Re: TOAST usage setting

Gregory Stark wrote:
> "Bruce Momjian" <bruce(at)momjian(dot)us> writes:
>
> > Gregory Stark wrote:
> >
> >> Is your database initialized with C locale? If so then length(text) is
> >> optimized to not have to detoast:
> >>
> >> if (pg_database_encoding_max_length() == 1)
> >> PG_RETURN_INT32(toast_raw_datum_size(str) - VARHDRSZ);
> >
> > Wow, we optimized length(). OK, will run the test with
> > substring(t,1,1).
>
> No, we did substring() too :)

Uh, I looked at text_substring(), and while there is an optimization to
do character counting for encoding length == 1, it is still accessing
the data.

--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://www.enterprisedb.com

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