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是否有一种方便的方法,以Sqlalchemy或Geoalchemy制作空间指数?
原标题:Is there a convenient way to create spatial index with Sqlalchemy or Geoalchemy?

昨天有人告诉我,如果我想使用Sqlalchemy,Geoalchemy是支持空间延伸的良好选择。 这确实是好的。 非常感谢他。

但是,我没有找到一种方便的方式来制定具有地质构造的空间指数。 我是否应该直接管理这一结构?

CREATE SPATIAL INDEX sp_index ON my_class (
geom_col
);

是否有一种方便的方法,不直接撰写文件。

感谢!

问题回答

在建立一个有<代码>的表格时()。 GeoAlchemy将自动为地貌相列设定一个指数。

此外,Alchemy Indexs 例有create方法。 See the “Indexes” section in http://docs.sqlalchemy.org/en/rel_0_7/core/schema.html#metadata-constraints 。 我不敢肯定,你是否能够在我的SQL中建立一个空间指数,但值得尝试。

With GeoAlchemy, there are 2 steps you should take to create Spatial Index on the geometry column

  • add attr spatial_index to the geometry column
  • Call the GeometryDDL extension

例:

# note that spatial_index will set the column to not null 
class Building(Base):
    geom = GeometryColumn(Point(2, spatial_index=True))

GeometryDDL(Building.__table__)




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