The tests were run on a PC running Slackware Linux with a kernel 2.6.9. The CPU was a P4 2.80GHz, the RAM was 512 Mb (which was too small).
Database parameters were set to their default values. No optimization was attempted.
Data are considered to be spread on a rectangular plane. The spherical geometry is not taken into account.
Postgresql, since a long time, has implemented geospatial features.
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