SELECT a.address,
a.cont AS countAddress,
b.sum AS sumAddress,
CONCAT( ROUND( a.cont / b.sum * 100, 2 ), ‘‘, ‘%‘ ) AS percent
FROM
( SELECT address, COUNT( address ) AS cont FROM person_base_info GROUP BY address ) a,
(SELECT COUNT(*) AS sum FROM person_base_info ) b
原文：https://www.cnblogs.com/magichu/p/14770788.html