Should splitting raster files into tiles increase query performance?
I have a two 1201x1201 raster tiles that were loaded by the following
scripts:
raster2pgsql.py -a -r N37E126.hgt -F N37E126 -t srtm3 -s 4326
*-k1201x1201* > srtm.sql
psql -f srtm.sql TEST
raster2pgsql.py -a -r N37E127.hgt -F N37E127 -t srtm3 -s 4327 *-k50x50*
> srtm.sql
psql -f srtm.sql TEST
Querying these raster files appears to produce approximately the same
timing results. Should the 50x50 have better performance than the
1201x1201? Taking almost 3 minutes to query 10000 points seems to be
very slow.
Number of Lat/Lon Pairs Time in secs for
1201x1201 Time in secs for 50x50
1000 17 sec
20 sec
5000 85 sec
104 sec
10000 167 sec
205 sec
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