updated to mysql-connector-python

README.md

@@ -6,41 +6,41 @@ Tables 9.3–9.5 (STUDENT, GUARDIAN, ATTENDANCE).
 
 ## What it does on startup
 
-1. Connects to the MySQL server at `10.0.1.40:3306`.
+1. Connects to the MySQL server at `10.10.0.160:3306`.
 2. Verifies the `student_db` database exists — creates it if not.
 3. Verifies the `GUARDIAN`, `STUDENT`, and `ATTENDANCE` tables exist
-   (in that order, since STUDENT references GUARDIAN and ATTENDANCE
+	(in that order, since STUDENT references GUARDIAN and ATTENDANCE
-   references STUDENT) — creates any that are missing, with the exact
+	references STUDENT) — creates any that are missing, with the exact
-   data types and constraints from the schema (primary keys, foreign
+	data types and constraints from the schema (primary keys, foreign
-   keys, `NOT NULL`, `UNIQUE` on `GPhone`, and the composite primary key
+	keys, `NOT NULL`, `UNIQUE` on `GPhone`, and the composite primary key
-   `(AttendanceDate, RollNumber)` on ATTENDANCE).
+	`(AttendanceDate, RollNumber)` on ATTENDANCE).
 4. Launches an interactive menu for Create / Read / Update / Delete.
 
 ## Setup
 
 1. Install the one dependency:
 
-   ```bash
+	```bash
-   pip install -r requirements.txt
+	pip install -r requirements.txt
-   ```
+	```
 
 2. Set your MySQL credentials as environment variables (the host/port/
-   database default to the assignment's values already):
+	database default to the assignment's values already):
 
-   ```bash
+	```bash
-   export DB_USER=root
+	export DB_USER=root
-   export DB_PASSWORD=your_password_here
+	export DB_PASSWORD=your_password_here
-   # optional overrides — these already default correctly:
+	# optional overrides — these already default correctly:
-   # export DB_HOST=10.0.1.40
+	# export DB_HOST=10.10.0.160
-   # export DB_PORT=3306
+	# export DB_PORT=3306
-   # export DB_NAME=student_db
+	# export DB_NAME=student_db
-   ```
+	```
 
 3. Run it:
 
-   ```bash
+	```bash
-   python3 main.py
+	python3 main.py
-   ```
+	```
 
 ## Files
 
@@ -72,12 +72,6 @@ cascades and removes their attendance records automatically.
 
 ## Notes
 
-- Uses [PyMySQL](https://pymysql.readthedocs.io/), a pure-Python MySQL
+- Uses [mysql-connector-python](https://dev.mysql.com/doc/connector-python/en/), Oracle's official pure-Python MySQL driver — no system libraries (like `libmysqlclient`) required.
-  client — no system libraries (like `libmysqlclient`) required.
+- All input is validated against the schema's constraints (max lengths, digit counts, date format, P/A status) before hitting the database, and database-level errors (duplicate keys, foreign key violations) are caught and shown as friendly messages rather than crashing.
-- All input is validated against the schema's constraints (max lengths,
+- Tested end-to-end (connect → create DB/tables → full CRUD → constraint error handling → cascade delete) against a local MySQL/MariaDB instance before delivery.
-  digit counts, date format, P/A status) before hitting the database,
-  and database-level errors (duplicate keys, foreign key violations)
-  are caught and shown as friendly messages rather than crashing.
-- Tested end-to-end (connect → create DB/tables → full CRUD → constraint
-  error handling → cascade delete) against a local MySQL/MariaDB
-  instance before delivery.

config.py

@@ -5,12 +5,17 @@ Connection settings are read from environment variables first, falling back
 to the defaults below (which match the assignment's requirements). This
 means you can run the app as-is, or override any value like:
 
-    DB_HOST=10.0.1.40 DB_USER=root DB_PASSWORD=secret python3 main.py
+	DB_HOST=10.10.0.160 DB_USER=root DB_PASSWORD=secret python3 main.py
+
+	# on windows
+	$env:DB_USER="mysql_user"
+	$env:DB_PASSWORD="mysql_password"
+	python3 main.py
 """
 
 import os
 
-DB_HOST = os.environ.get("DB_HOST", "10.0.1.40")
+DB_HOST = os.environ.get("DB_HOST", "10.10.0.160")
 DB_PORT = int(os.environ.get("DB_PORT", "3306"))
 DB_USER = os.environ.get("DB_USER", "root")
 DB_PASSWORD = os.environ.get("DB_PASSWORD", "")

crud.py

@@ -1,12 +1,12 @@
 """
 CRUD operations for GUARDIAN, STUDENT and ATTENDANCE.
 
-Every function takes an open pymysql connection as its first argument and
+Every function takes an open mysql-connector-python connection as its first
-manages its own commit/rollback. All functions return plain data
+argument and manages its own commit/rollback. All functions return plain
-(dicts/lists/bool) so this module has no dependency on the UI layer.
+data (dicts/lists/bool) so this module has no dependency on the UI layer.
 """
 
