On May 30, 2008, at 23:18, Thomas Wood wrote: > On Fri, May 30, 2008 at 9:21 PM, Stefan de Konink > <[EMAIL PROTECTED]> wrote: >> So would it be allowed to do: >> >> type=node ref=1 role=from >> type=node ref=2 role=at >> type=node ref=1 role=at >> type=node ref=3 role=to >> >> Or is the second 1 not allowed? >> > If by ref you mean node id, then yes, the second 1 is not allowed. > The API used to throw an unhandled exception back at you (500) if you > did it because of an index constraint on the database. > This has recently been fixed to actually return a nice error and stop > corrupting the database. (Although it may not have been deployed yet)
I'd hoped we only require the triple type/ref/role to occur at most once in a relation -- I'm sure there's some situations where one object logically fills two different roles in a relation. Examples: Modelling a u-turn-restriction with from,at,to roles, in which case from and to might be the same object. Start and End nodes in circular routes. Cheers Robert _______________________________________________ dev mailing list [email protected] http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/dev
