ST_MakePointM — 从X、Y和M值创建点。
geometry
ST_MakePointM
(
float
x
, float
y
, float
m
)
;
创建具有未知SRID的点。
SELECT ST_AsEWKT( ST_MakePointM(-71.1043443253471, 42.3150676015829, 10) );
st_asewkt
-----------------------------------------------
POINTM(-71.1043443253471 42.3150676015829 10)
使用WGS 84大地坐标系中的测量创建点。
SELECT ST_AsEWKT( ST_SetSRID( ST_MakePointM(-71.104, 42.315, 10), 4326));
st_asewkt
---------------------------------------------------------
SRID=4326;POINTM(-71.104 42.315 10)
获取创建点的度量值。
SELECT ST_M( ST_MakePointM(-71.104, 42.315, 10) );
result
-------
10