Dagim H.

task-1/schema.sql

@@ -1 +1,66 @@
--- Write here your DDL statements to create the tables for the database.
+-- Write here your DDL statements to create the tables for the database.
+CREATE TABLE members (
+                         member_id SERIAL PRIMARY KEY,
+                         email TEXT UNIQUE NOT NULL,
+                         name TEXT NOT NULL,
+                         phone TEXT,
+                         address TEXT
+);
+
+CREATE TABLE library_cards (
+                        card_id SERIAL PRIMARY KEY,
+                        card_number TEXT UNIQUE NOT NULL,
+                        issued_on DATE NOT NULL,
+                        expires_on DATE NOT NULL CHECK (expires_on > issued_on),
+                        member_id INT UNIQUE NOT NULL REFERENCES members(member_id)
+);
+
+CREATE TABLE publishers (
+                       publisher_id SERIAL PRIMARY KEY,
+                       name TEXT UNIQUE NOT NULL
+);
+
+CREATE TABLE books (
+                       book_id SERIAL PRIMARY KEY,
+                       isbn TEXT UNIQUE NOT NULL,
+                       title TEXT NOT NULL,
+                       publisher_id INT REFERENCES publishers(publisher_id)
+);
+CREATE TABLE authors (
+                        author_id SERIAL PRIMARY KEY,
+                        name TEXT UNIQUE NOT NULL
+);
+CREATE TABLE book_authors (
+                        book_id INT NOT NULL REFERENCES books(book_id),
+                        author_id INT NOT NULL REFERENCES authors(author_id),
+                        PRIMARY KEY (book_id, author_id)
+);
+CREATE TABLE tags (
+                       tag_id SERIAL PRIMARY KEY,
+                       name TEXT UNIQUE NOT NULL
+);
+CREATE TABLE book_tags (
+                       book_id INT NOT NULL REFERENCES books(book_id),
+                       tag_id INT NOT NULL REFERENCES tags(tag_id),
+                       PRIMARY KEY (book_id, tag_id)
+);
+CREATE TABLE copies (
+                        copy_id SERIAL PRIMARY KEY,
+                        barcode TEXT UNIQUE NOT NULL,
+                        shelf_code TEXT,
+                        book_id INT NOT NULL REFERENCES books(book_id)
+);
+
+CREATE TABLE borrowings (
+                            borrowing_id SERIAL PRIMARY KEY,
+                            copy_id INT NOT NULL REFERENCES copies(copy_id),
+                            member_id INT NOT NULL REFERENCES members(member_id),
+                            borrowed_at TIMESTAMP NOT NULL,
+                            due_date TIMESTAMP NOT NULL,
+                            returned_at TIMESTAMP,
+                            fine_eur NUMERIC DEFAULT 0 CHECK (fine_eur >= 0),
+                            CHECK (returned_at IS NULL OR returned_at >= borrowed_at)
+
+);
+
+

task-2/src/main/java/org/hyf/Main.java

@@ -1,7 +1,204 @@
 package org.hyf;
+import java.sql.Connection;
+import java.sql.SQLException;
+import java.sql.DriverManager;
+import java.sql.ResultSet;
+import java.sql.PreparedStatement;
+
 
