--- In IBObjects@yahoogroups.com, "Alan McDonald" <alan@...> wrote:

>
> > Hi,
> >
> > What i want is:
> > -automatically compress data when written to a specific blob
> > column via insert/update -automatically decompress data of a
> > blob column when selecting via a select statement
> >
> > What i did until now is:
> > -writing a dll which implements the blob filter (one for
> > compressing and one for decompressing) -put the dll in udf
> > folder of firebird (1.5.4) -registering the bob filter with
> > declare statement
> >
> > What i could'nt get to work is:
> > -invoking the filters via sql or ibobjects-api or firebird-api
> >
> > My questions:
> > 1) is there a way using blob filters in sql statements?
> > 2) how can i work with blob filters in ibobjects?
> > 3) can i use blob filters in stored procedures? if so: what
> > is the syntax?
> >
> > best regards
> >
> > falko :-)
>
> Have a look at the contributed code section at IBObjects website,
>there is a library there for the compression/decompression of blob
>data on the fly.
> It does not use filters but appears to do the job just as nicely.

I found ZipFilterBlob.zip. But thats not what i wanted. Its
client-side compression/decompression.

> From what I have read about filters, they are dificult to setup.

that's what i found out too :-(

>You need to declare a custom sub-type for blobs in the first >instance.

I did.

> Alan
>

Thanks Alan.
Seems that filters not used very often.

falko :-)