feat: update structure

cs2102/labs/tutorials/tut05.sql

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+-- How many loans involve
+SELECT b.title
+FROM book b
+WHERE b.isbn13 != ALL (
+    SELECT l.book FROM loan l
+);
+-- 2b
+SELECT s.name
+FROM student s
+WHERE s.email = ANY (
+    SELECT c.owner
+    FROM copy c
+    WHERE (c.owner, c.book, c.copy) NOT IN (
+        SELECT l.owner, l.book, l.copy
+        FROM loan l
+    )
+);
+
+-- 2c (When you see the most/the least, there's a standard way
+-- of solving this
+
+SELECT s.department, s.name, COUNT(*)
+FROM student s, loan l
+WHERE l.owner = s.email
+GROUP BY s.department, s.name, s.email
+HAVING COUNT(*) >= ALL (
+    SELECT COUNT(*)
+    FROM student s1, loan l1
+    WHERE l1.owner = s1.email
+      AND s.department = s1.department
+    GROUP BY s1.email
+)
+ORDER BY COUNT(*) DESC;
+
+-- 2d
+
+SELECT s.name, s.email
+FROM student s
+WHERE s.email = ALL (
+    SELECT c
+    FROM book b
+    WHERE b.authors LIKE '%Adam Smith%'
+    )