GIS and Media fusion
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geoinf14:postgis1
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| Both sides previous revision Previous revision Next revision | Previous revision | ||
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geoinf14:postgis1 [2014/12/09 09:39] oertz [Spatial Query Language :: Part1] |
geoinf14:postgis1 [2018/05/16 10:05] (current) |
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| ===== Premiers pas ===== | ===== Premiers pas ===== | ||
| (-> cf. documentation [[http://postgis.refractions.net/documentation/manual-1.5/reference.html|PostGIS Reference]]) | (-> cf. documentation [[http://postgis.refractions.net/documentation/manual-1.5/reference.html|PostGIS Reference]]) | ||
| - | - Quelles sont les aires des objets ? -> ST_Area2d<code>...</code> | + | - Quelles sont les aires des objets ? -> ST_Area2d<code>cf. 2</code> |
| - | - Quel sont les types géométriques des objets ? -> Geometrytype<code>...</code> | + | - Quel sont les types géométriques des objets ? -> Geometrytype<code> |
| - | - Quel est l'objet géométrique le plus proche du pieton 2 ? -> ST_Distance<code>...</code> | + | SELECT *, ST_Area(the_geom) FROM test WHERE ST_Geometrytype(the_geom) = 'ST_Polygon' |
| - | - Qui est dans le bâtiment 2 ? -> ST_Within<code>...</code> | + | </code> |
| + | - Quel est l'objet géométrique le plus proche du pieton 2 ? -> ST_Distance<code> | ||
| + | SELECT genre, ST_Distance(the_geom, (SELECT the_geom FROM test WHERE id = 2)) as dist FROM test | ||
| + | WHERE id <> 2 ORDER BY dist LIMIT 1 | ||
| + | |||
| + | OU | ||
| + | |||
| + | SELECT t1.* FROM test t1, test t2 WHERE t2.genre LIKE 'pieton2' | ||
| + | AND ST_Distance(t1.the_geom,t2.the_geom) = ( | ||
| + | SELECT min(ST_Distance(t1.the_geom, t2.the_geom)) FROM test t1, test t2 | ||
| + | WHERE t1.genre LIKE 'pieton2' AND t2.genre <> 'pieton2' | ||
| + | ) | ||
| + | </code> | ||
| + | - Qui est dans le bâtiment 2 ? -> ST_Within<code> | ||
| + | SELECT * FROM test WHERE genre like 'pieton%' | ||
| + | AND ST_WithIn(test.the_geom, (SELECT the_geom FROM test WHERE genre LIKE 'batiment2')); | ||
| + | </code> | ||
| //(source: [[http://www.davidgis.fr|Jean David Techer]])// | //(source: [[http://www.davidgis.fr|Jean David Techer]])// | ||
geoinf14/postgis1.1418114345.txt.gz · Last modified: 2018/05/16 10:05 (external edit)
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