Project Title: Library Management System
Level: Intermediate
Database: library_db
This project demonstrates the implementation of a Library Management System using SQL. It includes creating and managing tables, performing CRUD operations, and executing advanced SQL queries. The goal is to showcase skills in database design, manipulation, and querying.
- Set up the Library Management System Database: Create and populate the database with tables for branches, employees, members, books, issued status, and return status.
- CRUD Operations: Perform Create, Read, Update, and Delete operations on the data.
- CTAS (Create Table As Select): Utilize CTAS to create new tables based on query results.
- Advanced SQL Queries: Develop complex queries to analyze and retrieve specific data.
- Database Creation: Created a database named
library_db. - Table Creation: Created tables for branches, employees, members, books, issued status, and return status. Each table includes relevant columns and relationships.
CREATE DATABASE library_db;
DROP TABLE IF EXISTS branch;
CREATE TABLE branch
(
branch_id VARCHAR(10) PRIMARY KEY,
manager_id VARCHAR(10),
branch_address VARCHAR(30),
contact_no VARCHAR(15)
);
-- Create table "Employee"
DROP TABLE IF EXISTS employees;
CREATE TABLE employees
(
emp_id VARCHAR(10) PRIMARY KEY,
emp_name VARCHAR(30),
position VARCHAR(30),
salary DECIMAL(10,2),
branch_id VARCHAR(10),
FOREIGN KEY (branch_id) REFERENCES branch(branch_id)
);
-- Create table "Members"
DROP TABLE IF EXISTS members;
CREATE TABLE members
(
member_id VARCHAR(10) PRIMARY KEY,
member_name VARCHAR(30),
member_address VARCHAR(30),
reg_date DATE
);
-- Create table "Books"
DROP TABLE IF EXISTS books;
CREATE TABLE books
(
isbn VARCHAR(50) PRIMARY KEY,
book_title VARCHAR(80),
category VARCHAR(30),
rental_price DECIMAL(10,2),
status VARCHAR(10),
author VARCHAR(30),
publisher VARCHAR(30)
);
-- Create table "IssueStatus"
DROP TABLE IF EXISTS issued_status;
CREATE TABLE issued_status
(
issued_id VARCHAR(10) PRIMARY KEY,
issued_member_id VARCHAR(30),
issued_book_name VARCHAR(80),
issued_date DATE,
issued_book_isbn VARCHAR(50),
issued_emp_id VARCHAR(10),
FOREIGN KEY (issued_member_id) REFERENCES members(member_id),
FOREIGN KEY (issued_emp_id) REFERENCES employees(emp_id),
FOREIGN KEY (issued_book_isbn) REFERENCES books(isbn)
);
-- Create table "ReturnStatus"
DROP TABLE IF EXISTS return_status;
CREATE TABLE return_status
(
return_id VARCHAR(10) PRIMARY KEY,
issued_id VARCHAR(30),
return_book_name VARCHAR(80),
return_date DATE,
return_book_isbn VARCHAR(50),
FOREIGN KEY (return_book_isbn) REFERENCES books(isbn)
);
- Create: Inserted sample records into the
bookstable. - Read: Retrieved and displayed data from various tables.
- Update: Updated records in the
employeestable. - Delete: Removed records from the
memberstable as needed.
Task 1. Create a New Book Record -- "978-1-60129-456-2', 'To Kill a Mockingbird', 'Classic', 6.00, 'yes', 'Harper Lee', 'J.B. Lippincott & Co.')"
INSERT INTO
books(
isbn,
book_title,
category,
rental_price,
status,
author,
publisher
)
VALUES
(
'978-1-60129-456-2',
'To Kill a Mockingbird',
'Classic', 6.00, 'yes',
'Harper Lee',
'J.B. Lippincott & Co.'
);
SELECT
*
FROM
books
;Task 2: Update an Existing Member's Address
UPDATE
members
SET
member_address = '125 Main St'
WHERE
member_id = 'C101'
;Task 3: Delete a Record from the Issued Status Table -- Objective: Delete the record with issued_id = 'IS121' from the issued_status table.