 public class Main {
+
+    private static Connection getConnection() throws SQLException {
+        String url = "jdbc:postgresql://localhost:5432/library_db";
+        String user = "postgres";
+        String pass = "postgres";
+        return DriverManager.getConnection(url, user, pass);
+    }
+
+    // Inset Data
+    public  static void insertData() {
+        try (Connection conn = getConnection()) {
+
+            // Publisher 2 rows
+            PreparedStatement pub = conn.prepareStatement(
+                    "INSERT INTO publishers (name) VALUES (?) ON CONFLICT (name) DO NOTHING"
+            );
+            pub.setString(1, "O'Reilly");
+            pub.executeUpdate();
+            pub.setString(1, "Addison-Wesley");
+            pub.executeUpdate();
+
+            // Authors 2 rows
+            PreparedStatement auth = conn.prepareStatement(
+                    "INSERT INTO authors (name) VALUES (?) ON CONFLICT (name) DO NOTHING"
+            );
+
+            //row 1
+            auth.setString(1, "Douglas Crockford");
+            auth.executeUpdate();
+
+            //row 2
+            auth.setString(1, "Eric Freeman");
+            auth.executeUpdate();
+
+            // Books
+            PreparedStatement book = conn.prepareStatement(
+                    "INSERT INTO books (isbn, title, publisher_id) VALUES (?, ?, ?) ON CONFLICT (isbn) DO NOTHING"
+            );
+
+            // row 1
+            book.setString(1, "9780596517748");
+            book.setString(2, "JavaScript: The Good Parts");
+            book.setInt(3, 1);
+            book.executeUpdate();
+
+            // row 2
+            book.setString(1, "9780596007126");
+            book.setString(2, "Head First Design Patterns");
+            book.setInt(3, 1);
+            book.executeUpdate();
+
+
+            // Members
+            PreparedStatement mem = conn.prepareStatement(
+                    "INSERT INTO members (email, name, phone, address) VALUES (?, ?, ?, ?) ON CONFLICT (email) DO NOTHING"
+            );
+
+            //row 1
+            mem.setString(1, "omar@example.com");
+            mem.setString(2, "Omar");
+            mem.setString(3, "+31689012345");
+            mem.setString(4, "Rijnkade 19, Utrecht");
+            mem.executeUpdate();
+
+            //row 2
+            mem.setString(1, "tom@example.com");
+            mem.setString(2, "Tom");
+            mem.setString(3, "+31645678901");
+            mem.setString(4, "Biltstraat 88, Utrecht");
+            mem.executeUpdate();
+
+            // Library Cards
+            PreparedStatement card = conn.prepareStatement(
+                    "INSERT INTO library_cards (card_number, issued_on, expires_on, member_id) VALUES (?, ?, ?, ?) ON CONFLICT (card_number) DO NOTHING"
+            );
+
+            // row 1
+            card.setString(1, "C-1008");
+            card.setDate(2, java.sql.Date.valueOf("2024-01-30"));
+            card.setDate(3, java.sql.Date.valueOf("2027-01-30"));
+            card.setInt(4, 1);
+            card.executeUpdate();
+
+            //row 2
+            card.setString(1, "C-1004");
+            card.setDate(2, java.sql.Date.valueOf("2023-11-20"));
+            card.setDate(3, java.sql.Date.valueOf("2026-11-20"));
+            card.setInt(4, 2);
+            card.executeUpdate();
+
+            // Copies
+            PreparedStatement copy = conn.prepareStatement(
+                    "INSERT INTO copies (barcode, shelf_code, book_id) VALUES (?, ?, ?) ON CONFLICT (barcode) DO NOTHING"
+            );
+
+            // row 1
+            copy.setString(1, "BC-0011");
+            copy.setString(2, "B-03");
+            copy.setInt(3, 1);
+            copy.executeUpdate();
+
+            //row 2
+            copy.setString(1, "BC-0013");
+            copy.setString(2, "B-03");
+            copy.setInt(3, 1);
+            copy.executeUpdate();
+
+            // Borrowings
+            PreparedStatement bor = conn.prepareStatement(
+                    "INSERT INTO borrowings (copy_id, member_id, borrowed_at, due_date, returned_at, fine_eur) " +
+                            "VALUES (?, ?, ?, ?, ?, ?)"
+            );
+
+            // row 1 Omar
+            bor.setInt(1, 1);
+            bor.setInt(2, 1);
+            bor.setTimestamp(3, java.sql.Timestamp.valueOf("2025-12-02 08:08:00"));
+            bor.setTimestamp(4, java.sql.Timestamp.valueOf("2025-12-23 08:08:00"));
+            bor.setTimestamp(5, java.sql.Timestamp.valueOf("2025-12-13 08:08:00"));
+            bor.setBigDecimal(6, new java.math.BigDecimal("0.00"));
+            bor.executeUpdate();
+
+            //row 2 Tom
+            bor.setInt(1, 2);
+            bor.setInt(2, 2);
+            bor.setTimestamp(3, java.sql.Timestamp.valueOf("2026-01-10 08:51:00"));
+            bor.setTimestamp(4, java.sql.Timestamp.valueOf("2026-01-31 08:51:00"));
+            bor.setTimestamp(5, java.sql.Timestamp.valueOf("2026-01-25 08:51:00"));
+            bor.setBigDecimal(6, new java.math.BigDecimal("0.00"));
+            bor.executeUpdate();
+
+            System.out.println("Inserted 2 rows per table.");
+
+        } catch (SQLException e) {
+            e.printStackTrace();
+
+        }
+
+    }
+
+    // Fetch Data
+    public static void fetchData() {
+        String sql = """
+         SELECT 
+           b.title AS book_title,
+           p.name AS publisher_name,
+           c.barcode AS copy_barcode,
+           m.name AS member_name,
+           br.borrowed_at,
+           br.returned_at
+           FROM borrowings br
+           JOIN copies c ON br.copy_id = c.copy_id
+           JOIN books b ON c.book_id = b.book_id
+           JOIN publishers p ON b.publisher_id = p.publisher_id
+           JOIN members m ON br.member_id = m.member_id
+           ORDER BY br.borrowed_at
+           LIMIT 10
+            """;
+
+        try (Connection conn = getConnection();
+             PreparedStatement ps = conn.prepareStatement(sql);
+             ResultSet rs = ps.executeQuery()) {
+
+            System.out.println("\n BORROWING RECORDS ");
+            System.out.println("---------------------------");
+
+            while (rs.next()) {
+                String title = rs.getString("book_title");
+                String publisher = rs.getString("publisher_name");
+                String barcode = rs.getString("copy_barcode");
+                String member = rs.getString("member_name");
+                String borrowedAt = rs.getString("borrowed_at");
+                String returnedAt = rs.getString("returned_at");
+
+                System.out.println(
+                        "Book: " + title +
+                                " | Publisher: " + publisher +
+                                " | Copy: " + barcode +
+                                " | Member: " + member +
+                                " | Borrowed: " + borrowedAt +
+                                " | Returned: " + returnedAt
+                );
+            }
+
+        } catch (SQLException e) {
+            e.printStackTrace();
+        }
+
+    }
+
     public static void main(String[] args) {
-        System.out.println("You code goes here :) You can overwrite this entire method.");
+        insertData();
+        fetchData();
     }
 }