display job title and average salary of employees.
SELECT job_title, AVG(salary) FROM employees AS T1 JOIN jobs AS T2 ON T1.job_id = T2.job_id GROUP BY T2.job_title
``` yaml
jobs: # name of dataframe
- JOB_ID:
    dtype: string
    sample_values: AD_PRES, AD_VP, AD_ASST
- JOB_TITLE:
    dtype: string
    sample_values: President, Administration Vice President, Administration Assistant
- MIN_SALARY:
    dtype: int64
    sample_values: 20000, 15000, 3000
- MAX_SALARY:
    dtype: int64
    sample_values: 40000, 30000, 6000

employees: # name of dataframe
- EMPLOYEE_ID:
    dtype: int64
    sample_values: 100, 101, 102
- FIRST_NAME:
    dtype: string
    sample_values: Steven, Neena, Lex
- LAST_NAME:
    dtype: string
    sample_values: King, Kochhar, De Haan
- EMAIL:
    dtype: string
    sample_values: SKING, NKOCHHAR, LDEHAAN
- PHONE_NUMBER:
    dtype: string
    sample_values: 515.123.4567, 515.123.4568, 515.123.4569
- HIRE_DATE:
    dtype: datetime
    sample_values: 1987-06-17, 1987-06-18, 1987-06-19
- JOB_ID:
    dtype: string
    sample_values: AD_PRES, AD_VP, AD_VP
- SALARY:
    dtype: int64
    sample_values: 24000, 17000, 17000
- COMMISSION_PCT:
    dtype: float64
    sample_values: 0.0, 0.0, 0.0
- MANAGER_ID:
    dtype: int64
    sample_values: 0, 100, 100
- DEPARTMENT_ID:
    dtype: int64
    sample_values: 90, 90, 90

```
Foreign Key constraints:
Column 'job_id' in dataframe 'employees' has a foreign key relation to column 'job_id' in dataframe 'jobs'.

JOB_TITLE,AVG(salary)
Accountant,7920.0
Accounting Manager,12000.0
Administration Assistant,4400.0
Administration Vice President,17000.0
Finance Manager,12000.0
Human Resources Representative,6500.0
Marketing Manager,13000.0
Marketing Representative,6000.0
President,24000.0
Programmer,5760.0
Public Accountant,8300.0
Public Relations Representative,10000.0
Purchasing Clerk,2780.0
Purchasing Manager,11000.0
Sales Manager,12200.0
Sales Representative,8350.0
Shipping Clerk,3215.0
Stock Clerk,2785.0
Stock Manager,7280.0
