"""""""""
Given the following table schemas, how would you figure out the overall attendance rate for each grade on 
2018-03-12? 

Table 1: student_attendance_log
Column Name	        Data Type	Description
date	            string	    date of log per student_id, format is 'yyyy-mm-dd'
student_id	        integer	    id of the student
attendance_status	string	    Possible values are ['present', 'tardy', 'absent']

Table 2: student_demographic
Column Name	    Data Type	    Description
student_id	    integer	        id of the student
grade_level	    integer	        will be a value between 0-12, which corresponds
date_of_birth	string	        Student birth date, format is 'yyyy-mm-dd'
"""


