Hi, at SOTM '07 I discussed relations with a lot of people, and some said they think relation members should be ordered, like nodes are in a way. I maintained that that was unnecessary because if need be, you can always use the "role" to specify an order; and that's how it got implemented.
Meanwhile I think this was short-sighted of me; in numerous discussions people have demonstrated a need for (or at least: the usefulness of) ordered relations. One simple example is a bike/walking/bus route that has a little loop, formed like those "ribbons" you often see in signatures: _ < > X / \ Currently you can only specifiy the ways that are members of this, but you cannot specify in what order you have to follow them. I think we should switch to ordered relations. The way I would do this is not change anything in the XML, just add an extra "sequence" column to the relation membership table internally. Any old client would still work, but they'd have to be upgraded to make use of the ordering. We would prepare the migration and the next time we have some sort of downtime anyway, just pull it through. It would cost us a few more bytes in storage. Thoughts? Bye Frederik -- Frederik Ramm ## eMail [EMAIL PROTECTED] ## N49°00.09' E008°23.33' _______________________________________________ dev mailing list [email protected] http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/dev
