I understand, but in this case, since the option is offered next to the safe one, most people won't know it isn't safe. I certainly didn't until I read this posting. I know generally what vacuuming does, but I had no idea that postgres offered a potentially damaging option. Also, PgAdmin sometimes tells me that a table needs vacuuming, so it is already "advising" people in that area ...
On Fri, Dec 3, 2010 at 9:19 AM, Guillaume Lelarge <guilla...@lelarge.info>wrote: > Le 03/12/2010 15:17, Michael Shapiro a écrit : > > The document http://wiki.postgresql.org/wiki/VACUUM_FULL says: > > > > VACUUM FULL, unlike VACUUM, tuples data that has not been deleted, moving > it > > into spaces earlier in the file that have been freed. Once it's created a > > free space at the end of the file, it truncates the file so that the OS > > knows that space is free and may be reused for other things. Moving > in-use > > data around this way has some major downsides and side-effects, > especially > > the way VACUUM FULL does it. There are better ways to free space if you > need > > to and better ways to optimize tables (see below) so *you should > essentially > > never use VACUUM FULL*. > > > > > > PgAdmin does not give the user a comparable warning when it goes to > execute > > a VACCUM FULL. Given the potential problems with the FULL option, would > it > > make sense for PgAdmin to issue a warning to this effect? > > > > I'm not sure this is the role of pgAdmin to warn people they are doing > potentially stupid things. > > > -- > Guillaume > http://www.postgresql.fr > http://dalibo.com >
