Ganos Geometry是对象关系型数据库PostgreSQL的一个空间几何扩展,Ganos Geometry遵循OpenGIS规范,使PostgreSQL增加了存储和管理2D(X,Y)、3D(X,Y,Z)、4D(X,Y,Z,M)空间几何数据的能力,并提供了空间几何对象、索引、函数和操作符等丰富功能。

概述

几何模型完全兼容PostGIS接口,支持已有应用的平滑迁移。

快速入门

  • 创建扩展

    --创建几何扩展
    Create extension ganos_geometry cascade;
    
    --创建几何拓扑扩展
    Create extension ganos_geometry_topology;
    
    --创建sfcgal插件扩展
    Create extension ganos_geometry_sfcgal;
  • 创建几何表

    --方式一:直接创建带geometry字段的表
    CREATE TABLE ROADS ( ID int4, ROAD_NAME varchar(25), geom geometry(LINESTRING,4326) );
    
    --方式二:先创建普通表,再附加几何字段
    CREATE TABLE ROADS ( ID int4, ROAD_NAME varchar(25) );
    SELECT AddGeometryColumn( 'roads', 'geom', 4326, 'LINESTRING', 2);
  • 添加几何约束

    ALTER TABLE ROADS ADD CONSTRAINT geometry_valid_check CHECK (ST_IsValid(geom));
  • 导入几何数据

    INSERT INTO roads (id, geom, road_name)
      VALUES (1,ST_GeomFromText('LINESTRING(191232 243118,191108 243242)',-1),'北五环');
    INSERT INTO roads (id, geom, road_name)
      VALUES (2,ST_GeomFromText('LINESTRING(189141 244158,189265 244817)',-1),'东五环');
    INSERT INTO roads (id, geom, road_name)
      VALUES (3,ST_GeomFromText('LINESTRING(192783 228138,192612 229814)',-1),'南五环');
    INSERT INTO roads (id, geom, road_name)
      VALUES (4,ST_GeomFromText('LINESTRING(189412 252431,189631 259122)',-1),'西五环');
    INSERT INTO roads (id, geom, road_name)
      VALUES (5,ST_GeomFromText('LINESTRING(190131 224148,190871 228134)',-1),'东长安街');
    INSERT INTO roads (id, geom, road_name)
      VALUES (6,ST_GeomFromText('LINESTRING(198231 263418,198213 268322)',-1),'西长安街');
  • 查询几何对象信息

    SELECT id, ST_AsText(geom) AS geom, road_name FROM roads;
    
    --------------------------------
         id | geom                                    | road_name
    --------+-----------------------------------------+-----------
          1 | LINESTRING(191232 243118,191108 243242) | 北五环
          2 | LINESTRING(189141 244158,189265 244817) | 东五环
          3 | LINESTRING(192783 228138,192612 229814) | 南五环
          4 | LINESTRING(189412 252431,189631 259122) | 西五环
          5 | LINESTRING(190131 224148,190871 228134) | 东长安街
          6 | LINESTRING(198231 263418,198213 268322) | 西长安街
    (6 rows)
  • 创建索引

    --GiST索引
    CREATE INDEX [indexname] ON [tablename] USING GIST ( [geometryfield] ); 
    CREATE INDEX [indexname] ON [tablename] USING GIST ([geometryfield] gist_geometry_ops_nd);
    VACUUM ANALYZE [table_name] [(column_name)];
    
    --举例
    Create INDEX sp_geom_index ON ROADS USING GIST(geom);
    VACUUM ANALYZE ROADS (geom);
    
    --创建BRIN索引
    CREATE INDEX [indexname] ON [tablename] USING BRIN ( [geometryfield] ); 
    CREATE INDEX [indexname] ON [tablename] USING BRIN ([geometryfield] brin_geometry_inclusion_ops_3d);
    CREATE INDEX [indexname] ON [tablename] USING BRIN ([geometryfield] brin_geometry_inclusion_ops_4d);
    --创建指定大小的brin索引
    CREATE INDEX [indexname] ON [tablename] USING BRIN ( [geometryfield] ) WITH (pages_per_range = [number]);
  • 几何对象存取

    ---判断空间几何对象是否是简单要素类型
     SELECT ST_IsSimple(ST_GeomFromText('POLYGON((1 2, 3 4, 5 6, 1 2))'));
     st_issimple
    -------------
     t
    (1 row)
    
     SELECT ST_IsSimple(ST_GeomFromText('LINESTRING(1 1,2 2,2 3.5,1 3,1 2,2 1)'));
     st_issimple
    -------------
     f
    (1 row)
    
    
    --查询地形中拥有环岛且面积最大的城市
    SELECT gid, name, ST_Area(the_geom) AS area
    FROM bc_municipality
    WHERE ST_NRings(the_geom) > 1
    ORDER BY area DESC LIMIT 1;
    
    gid  | name         | area
    -----+--------------+------------------
    12   | 安宁市        | 257374619.430216
    (1 row)
  • 空间测量、空间分析和空间关系判断

