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029fac2264
It was never terribly consistent to use OR REPLACE (because of the lack of comparable functionality for data types, operators, etc), and experimentation shows that it's now positively pernicious in the extension world. We really want a failure to occur if there are any conflicts, else it's unclear what the extension-ownership state of the conflicted object ought to be. Most of the time, CREATE EXTENSION will fail anyway because of conflicts on other object types, but an extension defining only functions can succeed, with bad results.
89 lines
2.9 KiB
SQL
89 lines
2.9 KiB
SQL
/* contrib/earthdistance/earthdistance--1.0.sql */
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-- earth() returns the radius of the earth in meters. This is the only
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-- place you need to change things for the cube base distance functions
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-- in order to use different units (or a better value for the Earth's radius).
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CREATE FUNCTION earth() RETURNS float8
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LANGUAGE SQL IMMUTABLE
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AS 'SELECT ''6378168''::float8';
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-- Astromers may want to change the earth function so that distances will be
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-- returned in degrees. To do this comment out the above definition and
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-- uncomment the one below. Note that doing this will break the regression
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-- tests.
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--
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-- CREATE FUNCTION earth() RETURNS float8
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-- LANGUAGE SQL IMMUTABLE
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-- AS 'SELECT 180/pi()';
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-- Define domain for locations on the surface of the earth using a cube
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-- datatype with constraints. cube provides 3D indexing.
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-- The cube is restricted to be a point, no more than 3 dimensions
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-- (for less than 3 dimensions 0 is assumed for the missing coordinates)
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-- and that the point must be very near the surface of the sphere
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-- centered about the origin with the radius of the earth.
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CREATE DOMAIN earth AS cube
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CONSTRAINT not_point check(cube_is_point(value))
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CONSTRAINT not_3d check(cube_dim(value) <= 3)
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CONSTRAINT on_surface check(abs(cube_distance(value, '(0)'::cube) /
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earth() - 1) < '10e-7'::float8);
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CREATE FUNCTION sec_to_gc(float8)
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RETURNS float8
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LANGUAGE SQL
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IMMUTABLE STRICT
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AS 'SELECT CASE WHEN $1 < 0 THEN 0::float8 WHEN $1/(2*earth()) > 1 THEN pi()*earth() ELSE 2*earth()*asin($1/(2*earth())) END';
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CREATE FUNCTION gc_to_sec(float8)
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RETURNS float8
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LANGUAGE SQL
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IMMUTABLE STRICT
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AS 'SELECT CASE WHEN $1 < 0 THEN 0::float8 WHEN $1/earth() > pi() THEN 2*earth() ELSE 2*earth()*sin($1/(2*earth())) END';
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CREATE FUNCTION ll_to_earth(float8, float8)
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RETURNS earth
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LANGUAGE SQL
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IMMUTABLE STRICT
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AS 'SELECT cube(cube(cube(earth()*cos(radians($1))*cos(radians($2))),earth()*cos(radians($1))*sin(radians($2))),earth()*sin(radians($1)))::earth';
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CREATE FUNCTION latitude(earth)
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RETURNS float8
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LANGUAGE SQL
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IMMUTABLE STRICT
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AS 'SELECT CASE WHEN cube_ll_coord($1, 3)/earth() < -1 THEN -90::float8 WHEN cube_ll_coord($1, 3)/earth() > 1 THEN 90::float8 ELSE degrees(asin(cube_ll_coord($1, 3)/earth())) END';
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CREATE FUNCTION longitude(earth)
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RETURNS float8
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LANGUAGE SQL
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IMMUTABLE STRICT
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AS 'SELECT degrees(atan2(cube_ll_coord($1, 2), cube_ll_coord($1, 1)))';
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CREATE FUNCTION earth_distance(earth, earth)
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RETURNS float8
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LANGUAGE SQL
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IMMUTABLE STRICT
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AS 'SELECT sec_to_gc(cube_distance($1, $2))';
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CREATE FUNCTION earth_box(earth, float8)
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RETURNS cube
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LANGUAGE SQL
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IMMUTABLE STRICT
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AS 'SELECT cube_enlarge($1, gc_to_sec($2), 3)';
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--------------- geo_distance
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CREATE FUNCTION geo_distance (point, point)
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RETURNS float8
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LANGUAGE C IMMUTABLE STRICT AS 'MODULE_PATHNAME';
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--------------- geo_distance as operator <@>
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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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