Re: Toast and slice of toast

[Rémi Cura <remi.cura@xxxxxxxxx>]

Thanks everybody !

Cheers,

Rémi-C

2014-02-17 10:37 GMT+01:00 Andres Freund <andres@xxxxxxxxxxxxxxx>:

On 2014-02-17 14:16:33 +1100, Haribabu Kommi wrote:
> On Sun, Feb 16, 2014 at 9:38 PM, Rémi Cura <remi.cura@xxxxxxxxx> wrote:
>
> > Hey Dear List,
> > could somebody point me to some ressources about getting only parts of
> > toasted data?
> >
> > I have a very big custom type and I would like to take blocks of it (like
> > byte A to B then byte C to D  then... ).
> >

> > I found a function in http://doxygen.postgresql.org/tuptoaster_8c.html#called toast_fetch_datum_slice, is it the right way to use it

> > (a for loop and calling it several time?).
> >
>
> "pg_detoast_datum_slice" is the function which will solve your problem.

Note that you need to prevent your type/column from being compressed for
that being effective. Check the storage options for CREATE TABLE et al.

Greetings,

Andres Freund

--
 Andres Freund                     http://www.2ndQuadrant.com/
 PostgreSQL Development, 24x7 Support, Training & Services