[OSM-dev] Mass imports (TIGER and AND)

[Martijn van Oosterhout]

On 8/29/07, Steve Coast <steve at asklater.com> wrote:
> Why is the transaction pointless? Isn't it _good_ that the entire
> call would succeed or fail?

Depends on the goal. If I have 100 updates which I don't know whether
they are going to work, then to get the whole thing uploaded will
require sending all the nodes each time there's a failure. It
basically means uploads of 50,000 nodes are not going to happen,
because of the almost 100% chance of failure.

Now if during the initial upload it returned a list of all the nodes
that wern't going to work, that means your down to only uploading
every node twice, which is better. The difference between that and
simply exiting on the first error (without rolling back the
transaction) is marginal.

For bulk uploads the goal is to upload as much as possible as quickly
as possible and ignore any errors (they'll be fixed by hand later).

Have  a nice day,
-- 
Martijn van Oosterhout <kleptog at gmail.com> http://svana.org/kleptog/