Ian Dees schrieb: > On Wed, Sep 16, 2009 at 9:30 AM, Tom Hughes <t...@compton.nu > <mailto:t...@compton.nu>> wrote: > > > This is NOT true. As I explained yesterday there is a very good reason > why we do not store a node revision in current_way_nodes and way_nodes. > > The problem is that if you do that then every time a node is changed you > have to go and find every way which uses that node and update it to use > the new version of the node. So it costs CPU time every time a node > is changed. > > > Can a way assume that it uses the most recent version of a node until > the way is changed? Then, when a way's revision number increments, all > of the rev#'s for the nodes that make up that way are saved along with > the way's history. But this wouldn't solve the problem of "give me all ways that used node #50, v3" as the last time way #10 was updated it only used node #50, v1 and so that's the last information that's saved.
Peter _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk
