Mixes of POINTS and MULTIPOINTS, LINESTRING and MULTILINESTRING, POLYGON and MULTIPOLYGON are returned as MULTIPOINTS, MULTILINESTRING and MULTIPOLYGONS respectively
st_cast_sfc_default(x)
list of geometries or simple features
Geometries that are already MULTI* are left unchanged. Features that can't be cast to a single MULTI* geometry are return as a GEOMETRYCOLLECTION