[OSM-dev] [OSM-talk] donating read-only api-mirrors

[Matt Amos]

On Fri, Feb 6, 2009 at 11:47 PM, Stefan de Konink <stefan at konink.de> wrote:
> Matt Amos wrote:
>> On Fri, Feb 6, 2009 at 8:32 PM, Stefan de Konink <stefan at konink.de> wrote:
>>> Even then; the ordering can be done in SQL.
>>
>> not in the two-step scheme that Matthias was suggesting. it might be
>> possible using temporary tables, but care would be necessary to work
>> around mysql's horrible "can't re-open table" brokenness.
>
> I really don't see how you could fetch *all* ways without the nodes that are
> in the bbox or a join on the table.

what are you talking about? i was merely making the simple observation
that in the two-step node fetching scheme that Matthias was suggesting
(fetch and stream nodes in bbox, fetch and stream nodes used by way)
the fact that it is done in *two* queries with processing in-between
means it is impossible to order the results using only SQL.

the node IDs in the bbox and extras used in ways would have to be
merged and stored - which might be possible in a decent database - but
mysql has a limitation where it doesn't allow temporary tables to be
used twice in a statement, which makes things much more difficult.

>> adding an error element would require a (small) change to all clients
>> to support it, which is fine if all the tool authors are willing to
>> make the change (or accept a patch).
>
> Yes, but since we are changing protocols soon, error messages would be a
> minor implementation effort ;)

indeed. but the API 0.6 changes were agreed a long time ago. adding
even a "minor" change at this point would to be discussed and agreed
with the tool authors.

cheers,

matt