CREATE TABLE employees (EMPLOYEE_ID NUMBER, FIRST_NAME VARCHAR2, LAST_NAME VARCHAR2, EMAIL VARCHAR2, PHONE_NUMBER VARCHAR2, HIRE_DATE DATE, JOB_ID VARCHAR2, SALARY NUMBER, COMMISSION_PCT NUMBER, MANAGER_ID NUMBER, DEPARTMENT_ID NUMBER)
CREATE TABLE locations (LOCATION_ID NUMBER, STREET_ADDRESS VARCHAR2, POSTAL_CODE VARCHAR2, CITY VARCHAR2, STATE_PROVINCE VARCHAR2, COUNTRY_ID VARCHAR2)
CREATE TABLE countries (COUNTRY_ID VARCHAR2, COUNTRY_NAME VARCHAR2, REGION_ID NUMBER)
CREATE TABLE job_history (EMPLOYEE_ID NUMBER, START_DATE DATE, END_DATE DATE, JOB_ID VARCHAR2, DEPARTMENT_ID NUMBER)
CREATE TABLE departments (DEPARTMENT_ID NUMBER, DEPARTMENT_NAME VARCHAR2, MANAGER_ID NUMBER, LOCATION_ID NUMBER)
CREATE TABLE jobs (JOB_ID VARCHAR2, JOB_TITLE VARCHAR2, MIN_SALARY NUMBER, MAX_SALARY NUMBER)
CREATE TABLE regions (REGION_ID NUMBER, REGION_NAME VARCHAR2)

Show the average salary by each hire date of employees, and please bin the hire date into the Month interval for showing a bar chart, list from high to low by the mean salary.
SELECT HIRE_DATE, AVG(SALARY) FROM employees ORDER BY AVG(SALARY) DESC
SELECT "HIRE_DATE", AVG("SALARY") FROM "employees" ORDER BY AVG("SALARY") DESC