Table schema:
CREATE TABLE department (dept_name VARCHAR, dept_code VARCHAR); CREATE TABLE student (stu_gpa INTEGER, dept_code VARCHAR)

Question: What is the name and the average gpa of department whose students have the highest average gpa?
SQL: SELECT T2.dept_name, AVG(T1.stu_gpa) FROM student AS T1 JOIN department AS T2 ON T1.dept_code = T2.dept_code GROUP BY T1.dept_code ORDER BY AVG(T1.stu_gpa) DESC LIMIT 1