Hi,

I think it's problem with implicit conversion. Could you please try to
fetch this blob with connection character set NONE?

regards
Pavel Cisar
IBPhoenix

Dne 6.4.2013 15:18, Hamish Moffatt napsal(a):

> Hi,
>
> I am using fdb 0.9.9 and Firebird 2.1 and I trying to fetch some data
> out of tables containing blobs. However the blobs I get back are always
> truncated at the first null.
>
>
> One such table is defined as
>
> SQL> show table g_mididrum;
> DRUM_NUMBER INTEGER Not Null
> DRUM_NAME (DOM_MIDI_NAME) VARCHAR(30) Nullable
> DRUM_WAVE BLOB segment 80, subtype BINARY
> CHARACTER SET NONE Nullable
> DRUM_WAVE_6 BLOB segment 80, subtype BINARY
> CHARACTER SET NONE Nullable
> DRUM_WAVE_12 BLOB segment 80, subtype BINARY
> CHARACTER SET NONE Nullable
> CONSTRAINT PK_G_MIDIDRUM:
> Primary key (DRUM_NUMBER)
>
> I'm making the query "SELECT * FROM G_MIDIDRUM". The cursor's
> description field after the query says
>
> (('DRUM_NUMBER', <type 'int'>, 11, 4, 0, 0, False), ('DRUM_NAME', <type
> 'str'>, 120, 120, 0, 0, True), ('DRUM_WAVE', <type 'str'>, 0, 8, 0, 0,
> True), ('DRUM_WAVE_6', <type 'str'>, 0, 8, 0, 0, True), ('DRUM_WAVE_12',
> <type 'str'>, 0, 8, 0, 0, True))
>
> The data in DRUM_WAVE (for example) is coming back as a string with
> len() of only 6 or 7 octets. However if I ask firebird to select the
> OCTET_LENGTH(DRUM_WAVE), it tells me the real length which are all 7000
> bytes up to >128k.
>
> I tried using stream blob mode on this column, I get a BlobReader, and
> when I read() all the data from it I still only get 6 or 7 octets.
>
> The connection charset is "UTF8".
>
> I got the same effect in kinterbasdb. We access this table from a C++/Qt
> app with the same query ok though. Can you point out my mistake?