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Should splitting raster files into tiles increase query performance?<br>
<br>
I have a two 1201x1201 raster tiles that were loaded by the following
scripts:<br>
<br>
raster2pgsql.py -a -r N37E126.hgt -F N37E126 -t srtm3 -s 4326 <b>-k1201x1201</b>
> srtm.sql<br>
psql -f srtm.sql TEST<br>
<br>
raster2pgsql.py -a -r N37E127.hgt -F N37E127 -t srtm3 -s 4327 <b>-k50x50</b>
> srtm.sql<br>
psql -f srtm.sql TEST<br>
<br>
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. <br>
<br>
Number of Lat/Lon Pairs Time in secs for
1201x1201 Time in secs for 50x50<br>
<br>
1000 17 sec
20 sec<br>
5000 85 sec
104 sec<br>
10000 167 sec
205 sec<br>
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