> It was my understanding that a Blob Filter would process the data as it
> is written into the Blob, compress it or encode it, and then uncompress
> or unencode when the blob is read out.
>
> This is supposed to be a way to make sensitive data more secure, so that
> without the filter, a copy of the database would be of little use.

Do you allow anybody to copy the database ??
In that case I guess you allow to copy blob filter udf too,
and then such encryption has no sense.
(Unless you compile blob filter such that it runs only on specific computer.)

Ivan