25个用于空间分析的PostGIS函数

SELECT ST_Area(geom) AS area
FROM datos.poligonos;

SELECT ST_Perimeter(geom) AS perímetro
FROM datos.poligonos;

SELECT ST_Length(geom) AS longitud
FROM datos.lineas;

SELECT ST_MakePoint(10 15);
SELECT ST_MakePoint(-3.7018, 40.3185);

SELECT  ST_MakeLine(geom) AS linea
FROM datos.puntos;

SELECT ST_MakeLine(id_puntos.geom) AS linea
FROM (
    SELECT puntos.id, geom
    FROM datos.puntos
    ORDER BY puntos.id
) AS id_puntos ;

SELECT ST_MakeLine(
    ARRAY[
        ST_MakePoint(5,2),
        ST_MakePoint(4,5),
        ST_MakePoint(8,10)
    ]
);

SELECT ST_MakePolygon(
    ST_GeomFromText(
        'LINESTRING(10 10, 15 10, 20 15, 10 15, 10 10)'
    )
);

SELECT ST_GeomFromText('POINT(20 20)')
SELECT ST_GeomFromText('LINESTRING(-5 10, 10 10, 10 15, 20 40, -10 20)')
SELECT ST_GeomFromText('POLYGON((10 10, 15 10, 10 15, 5 5, 10 10))')

SELECT AddGeometryColumn('datos', 'nuevospuntos', 'geom', 25830, 'POINT', 2)
SELECT DropGeometryColumn('datos', 'nuevospuntos', 'geom')

SELECT ST_Buffer(geom, 750)
FROM datos.lineas;

SELECT ST_SymDifference(
    parques.geom,
    ST_Buffer(papeleras.geom, 500))
FROM
datos.poligonos as parques,
datos.puntos as papeleras;

SELECT ST_Intersection(
    parques.geom,
    ST_Buffer(papeleras.geom, 500))
FROM
datos.poligonos as parques,
datos.puntos as papeleras;

SELECT ST_Union(lineas.geom, poligonos.geom)
FROM datos.lineas, datos.poligonos;

SELECT ST_Centroid(poligonos.geom)
FROM datos.poligonos;

SELECT ST_Envelope(lineas.geom)
FROM datos.lineas;

SELECT ST_Contains(poligonos.geom, lineas.geom)
FROM datos.lineas, datos.poligonos;

SELECT ST_Intersects(poligonos.geom, lineas.geom)
FROM datos.lineas, datos.poligonos;

SELECT ST_Overlaps(poligonos_a.geom, poligonos_b.geom)
FROM datos.poligonos_a, datos.poligonos_b;

SELECT ST_Touches(poligonos.geom, lineas.geom)
FROM datos.lineas, datos.poligonos;

SELECT ST_Covers(poligonos.geom, lineas.geom)
FROM datos.lineas, datos.poligonos;

SELECT ST_Translate(geom, -0.05, 0.25)
FROM datos.poligonos;

SELECT ST_Transform(geom, 4326)
FROM datos.poligonos;

SELECT ST_SRID(geom)
FROM datos.poligonos;

SELECT ST_SetSRID(ST_Point(-3.7018, 40.3185), 4326);

SELECT ST_GeometryType(geom) as tipo
FROM datos.poligonos;

SELECT ST_IsValid(geom) as validez
FROM datos.poligonos;

SELECT ST_IsValid(geom) as validez,
(select count(ST_IsValid(geom)) as numero)
FROM datos.poligonos
GROUP BY validez