"Reuven M. Lerner" <reuven@lerner.co.il> Sunday 20 February 2011 12:31:09
> Hi, everyone. I've got a client who is planning to upgrade from
> PostgreSQL 8.3 to 9.0 in the coming weeks. They use a lot of tables
> with bytea columns. They're worried about the switch from octal to hex
> formats for bytea data.
>
>
> Based on everything I know and have read, the change is only for
> external representations, for input and output. Output is now by
> default in hex, but can be changed with a parameter (bytea_output) that
> provides backward compatibility. Input can be in either octal or hex,
> with no changes needed.
>
>
> My client is concerned that the internal representation has changed, and
> is asking me for a script that will change the representation, in order
> to save space (since hex occupies less space than octal). I'm not aware
> of such a need, or even the possibility for this to be done; even if the
> internal representation has changed, it'll be handled in the upgrade
> process, and doesn't need to be done with anything external.
>
>
> So I've told them that I don't think that anything is necessary for
> either input or output, except (perhaps) to set bytea_output in its
> backward-compatibility mode. But I wanted to check with people here,
> just to double-check my understanding.
>
>
> Thanks in advance,
>
>
> Reuven
There is no internal change how bytea is keept or at least internally data are
not keept in octal or hex represenation. If your client uses JDBC it's better
to download newest driver. It should support as well hex and octal receive. It
is safer to turn on backward compatibility. I know nothing how pg_dump will
work to migrate data.
Regards,
Radek