Обсуждение: BUG #14064: Sort order of bytea, etc. not defined

The following bug has been logged on the website:

Bug reference:      14064
Logged by:          Chris Pacejo
Email address:      cpacejo@clearskydata.com
PostgreSQL version: 9.5.2
Operating system:   any
Description:

The documentation does not define (nor call out as undefined) the sort order
of bytea, bit varying, and other sequence types.  While the bytea sort order
is unsurprising (a < b if a is a prefix of b, but b > a if a prefix of b >
the same length prefix of a), it is not the only such "unsurprising" sort
order, and it would be helpful to have the guarantee that this sort order
can be relied upon (especially in concert with range types).

Hello, Cpacejo.

You wrote:

ccc> The following bug has been logged on the website:

ccc> Bug reference:      14064
ccc> Logged by:          Chris Pacejo
ccc> Email address:      cpacejo@clearskydata.com
ccc> PostgreSQL version: 9.5.2
ccc> Operating system:   any
ccc> Description:

ccc> The documentation does not define (nor call out as undefined) the sort order
ccc> of bytea, bit varying, and other sequence types.  While the bytea sort order
ccc> is unsurprising (a < b if a is a prefix of b, but b > a if a prefix of b >
ccc> the same length prefix of a), it is not the only such "unsurprising" sort
ccc> order, and it would be helpful to have the guarantee that this sort order
ccc> can be relied upon (especially in concert with range types).



You shouls use explicit type casting for such types.

--
With best wishes,
 Pavel                          mailto:pavel@gf.microolap.com

I'm not sure I understand? I know the data is bytea, how would casting it
to another type help? (I don't think casting bytea is even possible?)
On May 4, 2016 2:16 AM, "Pavel Golub" <pavel@microolap.com> wrote:

> Hello, Cpacejo.
>
> You wrote:
>
> ccc> The following bug has been logged on the website:
>
> ccc> Bug reference:      14064
> ccc> Logged by:          Chris Pacejo
> ccc> Email address:      cpacejo@clearskydata.com
> ccc> PostgreSQL version: 9.5.2
> ccc> Operating system:   any
> ccc> Description:
>
> ccc> The documentation does not define (nor call out as undefined) the
> sort order
> ccc> of bytea, bit varying, and other sequence types.  While the bytea
> sort order
> ccc> is unsurprising (a < b if a is a prefix of b, but b > a if a prefix
> of b >
> ccc> the same length prefix of a), it is not the only such "unsurprising"
> sort
> ccc> order, and it would be helpful to have the guarantee that this sort
> order
> ccc> can be relied upon (especially in concert with range types).
>
>
>
> You shouls use explicit type casting for such types.
>
> --
> With best wishes,
>  Pavel                          mailto:pavel@gf.microolap.com
>
>