Why database engine should know all about format of data it stores and have all of it as a single number?
(BTW Is jpeg2000 still a jpeg ? Several versions of gif format...)
Could be such code for some classes of data (text/binary/code/database) but not just each type/subtype I suppose.
Maybe it is a good idea in using of so called MIME type encoding (based on a text strings: text/html, image/jpeg, application/data etc
with adddition to encoding etc Like it is in mail or http protocols. Lets call it blob identification block and store with blob data) or register a separate blob type - MIME data...
Could be at least possible to have standart table to convert blob code to mime type.

The general purpose of filter is to get a plain text in right encoding from other kind of text data. I could not believe if somebody will benefit from convert jpeg to gif or tar to bzip using database. Anyway, there is nothing wrong in dinamical registration of filters by mime types as external modules/applications not just by codes inside engine I think.

Maxim Sinev
Spektrum Web Development
http://www.spektrum.org.ru

> At 03:51 PM 5/9/00 -0300, Marcelo Lopez Ruiz wrote:
> >> Shall we consider adding the following:
> >>
> >> #define isc_blob_jpeg 25
> >> #define isc_blob_gif 26
> >> #define isc_blob_rtf 27
> >> #define isc_blob_xml -400
> >> #define isc_blob_html 28
> >> #define isc_blob_wav 29
> >> #define isc_blob_mp3 30
> >
> >What about...
> >#define isc_blob_ico 31 Windows icon files
> >#define isc_blob_gdb 32 InterBase database file
> >#define isc_blob_dfm 33 Delphi Form file
> >#define isc_blob_bsh 34 Script file
> >?
> >
>
>
> An Inerbase database file isn't a well defined format in the
> sense that it's a moving target. Also, from an architecture
> point of view, nothing but the engine and possibly a low level
> maintenance utility should ever be aware of the format. Developers
> are, of course, exempted.
>
> Is there a definitive specification of a Delphi Form File? A fixed
> specification is a necessary prerequisive to a subtype number.
>
> Jim Starkey