Postgresql ArcMap联合的PostGIS等价物

在PostGIS/PostgreSQL中，ArcMap中的操作等效于什么

假设您有两个分别具有两个特征的形状文件。（PostGIS等效：两个表，两行，多边形几何）

然后，结果将是1个具有7个特征的shapefile。（PostGIS等价物：具有7行几何图形的表）

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我看过ST_Intersect、ST_Union和ST_Collect，但找不到正确的组合。非常感谢你的帮助

以下是基于以下答案的工作查询：

从a）读到d）：

结果:

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非常感谢迈克尔·恩廷

-- input data
with polys1 AS (
  SELECT 1 df1, ST_GeogFromText('Polygon((0 0, 2 0, 2 2, 0 2, 0 0))') g
  UNION ALL
  SELECT 2, ST_GeogFromText('Polygon((2 2, 4 2, 4 4, 2 4, 2 2))')
),
polys2 AS (
  SELECT 1 df2, ST_GeogFromText('Polygon((1 1, 3 1, 3 3, 1 3, 1 1))') g
  UNION ALL
  SELECT 2, ST_GeogFromText('Polygon((3 3, 5 3, 5 5, 3 5, 3 3))')
),
-- left and right unions
union1 AS (
  SELECT ST_UNION_AGG(g) FROM polys1
),
union2 AS (
  SELECT ST_UNION_AGG(g) FROM polys2
),
-- various combinations of intersections
pairs AS (
  SELECT df1, df2, ST_INTERSECTION(a.g, b.g) g FROM polys1 a, polys2 b WHERE ST_INTERSECTS(a.g, b.g)
  UNION ALL
  SELECT df1, NULL, ST_DIFFERENCE(g, (SELECT * FROM union2)) g FROM polys1
  UNION ALL 
  SELECT NULL, df2, ST_DIFFERENCE(g, (SELECT * FROM union1)) g FROM polys2
)
SELECT * FROM pairs WHERE NOT ST_IsEmpty(g)

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请在gis.se上查看此答案：注意

ST_ExteriorRing

会掉任何洞

ST_Boundary

将保留内环，但也将在内环内创建多边形。

-- input data
with polys1 AS (
  SELECT 1 df1, ST_GeogFromText('Polygon((0 0, 2 0, 2 2, 0 2, 0 0))') g
  UNION ALL
  SELECT 2, ST_GeogFromText('Polygon((2 2, 4 2, 4 4, 2 4, 2 2))')
),
polys2 AS (
  SELECT 1 df2, ST_GeogFromText('Polygon((1 1, 3 1, 3 3, 1 3, 1 1))') g
  UNION ALL
  SELECT 2, ST_GeogFromText('Polygon((3 3, 5 3, 5 5, 3 5, 3 3))')
),
-- left and right unions
union1 AS (
  SELECT ST_UNION_AGG(g) FROM polys1
),
union2 AS (
  SELECT ST_UNION_AGG(g) FROM polys2
),
-- various combinations of intersections
pairs AS (
  SELECT df1, df2, ST_INTERSECTION(a.g, b.g) g FROM polys1 a, polys2 b WHERE ST_INTERSECTS(a.g, b.g)
  UNION ALL
  SELECT df1, NULL, ST_DIFFERENCE(g, (SELECT * FROM union2)) g FROM polys1
  UNION ALL 
  SELECT NULL, df2, ST_DIFFERENCE(g, (SELECT * FROM union1)) g FROM polys2
)
SELECT * FROM pairs WHERE NOT ST_IsEmpty(g)