[Tile-serving] [osm2pgsql] Good cheaper indexing (#171)

[Paul Norman]

> I did some tiles following the switch2osm script and it was quite slow as there was no indexing on the db. It would be 'nice to have' help indexing the db for beginners.

There are spatial indexes created by default with osm2pgsql, as I indicated above. If you didn't get indexing, you probably interrupted the process and got an incomplete import

> I found the code that triggers the spatial indexing in mapnik,

Strictly speaking, it adds a spatial constraint. Index usage is up to the postgresql query planner, not mapnik. It may or may not use spatial indexing, and in many cases won't use spatial indexing for low zooms where it would be slower than sequential scanning.

Anyways, I don't see anything here that would be an improvement over standard methods.

---
Reply to this email directly or view it on GitHub:
https://github.com/openstreetmap/osm2pgsql/issues/171#issuecomment-52716877
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/tile-serving/attachments/20140819/188c64b4/attachment.html>