[sqlite] Reading strings and blobs

[Shawn Walker]

Is there a way to have sqlite to call a callback function to read in 
strings and blobs?  What I mean is that we have some very large data and 
rather not consume all those memory, so what I want to do is pass a user 
defined pointer that contains a pointer to a file handle (as an example) 
and that sqlite will call the callback function with the string/blob 
data and the callback function will write to the file.

Is that possible?