Modifying layers / in-memory layers

[Anthony Lenton]

Hello all,

Ok, here's a bit of a train of thought:

  I have been thinking that a very neat feature for thuban would be to
allow you to modify a layer's shapes and info some how.  For that a
previous step would be to have some sort of in-memory layers, to not
have to rewrite and reload a whole shapefile each time you modify
anything.  I looked in to this while coding the importMP extension and
I couldn't find in-memory shapestores.  The SHPTree class needs to be
initted from a shapefile.  I guess posgis shapestores could be used,
those are quite a bit faster than rewriting the whole shapefile, but
depend on you having postgis up and running.  There is an
implementation of an in-memory table, MemoryTable, but it doesn't seem
to be used anywhere, is this so?  And then there are also
TransientDatabase tables that use SQLite.

So,
 - What do you think of the whole
allow-the-user-to-modify-shapes-and-info idea?  Is it bound to fail?
Is somebody working on this already?
 - What do you think of the in-memory stores idea?  Is there an
implementation I haven't seen?  Is there a reason not to do this all
together?  Is a postgis store a better idea?
 - How much work does shptree do, is it a in-memory store that only
needs a shapefile to initialize from, or is it more of just a proxy to
the shapefile?
 - Has anybody tried SpatiaLite? http://www.gaia-gis.it/spatialite/ I
haven't, but it might come in handy as a middle point between keeping
layers in memory and needing to set up a postgis database.

Comments?  Ideas?  Suggestions?  Knights with rubber chickens?

-- 
Anthony Lenton
Except - The good guys in software development
http://except.com.ar