ST_DIMENSION

返回几何对象的维度。GEOMETRY 或 GEOGRAPHY 对象的维度如下：

语法

ST_DIMENSION(<geometry_or_geography>)

参数

返回类型

UInt8。

示例

GEOMETRY 示例

SELECT
  ST_DIMENSION(
    ST_GEOMETRYFROMWKT(
      'POINT(-122.306100 37.554162)'
    )
  ) AS pipeline_dimension;

┌────────────────────┐
│ pipeline_dimension │
├────────────────────┤
│                  0 │
└────────────────────┘

SELECT
  ST_DIMENSION(
    ST_GEOMETRYFROMWKT(
      'LINESTRING(-124.20 42.00, -120.01 41.99)'
    )
  ) AS pipeline_dimension;

┌────────────────────┐
│ pipeline_dimension │
├────────────────────┤
│                  1 │
└────────────────────┘

SELECT
  ST_DIMENSION(
    ST_GEOMETRYFROMWKT(
      'POLYGON((-124.20 42.00, -120.01 41.99, -121.1 42.01, -124.20 42.00))'
    )
  ) AS pipeline_dimension;

┌────────────────────┐
│ pipeline_dimension │
├────────────────────┤
│                  2 │
└────────────────────┘

GEOGRAPHY 示例

SELECT
  ST_DIMENSION(
    ST_GEOGFROMWKT(
      'LINESTRING(-124.20 42.00, -120.01 41.99)'
    )
  ) AS pipeline_dimension;

╭────────────────────╮
│ pipeline_dimension │
├────────────────────┤
│                  1 │
╰────────────────────╯