DELETE
FROM
issued_status
WHERE
issued_id = 'IS121'
;Task 4: Retrieve All Books Issued by a Specific Employee -- Objective: Select all books issued by the employee with emp_id = 'E101'.
SELECT
*
FROM
issued_status
WHERE
issued_emp_id = 'E101'
;Task 5: List Members Who Have Issued More Than One Book -- Objective: Use GROUP BY to find members who have issued more than one book.
SELECT
issued_emp_id,
count(issued_id)AS total_book_issued
FROM
issued_status
GROUP BY
issued_emp_id
HAVING COUNT(issued_id) > 1
;- Task 6: Create Summary Tables: Used CTAS to generate new tables based on query results - each book and total book_issued_cnt**
CREATE TABLE
book_cnts
AS
SELECT
b.isbn,
b.book_title,
COUNT(ist.issued_id) as no_issued
FROM
books
AS
b
JOIN
issued_status AS ist
ON
ist.issued_book_isbn = b.isbn
GROUP BY 1,2;
SELECT
*
FROM
book_cnts
;The following SQL queries were used to address specific questions:
Task 7. Retrieve All Books in a Specific Category:
SELECT
*
FROM
books
WHERE
category = 'Classic'
;- Task 8: Find Total Rental Income by Category:
SELECT
b.category,
SUM(b.rental_price),
COUNT(*)
FROM
books
AS
b
JOIN
issued_status AS ist
ON
ist.issued_book_isbn = b.isbn
GROUP BY 1
;- List Members Who Registered in the Last 180 Days:
SELECT
*
FROM
members
WHERE reg_date >= CURRENT_DATE - INTERVAL '180'
;- List Employees with Their Branch Manager's Name and their branch details:
SELECT
e1.*,
b.branch_id,
e2.emp_name as manager
FROM
employees as e1
JOIN
branch AS b
ON
b.branch_id = e1.branch_id
JOIN
employees as e2
ON
b.manager_id = e2.emp_id
;Task 11. Create a Table of Books with Rental Price Above a Certain Threshold:
CREATE TABLE expensive_books AS
SELECT
*
FROM
books
WHERE
rental_price > 7.00;
SELECT * from expensive_books
;Task 12: Retrieve the List of Books Not Yet Returned
SELECT
DISTINCT ist.issued_book_name
FROM
issued_status as ist
LEFT JOIN
return_status as rs
ON
ist.issued_id = rs.issued_id
WHERE
rs.return_id IS NULL
;Task 13: Identify Members with Overdue Books
Write a query to identify members who have overdue books (assume a 30-day return period). Display the member's_id, member's name, book title, issue date, and days overdue.
SELECT
ist.issued_member_id,
m.member_name,
bk.book_title,
ist.issued_date,
CURRENT_DATE - ist.issued_date as over_due_days
FROM
issued_status AS ist
JOIN
members AS m
ON
m.member_id = ist.issued_member_id
JOIN
books as bk
ON
bk.isbn = ist.issued_book_isbn
LEFT JOIN
return_status as rs
ON
rs.issued_id = ist.issued_id
WHERE
rs.return_date IS NULL
AND
(CURRENT_DATE - ist.issued_date) > 420
ORDER BY
1
;Task 14: Update Book Status on Return
Write a query to update the status of books in the books table to "Yes" when they are returned (based on entries in the return_status table).
