[postgis-users] Histogram2d formation

[David Blasby]

Here's an example of the histogram creation for BC roads data.

One has a grid size of 20*20, the other 40*40 - see the attached .gif
files.

This histogram formation only takes a few seconds!

Next, I'm going to try to find a way of estimating the result set size
based on a query window.  If anyone has any ideas how to go about doing
this (esp for very small query windows), I'd like to hear from you.

dave
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