Re: casefile random access

[John Darrington]

On Tue, Jun 06, 2006 at 06:49:11PM -0700, Ben Pfaff wrote:
     John Darrington <address@hidden> writes:
     
     >      Perhaps I will reconsider the approach, then, in the end.  But
     >      it's worth checking it in for now, I think.
     >
     > I think that's probably the best idea.  I started thinking a little
     > more deeply about integrating casefiles into psppire-data-store.c, and
     > I've now got a lot more questions than answers.   So I suppose it's
     > time to dive in and get a much better idea of the situation --- and
     > then consider the next move ...
     
     Now checked in.

Great.  The only problem is, that the comment at the top of the file
which says that casereaders cannot randomly seek, is no longer true.

I had a look at the GUI again last night.  A number of problems are
beginning to come apparent.  One is the issue of inserting/deleting
cases in the middle of a casefile; I don't think it's possible.  I'm
thinking of  having some kind of auxiliary structure to store
inserted/deleted cases. Or perhaps casefiles can be extended to allow
us to do that?

Another issue, is that casefiles have a fixed value_cnt, which makes
inserting/deleting variables difficult.  I think the way around this
problem is to run a procedure whenever the dictionary is changed. 

J'

-- 
PGP Public key ID: 1024D/2DE827B3 
fingerprint = 8797 A26D 0854 2EAB 0285  A290 8A67 719C 2DE8 27B3
See http://pgp.mit.edu or any PGP keyserver for public key.

signature.asc
Description: Digital signature