CREATE TABLE takes (ID VARCHAR2, course_id VARCHAR2, sec_id VARCHAR2, semester VARCHAR2, year NUMBER, grade VARCHAR2)
CREATE TABLE section (course_id VARCHAR2, sec_id VARCHAR2, semester VARCHAR2, year NUMBER, building VARCHAR2, room_number VARCHAR2, time_slot_id VARCHAR2)
CREATE TABLE student (ID VARCHAR2, name VARCHAR2, dept_name VARCHAR2, tot_cred NUMBER)
CREATE TABLE time_slot (time_slot_id VARCHAR2, day VARCHAR2, start_hr NUMBER, start_min NUMBER, end_hr NUMBER, end_min NUMBER)
CREATE TABLE classroom (building VARCHAR2, room_number VARCHAR2, capacity NUMBER)
CREATE TABLE course (course_id VARCHAR2, title VARCHAR2, dept_name VARCHAR2, credits NUMBER)
CREATE TABLE instructor (ID VARCHAR2, name VARCHAR2, dept_name VARCHAR2, salary NUMBER)
CREATE TABLE advisor (s_ID VARCHAR2, i_ID VARCHAR2)
CREATE TABLE department (dept_name VARCHAR2, building VARCHAR2, budget NUMBER)
CREATE TABLE prereq (course_id VARCHAR2, prereq_id VARCHAR2)
CREATE TABLE teaches (ID VARCHAR2, course_id VARCHAR2, sec_id VARCHAR2, semester VARCHAR2, year NUMBER)

Bar chart x axis building y axis maximal capacity, and sort in desc by the total number.
SELECT building, MAX(capacity) FROM classroom GROUP BY building ORDER BY MAX(capacity) DESC
SELECT "building", MAX("capacity") FROM "classroom" GROUP BY "building" ORDER BY MAX("capacity") DESC