Task: Text to Code
Input (English): Step 1: For each row in department table, find corresponding rows in instructor table and in student table.
Step 2: find the summation of tot_cred of each value of instructor's name in the results of step 1.
Step 3: find instructor's name of the results of step 1 with largest value in the results of step 2
Output (English): SELECT T2.name FROM department AS T1 JOIN instructor AS T2 ON T2.dept_name = T1.dept_name JOIN student AS T3 ON T1.dept_name = T3.dept_name GROUP BY T2.name ORDER BY Sum ( T3.tot_cred ) Desc LIMIT 1