Re: JDBC prepared insert and X00 and SQL_ASCII

On Wed, 18 Mar 2020 at 08:56, gmail Vladimir Koković <
vladimir(dot)kokovic(at)gmail(dot)com> wrote:

> Hi,
>
>
> After a thorough Java-Swig-libpq test, I can confirm that INSERT/SELECT is
> working properly:
> 1. server_encoding: SQL_ASCII
> 2. client_encoding: SQL_ASCII
> 3. INSERT / SELECT java string with x00
>
>
> libpq, psql - everything is OK !
>
>
> Vladimir Kokovic, DP senior (69)
> Serbia, Belgrade, March 18, 2020
> On 16.3.20. 17:04, gmail Vladimir Koković wrote:
>
> Hi,
>
> I don't know if this is a bug or the intended mode,
> but since ODBC works and JDBC does not, I would ask why JDBC prepared
> insert does not work if ODBC prepared insert works
> in case some varchar field contains 0x00 and DB is SQL_ASCII?
>
>
>
I responded on the github issue, but you cannot simply change the client
encoding for the JDBC driver. This is not allowed even though there is a
setting for allowClientEncodingChanges this is for specific purpose

*When using the V3 protocol the driver monitors changes in certain server
configuration parameters that should not be touched by end users.
The client_encoding setting is set by the driver and should not be altered.
If the driver detects a change it will abort the connection. There is one
legitimate exception to this behaviour though, using the COPY command on a
file residing on the server's filesystem. The only means of specifying the
encoding of this file is by altering the client_encoding setting. The JDBC
team considers this a failing of the COPY command and hopes to provide an
alternate means of specifying the encoding in the future, but for now there
is this URL parameter. Enable this only if you need to override the client
encoding when doing a copy.*

Dave Cramer
www.postgres.rocks