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fix link for current PostGis HP
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Erwin Brandstetter
Erwin Brandstetter
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The right answer is choice #5: use PostGISPostGIS. An example from OpenGeo:

"Note the magic <-> operator in the ORDER BY clause. This is where the magic occurs. The <-> is a “distance” operator, but it only makes use of the index when it appears in the ORDER BY clause. Between putting the operator in the ORDER BY and using a LIMIT to truncate the result set, we can very very quickly (less than 10ms on a 2M record table, in this case) get the 10 nearest points to our test point."

(emphasis added)

The right answer is choice #5: use PostGIS. An example from OpenGeo:

"Note the magic <-> operator in the ORDER BY clause. This is where the magic occurs. The <-> is a “distance” operator, but it only makes use of the index when it appears in the ORDER BY clause. Between putting the operator in the ORDER BY and using a LIMIT to truncate the result set, we can very very quickly (less than 10ms on a 2M record table, in this case) get the 10 nearest points to our test point."

(emphasis added)

The right answer is choice #5: use PostGIS. An example from OpenGeo:

"Note the magic <-> operator in the ORDER BY clause. This is where the magic occurs. The <-> is a “distance” operator, but it only makes use of the index when it appears in the ORDER BY clause. Between putting the operator in the ORDER BY and using a LIMIT to truncate the result set, we can very very quickly (less than 10ms on a 2M record table, in this case) get the 10 nearest points to our test point."

(emphasis added)

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Daniel Lyons
Daniel Lyons
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The right answer is choice #5: use PostGIS. An example from OpenGeo:

"Note the magic <-> operator in the ORDER BY clause. This is where the magic occurs. The <-> is a “distance” operator, but it only makes use of the index when it appears in the ORDER BY clause. Between putting the operator in the ORDER BY and using a LIMIT to truncate the result set, we can very very quickly (less than 10ms on a 2M record table, in this case) get the 10 nearest points to our test point."

(emphasis added)