创建一个包，要求该包中包含下面的功能：对于YGGL数据库中已存在的员工表，输入员工所在的部门编号，创建函数，计算该部门员工的平均收入；创建存储过程，查询该部门员工的最低收入，调用包时在屏幕上显示查询信息。

首先，在数据库中创建一个员工表，包含员工编号、姓名、部门编号、收入等字段。我们可以使用下面的SQL语句创建一个名为"employees"的员工表：

CREATE TABLE employees (
    emp_id INT PRIMARY KEY,
    emp_name VARCHAR(50),
    dept_id INT,
    salary INT
);

接下来，我们可以创建一个名为"employee_pkg"的包，该包包含两个函数和一个存储过程：

1. 一个名为"get_avg_salary"的函数，用于计算指定部门的平均收入。该函数接受一个部门编号作为参数，并返回该部门员工的平均收入。函数的实现如下：

CREATE OR REPLACE PACKAGE employee_pkg AS
    FUNCTION get_avg_salary(dept_id IN INT) RETURN INT;
    PROCEDURE get_min_salary(dept_id IN INT);
END employee_pkg;
/

CREATE OR REPLACE PACKAGE BODY employee_pkg AS
    FUNCTION get_avg_salary(dept_id IN INT) RETURN INT AS
        avg_salary INT;
    BEGIN
        SELECT AVG(salary) INTO avg_salary FROM employees WHERE dept_id = dept_id;
        RETURN avg_salary;
    END get_avg_salary;

    PROCEDURE get_min_salary(dept_id IN INT) AS
        min_salary INT;
    BEGIN
        SELECT MIN(salary) INTO min_salary FROM employees WHERE dept_id = dept_id;
        DBMS_OUTPUT.PUT_LINE('The minimum salary in department ' || dept_id || ' is ' || min_salary);
    END get_min_salary;
END employee_pkg;
/

2. 一个名为"get_min_salary"的存储过程，用于查询指定部门的最低收入，并在屏幕上显示查询信息。该存储过程接受一个部门编号作为参数，不返回结果。存储过程的实现如下：

CREATE OR REPLACE PACKAGE employee_pkg AS
    FUNCTION get_avg_salary(dept_id IN INT) RETURN INT;
    PROCEDURE get_min_salary(dept_id IN INT);
END employee_pkg;
/

CREATE OR REPLACE PACKAGE BODY employee_pkg AS
    FUNCTION get_avg_salary(dept_id IN INT) RETURN INT AS
        avg_salary INT;
    BEGIN
        SELECT AVG(salary) INTO avg_salary FROM employees WHERE dept_id = dept_id;
        RETURN avg_salary;
    END get_avg_salary;

    PROCEDURE get_min_salary(dept_id IN INT) AS
        min_salary INT;
    BEGIN
        SELECT MIN(salary) INTO min_salary FROM employees WHERE dept_id = dept_id;
        DBMS_OUTPUT.PUT_LINE('The minimum salary in department ' || dept_id || ' is ' || min_salary);
    END get_min_salary;
END employee_pkg;
/

可以使用以下语句调用包中的函数和存储过程：

SET SERVEROUTPUT ON;
DECLARE
    avg_salary INT;
BEGIN
    avg_salary := employee_pkg.get_avg_salary(1);
    DBMS_OUTPUT.PUT_LINE('The average salary in department 1 is ' || avg_salary);
    employee_pkg.get_min_salary(1);
END;
/

以上代码将调用"get_avg_salary"函数计算部门1的平均收入，并输出结果。然后，它将调用"get_min_salary"存储过程查询部门1的最低收入，并在屏幕上显示查询信息。