# ST_Area

## ST_Area_Square_Meters,ST_Area_Square_Kmβ

### Syntaxβ

``DOUBLE ST_Area_Square_Meters(GEOMETRY geo)DOUBLE ST_Area_Square_Km(GEOMETRY geo)``

### descriptionβ

Calculate the area of the area on the earth's sphere. Currently, the parameter geo supports St_Point, St_LineString, St_Circle and St_Polygon.

Returns zero if the input is St_Point, St_LineString.

Among them, the unit returned by ST_Area_Square_Meters (GEOMETRY geo) is square meters, and the unit returned by ST_Area_Square_Km (GEOMETRY geo) is square kilometers.

### exampleβ

``mysql> SELECT ST_Area_Square_Meters(ST_Circle(0, 0, 1));+-------------------------------------------------+| st_area_square_meters(st_circle(0.0, 0.0, 1.0)) |+-------------------------------------------------+|                              3.1415926535897869 |+-------------------------------------------------+1 row in set (0.04 sec)mysql> SELECT ST_Area_Square_Km(ST_Polygon("POLYGON ((0 0, 1 0, 1 1, 0 1, 0 0))"));+----------------------------------------------------------------------+| st_area_square_km(st_polygon('POLYGON ((0 0, 1 0, 1 1, 0 1, 0 0))')) |+----------------------------------------------------------------------+|                                                   12364.036567076409 |+----------------------------------------------------------------------+1 row in set (0.01 sec)mysql> SELECT ST_Area_Square_Meters(ST_Point(0, 1));+-------------------------------------------+| st_area_square_meters(st_point(0.0, 1.0)) |+-------------------------------------------+|                                         0 |+-------------------------------------------+1 row in set (0.05 sec)mysql> SELECT ST_Area_Square_Meters(ST_LineFromText("LINESTRING (1 1, 2 2)"));+-----------------------------------------------------------------+| st_area_square_meters(st_linefromtext('LINESTRING (1 1, 2 2)')) |+-----------------------------------------------------------------+|                                                               0 |+-----------------------------------------------------------------+1 row in set (0.03 sec)``

### keywordsβ

ST_Area_Square_Meters,ST_Area_Square_Km,ST_Area,ST,Area