[postgis-users] import raster

[Eloi Ribeiro]

On 2014-02-28 16:22, Pierre Racine wrote:
> Importing a big raster as a coverage with a huge number of small tiles
> always takes a long time. Two options:
> 
> -Increase the size of your tiles. They don't have to be that small to
> get good performance with intersections.

I just wont to make sure I have the fast result possible. This blog post 
[1] shows that for raster intersection with point features the small the 
tiles are the fast is the result.

> -Do you really need the raster to be inside the database? Try adding
> the -R raster2pgsql option. The import step will be way faster and up
> to now we haven't seen much difference in terms of
> intersection/extraction performance when the raster data is kept
> outside the db.

I have tested that. The result showed that the intersection of a 
imported raster with a point takes 12 milliseconds, while the same 
raster but register (in the file system) takes 36 seconds. I prefer to 
spend more time with import and then have faster intersections.

Eloi

[1] 
https://duncanjg.wordpress.com/2012/10/30/tile-size-for-raster-vector-overlays-in-postgis/