Robert -- > >Ok thanks, > > >Is it dangerous to delete toast tables? >
Why would you want to ? They exist for a reason and are integral to postgres' design. That said, you can turn off TOAST, restart postgres and then a rewrite of the relevant rows will force the data to be "in-line" I think. Best to raise this issue on the posgres General or admin mail lists though. ... but again, there is a good rationale for TOAST tables (research the postgres documentation for your version and check the general mail list archives) and long varlena values, which a postGIS database can certainly have a lot of. The extra time in grabbing the compressed value from the TOAST table is far outweighed by the improvement in utilization of pages by rows of data. Greg Williamson > >________________________________ >Von: Greg Williamson <gwilliamso...@yahoo.com> >An: Robert Buckley <robertdbuck...@yahoo.com>; >"postgis-users@postgis.refractions.net" ><postgis-users@postgis.refractions.net>; PostGIS Users Discussion ><postgis-users@postgis.refractions.net> >Gesendet: 22:43 Donnerstag, 22.September 2011 >Betreff: Re: [postgis-users] where did pg_toast,pg_toast_temp1 come from? > >Rob -- > ><...> >> >>Thanks, >> >>my version is 8.4. The table contains strings but are not too long...under >>100char. >> >>Thanks, >> > > >According to <http://trac.osgeo.org/postgis/wiki/DevWikiPostGISCoding>: > >"All PostGIS objects are "varlena", they don't have a fixed size. ..." > >So maybe you got some large geometries that triggered TOAST processing ? > >Greg W. > >> >>________________________________ >>Von: Greg Williamson <gwilliamso...@yahoo.com> >>An: Robert Buckley <robertdbuck...@yahoo.com>; >>"postgis-users@postgis.refractions.net" >><postgis-users@postgis.refractions.net>; PostGIS Users Discussion >><postgis-users@postgis.refractions.net> >>Gesendet: 21:19 Donnerstag, 22.September 2011 >>Betreff: Re: [postgis-users] where did pg_toast,pg_toast_temp1 come from? >> >>Rob -- >> >>>Hi, >>> >>> >>>when I left work today these pg_toast tables were not in my database. when I >>>looked later ther were. >>> >>> >>>Can anyone tell me where they came from and why they are automatically created in every database? >>> >> >> >>You don't state what version of postgres this happens on, but in general >>TOAST tables are created by the system to hold long compressed values >>(typically text aka varlena tables). I think you can turn this facility off, >>but in general postgres will try to take very long strings, for example, and >>compress them, putting them into a toast table to that the row size of the >>original table doesn't grow excessively. See, for example, >> <http://www.postgresql.org/docs/9.0/interactive/storage-toast.html> >> >>So I suspect what happened is that someone entered some long text values and >>postgres created the toast tables to handle these long strings. >> >>HTH, >> >>Greg Williamson >> >> >> >>_______________________________________________ >>postgis-users mailing list >>postgis-users@postgis.refractions.net >>http://postgis.refractions.net/mailman/listinfo/postgis-users >> >> >>> > > > >_______________________________________________ >postgis-users mailing list >postgis-users@postgis.refractions.net >http://postgis.refractions.net/mailman/listinfo/postgis-users > > > _______________________________________________ postgis-users mailing list postgis-users@postgis.refractions.net http://postgis.refractions.net/mailman/listinfo/postgis-users
