ST_Area_Square_Meters,ST_Area_Square_Km

Syntax

  1. DOUBLE ST_Area_Square_Meters(GEOMETRY geo)
  2. DOUBLE ST_Area_Square_Km(GEOMETRY geo)

description

计算地球球面上区域的面积，目前参数geo支持St_Point,St_LineString,St_Circle和St_Polygon。

如果输入的是St_Point,St_LineString，则返回零。

其中，ST_Area_Square_Meters(GEOMETRY geo)返回的单位是平方米，ST_Area_Square_Km(GEOMETRY geo)返回的单位是平方千米。

example

  1. mysql> SELECT ST_Area_Square_Meters(ST_Circle(0, 0, 1));
  2. +-------------------------------------------------+
  3. | st_area_square_meters(st_circle(0.0, 0.0, 1.0)) |
  4. +-------------------------------------------------+
  5. |                              3.1415926535897869 |
  6. +-------------------------------------------------+
  7. 1 row in set (0.04 sec)
  9. mysql> SELECT ST_Area_Square_Km(ST_Polygon("POLYGON ((0 0, 1 0, 1 1, 0 1, 0 0))"));
  10. +----------------------------------------------------------------------+
  11. | st_area_square_km(st_polygon('POLYGON ((0 0, 1 0, 1 1, 0 1, 0 0))')) |
  12. +----------------------------------------------------------------------+
  13. |                                                   12364.036567076409 |
  14. +----------------------------------------------------------------------+
  15. 1 row in set (0.01 sec)
  17. mysql> SELECT ST_Area_Square_Meters(ST_Point(0, 1));
  18. +-------------------------------------------+
  19. | st_area_square_meters(st_point(0.0, 1.0)) |
  20. +-------------------------------------------+
  21. |                                         0 |
  22. +-------------------------------------------+
  23. 1 row in set (0.05 sec)
  25. mysql> SELECT ST_Area_Square_Meters(ST_LineFromText("LINESTRING (1 1, 2 2)"));
  26. +-----------------------------------------------------------------+
  27. | st_area_square_meters(st_linefromtext('LINESTRING (1 1, 2 2)')) |
  28. +-----------------------------------------------------------------+
  29. |                                                               0 |
  30. +-----------------------------------------------------------------+
  31. 1 row in set (0.03 sec)

keywords

ST_Area_Square_Meters,ST_Area_Square_Km,ST_Area,ST,Area