数据库基本训练

#175组合两个表

SELECT a.FirstName, a.lastName, b.City, b.State 
From Person AS a LEFT JOIN Address AS b ON a.PersonId = b.PersonId;

#177第N高薪水

CREATE FUNCTION getNthHighestSalary(N INT) RETURNS INT
BEGIN
SET N = N-1;
  RETURN (
      # Write your MySQL query statement below.
      SELECT DISTINCT SALARY
      FROM EMPLOYEE
      ORDER BY SALARY DESC
      LIMIT 1
      // 跳过前n-1个
      OFFSET N
  );
END