Re: Problem with bytea getBytes and setBytes

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От Xavier Poinsard
Тема Re: Problem with bytea getBytes and setBytes
Дата
Msg-id 3F85101F.5000707@openpricer.com
обсуждение исходный текст
Ответ на Re: Problem with bytea getBytes and setBytes  (Barry Lind <blind@xythos.com>)
Список pgsql-jdbc
Barry Lind wrote:
> Xavier,
>
> You don't mention what versions you are using, but I suspect you are
> using a 7.3 server.  If so this is a known bug in the 7.3 database.  The
> bug is that the server is incorrectly doing character set translation
> for binary values (i.e. the bytea data).  The work around for this bug
> is to set the character set of your database to UNICODE.  Unfortunately
> you can't change the character set after the database is created, so you
> will need to recreate your database.

You are right, I am using a 7.3.2 server and a 7.4beta4 jdbc driver.

>
> thanks,
> --Barry
>
>
> Xavier Poinsard wrote:
>
>> I am trying to use a bytea column to store binary data, but the getBytes
>> and setBytes methods aren't working as expected.
>> I suspect a strange escaping occuring.
>> I ran the following code :
>>
>> // insert test value
>> PreparedStatement stmtInsert connection.prepareStatement("insert into
>> test_blob (colblob) values(?)");
>> byte testBytes[] = new byte[255];
>> for (int i=0;i<255;i++)
>>    testBytes[i]=(byte)(i-128);
>> stmtInsert.setBytes(1,testBytes);
>> int count = stmtInsert.executeUpdate();
>> stmtInsert.close();
>> stmtInsert = null;
>>
>> // read and compare test value
>> PreparedStatement stmtSelect =connection.prepareStatement("select
>> colblob from test_blob");
>> ResultSet rs = stmtSelect.executeQuery();
>> while (rs.next()){
>>    byte resByte[]=rs.getBytes(1);
>>    for (int i=0;i<255;i++){
>>       if (resByte[i]!=testBytes[i])
>>          System.out.println("Problem with byte "+i + " "+resByte[i]+"
>> different from original " + testBytes[i] );
>>       }
>>    }
>> rs.close();
>>
>> The results (truncated) :
>> Problem with byte 32 -62 different from original -96
>> Problem with byte 33 -96 different from original -95
>> Problem with byte 34 -62 different from original -94
>> Problem with byte 35 -95 different from original -93
>> Problem with byte 36 -62 different from original -92
>> Problem with byte 37 -94 different from original -91
>> Problem with byte 38 -62 different from original -90
>> ...
>>
>> Xavier Poinsard.
>>
>>
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>
>
>
>
> ---------------------------(end of broadcast)---------------------------
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>


--
Xavier Poinsard  xavier.poinsard@openpricer.com
OpenPricer http://www.openpricer.com/
34, boulevard haussmann    75009 PARIS    FRANCE
tél: 33-(0)172712514


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