mysql答案语句如下：
use test1;
CREATE TABLE test1 (city varchar(10), gender char(1));
INSERT INTO test1 (city, gender)
VALUES ('Delhi', 'M')
,('Delhi', 'F')
,('Delhi', 'M')
,('Delhi', 'M')
,('Pune', 'F')
,('Pune', 'M')
,('Pune', 'F')
,('Pune', 'F')
,('Banglore', 'F')
,('Banglore', 'F')
;
SELECT city,COUNT(*)AS "人数合计",
SUM(CASE WHEN gender='M' THEN 1 ELSE 0 END)AS "女士人数",
SUM(CASE WHEN gender='F' THEN 1 ELSE 0 END) AS "男士人数"
FROM test1 GROUP BY city ;