SELECT
*
FROM
issued_status
WHERE
issued_book_isbn = '978-0-330-25864-8';
-- IS104
SELECT
*
FROM
books
WHERE
isbn = '978-0-451-52994-2';
UPDATE
books
SET status = 'no'
WHERE
isbn = '978-0-451-52994-2';
SELECT
*
FROM
return_status
WHERE
issued_id = 'IS130';
--
INSERT INTO
return_status(return_id, issued_id, return_date, book_quality)
VALUES
(
'RS125',
'IS130',
CURRENT_DATE,
'Good');
SELECT
*
FROM
return_status
WHERE
issued_id = 'IS130';
-- Store Procedures
CREATE OR REPLACE PROCEDURE
add_return_records
(
p_return_id VARCHAR(10),
p_issued_id VARCHAR(10),
p_book_quality VARCHAR(10)
)
LANGUAGE
plpgsql
AS $$
DECLARE
v_isbn VARCHAR(50);
v_book_name VARCHAR(80);
BEGIN
-- all your logic and code
-- inserting into returns based on users input
INSERT INTO
return_status
(
return_id,
issued_id,
return_date,
book_quality
)
VALUES
(
p_return_id,
p_issued_id,
CURRENT_DATE,
p_book_quality
);
SELECT
issued_book_isbn,
issued_book_name
INTO
v_isbn,
v_book_name
FROM
issued_status
WHERE
issued_id = p_issued_id;
UPDATE
books
SET status = 'yes'
WHERE
isbn = v_isbn;
RAISE NOTICE 'Thank you for returning the book: %', v_book_name;
END;
$$
-- Testing FUNCTION add_return_records
issued_id = IS135
ISBN = WHERE isbn = '978-0-307-58837-1'
SELECT
*
FROM
books
WHERE
isbn = '978-0-307-58837-1';
SELECT
*
FROM
issued_status
WHERE
issued_book_isbn = '978-0-307-58837-1';
SELECT
*
FROM
return_status
WHERE
issued_id = 'IS135';
-- calling function
CALL
add_return_records('RS138', 'IS135', 'Good');
-- calling function
CALL
add_return_records('RS148', 'IS140', 'Good');
Task 15: Branch Performance Report
Create a query that generates a performance report for each branch, showing the number of books issued, the number of books returned, and the total revenue generated from book rentals.
SELECT * FROM branch;
SELECT * FROM issued_status;
SELECT * FROM employees;
SELECT * FROM books;
SELECT * FROM return_status;
CREATE TABLE branch_reports
AS
SELECT
b.branch_id,
b.manager_id,
COUNT(ist.issued_id) as number_book_issued,
COUNT(rs.return_id) as number_of_book_return,
SUM(bk.rental_price) as total_revenue
FROM
issued_status as ist
JOIN
employees as e
ON
e.emp_id = ist.issued_emp_id
JOIN
branch as b
ON
e.branch_id = b.branch_id
LEFT JOIN
return_status as rs
ON
rs.issued_id = ist.issued_id
JOIN
books as bk
ON
ist.issued_book_isbn = bk.isbn
GROUP BY
1, 2;
SELECT * FROM branch_reports
;Task 16: CTAS: Create a Table of Active Members
Use the CREATE TABLE AS (CTAS) statement to create a new table active_members containing members who have issued at least one book in the last 2 months.
CREATE TABLE
active_members
AS
SELECT * FROM members
WHERE
member_id IN (
SELECT
DISTINCT
issued_member_id
FROM
issued_status
WHERE
issued_date >= CURRENT_DATE - INTERVAL '2 month'
)
;
SELECT * FROM active_members
;
Task 17: Find Employees with the Most Book Issues Processed
Write a query to find the top 3 employees who have processed the most book issues. Display the employee name, number of books processed, and their branch.
SELECT
e.emp_name,
b.*,
COUNT(ist.issued_id) as no_book_issued
FROM
issued_status as ist
JOIN
employees as e
ON
e.emp_id = ist.issued_emp_id
JOIN
branch as b
ON
e.branch_id = b.branch_id
GROUP BY
1, 2- Database Schema: Detailed table structures and relationships.
- Data Analysis: Insights into book categories, employee salaries, member registration trends, and issued books.
- Summary Reports: Aggregated data on high-demand books and employee performance.
This project demonstrates the application of SQL skills in creating and managing a library management system. It includes database setup, data manipulation, and advanced querying, providing a solid foundation for data management and analysis.
- Set Up the Database: Execute the SQL scripts in the
database_setup.sqlfile to create and populate the database. - Run the Queries: Use the SQL queries in the
analysis_queries.sqlfile to perform the analysis. - Explore and Modify: Customize the queries as needed to explore different aspects of the data or answer additional questions.
This project showcases SQL skills essential for database management and analysis. For more content on SQL and data analysis, connect with me through the following channels:
- GitHub:(https://github.com/Saad-learning)
- LinkedIn: Connect with me professionally
Thank you for your interest in this project!