circle的半径 1000和米应该怎样换算呢

[pyma]

• hi 请问一下下列sql语句中circle的半径 1000和米应该怎样换算呢

select * from cb where c1=0 and c2=100 and c3 <@ circle '((23,3175),1000)' order by c3 <-> point(23,3175) limit 1000;