根据经纬度在SQL语句中计算距离并排序

SELECT *,
ROUND(
6378.138 * 2 * ASIN(
SQRT(
POW(
SIN(
(
$lat * PI() / 180 - xx * PI() / 180 ) / 2 ), 2 ) + COS($lat * PI() / 180) * COS(xx * PI() / 180) * POW(
SIN(
(
$long * PI() / 180 - yy * PI() / 180
) / 2
),
2
)
)
) * 1000
) AS distance
FROM
tp_circle a LEFT JOIN tp_circle_identity b ON a.id = b.circle_id WHERE a.state=1
其中distance是距离