LeetCode（数据库）- 2016年的投资

题目链接：​​点击打开链接​​

题目大意：略。

解题思路：略。

AC 代码

-- 解决方案(1)
SELECT
    SUM(insurance.TIV_2016) AS TIV_2016
FROM
    insurance
WHERE
    insurance.TIV_2015 IN
    (
      SELECT
        TIV_2015
      FROM
        insurance
      GROUP BY TIV_2015
      HAVING COUNT(*) > 1
    )
    AND CONCAT(LAT, LON) IN
    (
      SELECT
        CONCAT(LAT, LON)
      FROM
        insurance
      GROUP BY LAT , LON
      HAVING COUNT(*) = 1
    )
;

-- 解决方案(2)
SELECT ROUND(SUM(TIV_2016), 2) TIV_2016
FROM insurance ins
WHERE (SELECT COUNT(TIV_2015) > 0 FROM insurance WHERE PID <> ins.PID AND TIV_2015 = ins.TIV_2015)
AND (SELECT COUNT(1) = 1 FROM insurance WHERE LAT = ins.LAT AND LON = ins.LON)