#PyQt5 #SQLite #DesktopApp #Pharmacy #Barcode #Python

Lesson: Building a Pharmacy Management System with PyQt5 and Barcode Scanning

This tutorial will guide you through creating a complete desktop application for managing a pharmacy. The system will use a SQLite database for inventory, and a Point of Sale (POS) interface that uses barcode scanning to add drugs to a sale and automatically deducts stock upon completion.

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#Step 1: Database Setup (database.py)

First, we create a dedicated file to handle all SQLite database operations. This keeps our data logic separate from our UI logic. Create a file named database.py.

import sqlite3

DB_NAME = 'pharmacy.db'

def connect():
    return sqlite3.connect(DB_NAME)

def setup_database():
    conn = connect()
    cursor = conn.cursor()
    cursor.execute('''
        CREATE TABLE IF NOT EXISTS drugs (
            id INTEGER PRIMARY KEY AUTOINCREMENT,
            name TEXT NOT NULL,
            barcode TEXT NOT NULL UNIQUE,
            quantity INTEGER NOT NULL,
            price REAL NOT NULL,
            expiry_date TEXT NOT NULL
        )
    ''')
    conn.commit()
    conn.close()

def add_drug(name, barcode, quantity, price, expiry_date):
    conn = connect()
    cursor = conn.cursor()
    try:
        cursor.execute("INSERT INTO drugs (name, barcode, quantity, price, expiry_date) VALUES (?, ?, ?, ?, ?)",
                       (name, barcode, quantity, price, expiry_date))
        conn.commit()
    except sqlite3.IntegrityError:
        return False # Barcode already exists
    finally:
        conn.close()
    return True

def get_all_drugs():
    conn = connect()
    cursor = conn.cursor()
    cursor.execute("SELECT id, name, barcode, quantity, price, expiry_date FROM drugs ORDER BY name")
    drugs = cursor.fetchall()
    conn.close()
    return drugs

def find_drug_by_barcode(barcode):
    conn = connect()
    cursor = conn.cursor()
    cursor.execute("SELECT id, name, barcode, quantity, price, expiry_date FROM drugs WHERE barcode = ?", (barcode,))
    drug = cursor.fetchone()
    conn.close()
    return drug

def update_drug_quantity(drug_id, sold_quantity):
    conn = connect()
    cursor = conn.cursor()
    cursor.execute("UPDATE drugs SET quantity = quantity - ? WHERE id = ?", (sold_quantity, drug_id))
    conn.commit()
    conn.close()

# Hashtags: #SQLite #DatabaseDesign #DataPersistence #Python

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#Step 2: Main Application and Inventory Management UI

Create the main application file, main.py. We will set up the main window with tabs for "Point of Sale" and "Inventory Management". We will fully implement the inventory tab first, allowing users to view and add drugs to the database.