    --创建表bc_roads 
    Create table bc_roads (gid serial, name varchar, the_geom geometry);
    
    --创建表bc_municipality
    Create table bc_municipality(gid serial, code integer, name varchar, the_geom geometry);
    
    --长度计算
    SELECT sum(ST_Length(the_geom))/1000 AS km_roads FROM bc_roads;
    
    km_roads
    ------------------
    70842.1243039643
    (1 row)
    
    --面积计算
    SELECT ST_Area(the_geom)/10000 AS hectares FROM bc_municipality WHERE name = 'PRINCE GEORGE';
    
    hectares
    ------------------
    32657.9103824927
    (1 row)
    --使用ST_Contains函数
    SELECT  m.name, sum(ST_Length(r.the_geom))/1000 as roads_km
    FROM
      bc_roads AS r, bc_municipality AS m
    WHERE
      ST_Contains(m.the_geom,r.the_geom)
    GROUP BY m.name
    ORDER BY roads_km;
    
    name                        | roads_km
    ----------------------------+------------------
    SURREY                      | 1539.47553551242
    VANCOUVER                   | 1450.33093486576
    LANGLEY DISTRICT            | 833.793392535662
    BURNABY                     | 773.769091404338
    PRINCE GEORGE               | 694.37554369147
    
    
    --使用ST_Covers函数
    SELECT ST_Covers(smallc,smallc) As smallinsmall,
        ST_Covers(smallc, bigc) As smallcoversbig,
        ST_Covers(bigc, ST_ExteriorRing(bigc)) As bigcoversexterior,
        ST_Contains(bigc, ST_ExteriorRing(bigc)) As bigcontainsexterior
    FROM (SELECT ST_Buffer(ST_GeomFromText('POINT(1 2)'), 10) As smallc,
        ST_Buffer(ST_GeomFromText('POINT(1 2)'), 20) As bigc) As foo;
        --Result
     smallinsmall | smallcoversbig | bigcoversexterior | bigcontainsexterior
    --------------+----------------+-------------------+---------------------
     t            | f              | t                 | f
    (1 row)    
    
    --使用ST_Disjoint函数
    SELECT ST_Disjoint('POINT(0 0)'::geometry, 'LINESTRING ( 2 0, 0 2 )'::geometry);
     st_disjoint
    ---------------
     t
    (1 row)
    SELECT ST_Disjoint('POINT(0 0)'::geometry, 'LINESTRING ( 0 0, 0 2 )'::geometry);
     st_disjoint
    ---------------
     f
    (1 row)
    
    --使用ST_Overlaps函数
    SELECT ST_Overlaps(a,b) As a_overlap_b,
        ST_Crosses(a,b) As a_crosses_b,
            ST_Intersects(a, b) As a_intersects_b, ST_Contains(b,a) As b_contains_a
    FROM (SELECT ST_GeomFromText('POINT(1 0.5)') As a, ST_GeomFromText('LINESTRING(1 0, 1 1, 3 5)')  As b)
        As foo
    
    a_overlap_b | a_crosses_b | a_intersects_b | b_contains_a
    ------------+-------------+----------------+--------------
    f           | f           | t              | t
    
    --使用ST_Relate函数
    SELECT ST_Relate(ST_GeometryFromText('POINT(1 2)'), ST_Buffer(ST_GeometryFromText('POINT(1 2)'),2), '0FFFFF212');
    st_relate
    -----------
    t
    
    --使用ST_Touches函数
    SELECT ST_Touches('LINESTRING(0 0, 1 1, 0 2)'::geometry, 'POINT(1 1)'::geometry);
     st_touches
    ------------
     f
    (1 row)
    
    SELECT ST_Touches('LINESTRING(0 0, 1 1, 0 2)'::geometry, 'POINT(0 2)'::geometry);
     st_touches
    ------------
     t
    (1 row)
    
    --使用ST_Within函数
    SELECT ST_Within(smallc,smallc) As smallinsmall,
        ST_Within(smallc, bigc) As smallinbig,
        ST_Within(bigc,smallc) As biginsmall,
        ST_Within(ST_Union(smallc, bigc), bigc) as unioninbig,
        ST_Within(bigc, ST_Union(smallc, bigc)) as biginunion,
        ST_Equals(bigc, ST_Union(smallc, bigc)) as bigisunion
    FROM
    (
    SELECT ST_Buffer(ST_GeomFromText('POINT(50 50)'), 20) As smallc,
        ST_Buffer(ST_GeomFromText('POINT(50 50)'), 40) As bigc) As foo;
    --Result
     smallinsmall | smallinbig | biginsmall | unioninbig | biginunion | bigisunion
    --------------+------------+------------+------------+------------+------------
     t            | t          | f          | t          | t          | t
    (1 row)
  • 删除扩展

    Drop extension ganos_geometry cascade;

SQL参考

详细SQL手册请参考 PostGIS官方手册