Ivan Prenosil schrieb:

>>Did I misunderstand something there? I thought that blob filters were
>>implicitly invoked when dealing with columns oder PSQL variables of
>>different blob subtypes, e.g.
>>
>>FOR
>>SELECT tif_blob
>> FROM pic_table
>> INTO :jpg_var
>>DO...
>>in a SP (with a corresponding filter declarde)
>>???
>
>
> No, this will not invoke blob filter. (unless somebody implemented it
> in the latest version and did not tell to others ...)
>
> The only way is using BPB when opening blob from client ...
>
> Ivan
> http://www.volny.cz/iprenosil/interbase/
>

"The Firebird Book" (p.771) states that after declaration of a filter
"in your SQL or PSQL, all you need to invoke the conversion
automatically is a variable or database column, declared as BLOB
SUB_TYPE xx ... and a destination variable or column of SUB_TYPE
yy to receive the converted document." (xx and yy being the SUB_TYPES
the filter is declared for.

What's correct then?
I can't try without a working filter. And I won't learn to write a
filter when I can't use it...

Urs