What is the sum of year 1 and year 2 students?
year 1 and year 2 students refers to yearsInProgram = 'Year_1' and yearsInProgram = 'Year_2' and student = 1
SELECT COUNT(*) FROM person WHERE yearsInProgram = 'Year_1' OR yearsInProgram = 'Year_2'
database name:db_id computer_student
course table course Cols: course id dtype integer, course level dtype text, 
person table person Cols: person ID dtype integer, professor dtype integer, student dtype integer, has position dtype text, in phase dtype text, years in program dtype text, 
advisedBy table advisedBy Cols: person id dtype integer, person id dummy dtype integer, 
taughtBy table taughtBy Cols: course ID dtype integer, person ID dtype integer, 
