st_npoints function
Applies to:  Databricks SQL 
 Databricks Runtime 17.1 and above
Preview
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注記
This feature is not available on Databricks SQL Classic warehouses. To learn more about Databricks SQL warehouses, see SQL warehouse types.
Returns the number of non-empty points in the input GEOGRAPHY or GEOMETRY value.
Syntax
st_npoints ( geoExpr )
Arguments
geoExpr: AGEOGRAPHYorGEOMETRYvalue.
Returns
A value of type INT, representing the number of non-empty points in the input GEOGRAPHY or GEOMETRY value.
The function returns NULL if the input is NULL.
Examples
SQL
-- Returns the number of points in a non-empty multipoint geometry.
> SELECT st_npoints(st_geomfromtext('MULTIPOINT(10 34,44 57,EMPTY)'));
  2
-- Returns the number of points in an empty multipoint geometry.
> SELECT st_npoints(st_geomfromtext('MULTIPOINT(EMPTY,EMPTY)'));
  0
-- Returns the number of points in a non-empty polygon geometry.
> SELECT st_npoints(st_geomfromtext('POLYGON((0 0,1 0,1 1,0 1,0 0))'));
  5