• cratedb geo 查询


    cratedb支持的geo 查询还相对比较全,开发基本的功能已经够用了

    安装cratedb

    使用docker

    docker run -d -p 4200:4200 crate

    创建数据库

    • 创建表
    CREATE TABLE country (
      name string,
      country_code string primary key,
      shape geo_shape INDEX USING "geohash" WITH (precision='100m'),
      capital string,
      capital_location geo_point
     ) WITH (number_of_replicas=0);
    • 添加数据
    INSERT INTO country (mame, country_code, shape, capital, capital_location)
     VALUES (
      'Austria',
      'at',
      {type='Polygon', coordinates=[
            [[16.979667, 48.123497], [16.903754, 47.714866],
            [16.340584, 47.712902], [16.534268, 47.496171],
            [16.202298, 46.852386], [16.011664, 46.683611],
            [15.137092, 46.658703], [14.632472, 46.431817],
            [13.806475, 46.509306], [12.376485, 46.767559],
            [12.153088, 47.115393], [11.164828, 46.941579],
            [11.048556, 46.751359], [10.442701, 46.893546],
            [9.932448, 46.920728], [9.47997, 47.10281],
            [9.632932, 47.347601], [9.594226, 47.525058],
            [9.896068, 47.580197], [10.402084, 47.302488],
            [10.544504, 47.566399], [11.426414, 47.523766],
            [12.141357, 47.703083], [12.62076, 47.672388],
            [12.932627, 47.467646], [13.025851, 47.637584],
            [12.884103, 48.289146], [13.243357, 48.416115],
            [13.595946, 48.877172], [14.338898, 48.555305],
            [14.901447, 48.964402], [15.253416, 49.039074],
            [16.029647, 48.733899], [16.499283, 48.785808],
            [16.960288, 48.596982], [16.879983, 48.470013],
            [16.979667, 48.123497]]
      ]},
      'Vienna',
      [16.372778, 48.209206]
     );

    数据查询

    具体语法可以参考参考资料对应的连接

    • 支持match
    SELECT name from country
     WHERE match("shape",
       'LINESTRING (13.3813 52.5229, 11.1840 51.5497, 8.6132 50.0782, 8.3715 47.9457, 8.5034 47.3685)'
     );
    • intersects distance within
    SELECT within(capital_location, shape) AS capital_in_country
     FROM country;
    
    SELECT distance(capital_location, 'POINT(0.0 90.0)') as from_northpole
     FROM country ORDER BY country_code;
    
    SELECT intersects(
       {type='LineString', coordinates=[[13.3813, 52.5229],
                                        [11.1840, 51.5497],
                                        [8.6132, 50.0782],
                                        [8.3715, 47.9457],
                                        [8.5034, 47.3685]]},
       shape) as berlin_zurich_intersects
     FROM country ORDER BY country_code;

    参考资料

    https://crate.io/docs/crate/reference/en/latest/general/dql/geo.html

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  • 原文地址:https://www.cnblogs.com/rongfengliang/p/9429900.html
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