fields, fixed-width text records are approx 2.5x larger than the original binary records. - -- Ron Johnson, Jr. Jefferson LA USA Is "common sense" really valid? For example, it is "common sense" to white-power racists that whites are superior to blacks, and that those with brown skins are mud people. However, that "common sense" is obviously wrong. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (GNU/Linux) iD8DBQFFIZgvS9HxQb37XmcRAp6xAKC74LV+2wR6Ao5Oq56RInkkDP8PZgCglKEv z0fvjrXTloWJJ7qdhfOpIoI= =jICB -----END PGP SIGNATURE-----
