2000-06-16 03:05:22 +08:00
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--------------- geo_distance
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DROP FUNCTION geo_distance (point, point);
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CREATE FUNCTION geo_distance (point, point) RETURNS float8
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2001-08-17 06:24:43 +08:00
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AS 'MODULE_PATHNAME' LANGUAGE 'c'
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WITH (isstrict);
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2000-06-16 03:05:22 +08:00
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SELECT geo_distance ('(1,2)'::point, '(3,4)'::point);
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--------------- geo_distance as operator <@>
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DROP OPERATOR <@> (point, point);
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CREATE OPERATOR <@> (
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leftarg = point,
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rightarg = point,
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procedure = geo_distance,
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commutator = <@>
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);
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-- ( 87.6, 41.8) is in Chicago
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-- (106.7, 35.1) is in Albuquerque
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-- The cities are about 1100 miles apart
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SELECT '(87.6,41.8)'::point <@> '(106.7,35.1)'::point;
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