-import pymysql
+import mysql.connector
 
 
 class CrudError(Exception):
@@ -20,33 +20,34 @@ def _run(conn, sql, params=None, fetch=None):
 	fetch: None (no fetch), 'one', or 'all'
 	Translates common MySQL errors into CrudError with a friendly message.
 	"""
+	cur = conn.cursor(dictionary=True)
 	try:
-		with conn.cursor() as cur:
+		cur.execute(sql, params or ())
-			cur.execute(sql, params or ())
+		result = None
-			result = None
+		if fetch == "one":
-			if fetch == "one":
+			result = cur.fetchone()
-				result = cur.fetchone()
+		elif fetch == "all":
-			elif fetch == "all":
+			result = cur.fetchall()
-				result = cur.fetchall()
+		conn.commit()
-			conn.commit()
+		return result if fetch else cur.rowcount
-			return result if fetch else cur.rowcount
+	except mysql.connector.errors.IntegrityError as e:
-	except pymysql.err.IntegrityError as e:
 		conn.rollback()
-		code = e.args[0] if e.args else None
+		if e.errno == 1062:
-		if code == 1062:
 			raise CrudError("A record with that primary/unique key already exists.")
-		if code in (1451, 1452):
+		if e.errno in (1451, 1452):
 			raise CrudError(
 				"That operation violates a foreign key constraint "
 				"(referenced record missing, or still referenced by other rows)."
 			)
 		raise CrudError(f"Database integrity error: {e}")
-	except pymysql.err.DataError as e:
+	except mysql.connector.errors.DataError as e:
 		conn.rollback()
 		raise CrudError(f"Invalid data for one or more fields: {e}")
-	except pymysql.err.MySQLError as e:
+	except mysql.connector.Error as e:
 		conn.rollback()
 		raise CrudError(f"Database error: {e}")
+	finally:
+		cur.close()
 
 
 # ---------------------------------------------------------------- GUARDIAN --

db.py

@@ -13,8 +13,8 @@ Schema notes:
 
 import sys
 
-import pymysql
+import mysql.connector
-import pymysql.cursors
+from mysql.connector import errorcode
 
 import config
 
@@ -61,20 +61,25 @@ TABLE_ORDER = ["GUARDIAN", "STUDENT", "ATTENDANCE"]
 def connect_server(database=None):
 	"""Connect to the MySQL server (optionally selecting a database)."""
 	try:
-		conn = pymysql.connect(
+		conn = mysql.connector.connect(
 			host=config.DB_HOST,
 			port=config.DB_PORT,
 			user=config.DB_USER,
 			password=config.DB_PASSWORD,
 			database=database,
-			connect_timeout=config.DB_CONNECT_TIMEOUT,
+			connection_timeout=config.DB_CONNECT_TIMEOUT,
-			cursorclass=pymysql.cursors.DictCursor,
 			autocommit=False,
 		)
 		return conn
-	except pymysql.err.OperationalError as e:
+	except mysql.connector.Error as e:
-		print(f"\n[ERROR] Could not connect to MySQL server at "
+		if e.errno == errorcode.ER_ACCESS_DENIED_ERROR:
-			  f"{config.DB_HOST}:{config.DB_PORT} as user '{config.DB_USER}'.")
+			print(f"\n[ERROR] Access denied for user '{config.DB_USER}' — check "
+				  f"DB_USER/DB_PASSWORD.")
+		elif database and e.errno == errorcode.ER_BAD_DB_ERROR:
+			print(f"\n[ERROR] Database '{database}' does not exist.")
+		else:
+			print(f"\n[ERROR] Could not connect to MySQL server at "
+				  f"{config.DB_HOST}:{config.DB_PORT} as user '{config.DB_USER}'.")
 		print(f"        Details: {e}")
 		sys.exit(1)
 
@@ -83,7 +88,8 @@ def ensure_database():
 	"""Verify the student_db database exists; create it if it does not."""
 	conn = connect_server(database=None)
 	try:
-		with conn.cursor() as cur:
+		cur = conn.cursor()
+		try:
 			cur.execute("SHOW DATABASES LIKE %s", (config.DB_NAME,))
 			exists = cur.fetchone() is not None
 			if exists:
@@ -96,23 +102,29 @@ def ensure_database():
 				)
 				conn.commit()
 				print(f"[OK] Database '{config.DB_NAME}' created.")
+		finally:
+			cur.close()
 	finally:
 		conn.close()
 
 
 def ensure_tables(conn):
 	"""Verify each required table exists; create any that are missing."""
-	with conn.cursor() as cur:
+	cur = conn.cursor()
-		cur.execute("SHOW TABLES")
+	cur.execute("SHOW TABLES")
-		existing = {row[f"Tables_in_{config.DB_NAME}"] for row in cur.fetchall()}
+	existing = {row[0] for row in cur.fetchall()}
+	cur.close()
 
 	for table in TABLE_ORDER:
 		if table in existing:
 			print(f"[OK] Table '{table}' found.")
 		else:
 			print(f"[..] Table '{table}' not found. Creating it...")
-			with conn.cursor() as cur:
+			cur = conn.cursor()
+			try:
 				cur.execute(TABLE_DEFINITIONS[table])
+			finally:
+				cur.close()
 			conn.commit()
 			print(f"[OK] Table '{table}' created.")
 

main.py

@@ -3,7 +3,7 @@
 Student Management System
 ==========================
 Terminal CRUD application for STUDENT / GUARDIAN / ATTENDANCE, backed by
-MySQL on 10.0.1.40:3306 (student_db).
+MySQL on 10.10.0.160:3306 (student_db).
 
 On startup this:
   1. Connects to the MySQL server.
@@ -17,7 +17,7 @@ Run:
 
 import sys
 
-import pymysql
+import mysql.connector
 
 import crud
 import db
@@ -326,7 +326,7 @@ def main():
 		main_menu(conn)
 	except KeyboardInterrupt:
 		print("\n\nInterrupted. Exiting.")
-	except pymysql.err.MySQLError as e:
+	except mysql.connector.Error as e:
 		print(f"\n[ERROR] Lost database connection: {e}")
 		sys.exit(1)
 	finally:

requirements.txt

@@ -1 +1 @@
-PyMySQL>=1.1.0
+mysql-connector-python>=9.0.0