SQL 查询示例：基于 EMPLOYEES 和 DEPARTMENTS 表的员工信息检索

(1) 雇用日期在今年的、工资在[1000,2000]之间的、或者员工姓名以'Obama'打头的所有员工的查询：

SELECT * FROM EMPLOYEES
WHERE HiredDate >= TO_DATE('2022-01-01', 'YYYY-MM-DD')
   OR (Salary >= 1000 AND Salary <= 2000)
   OR LAST_NAME LIKE 'Obama%';

(2) 部门平均工资大于1800元的部门的所有员工的查询：

SELECT E.* FROM EMPLOYEES E
INNER JOIN DEPARTMENTS D ON E.Departmentid = D.Departmentid
WHERE D.Departmentid IN (
   SELECT Departmentid
   FROM EMPLOYEES
   GROUP BY Departmentid
   HAVING AVG(Salary) > 1800
);

(3) 个人工资高于所在部门平均工资的员工的查询，包括高出部门平均工资的百分比：

SELECT E.*, (E.Salary - D.AvgSalary) / D.AvgSalary * 100 AS ExceedPercentage
FROM EMPLOYEES E
INNER JOIN (
   SELECT Departmentid, AVG(Salary) AS AvgSalary
   FROM EMPLOYEES
   GROUP BY Departmentid
) D ON E.Departmentid = D.Departmentid
WHERE E.Salary > D.AvgSalary;

注意：以上查询语句仅提供了基于给定表结构的查询示例，并假设表已经存在且包含合适的数据。实际使用时，可能需要根据具体情况进行适当的调整和修改。