diff --git a/python.md b/python.md index 52fd2f1..97dd038 100644 --- a/python.md +++ b/python.md @@ -15,6 +15,17 @@ 11. [File Handling](#file-handling) 12. [Exception Handling](#exception-handling) 13. [Classes and Objects](#classes-and-objects) +14. [SQLite3 Database Connection](#sqlite3-database-connection) + 14.1 [Connecting to a Database](#connecting-to-a-database) + 14.2 [Creating a Table](#creating-a-table) + 14.3 [Inserting Data](#inserting-data) + 14.4 [Querying Data](#querying-data) + 14.5 [Updating Data](#updating-data) + 14.6 [Deleting Data](#deleting-data) + 14.7 [Closing the Connection](#closing-the-connection) +15. [JSON Data Connection](#json-data-connection) + 15.1 [Loading JSON Data](#loading-json-data) + 15.2 [Writing JSON Data](#writing-json-data) ## Variables @@ -214,5 +225,123 @@ obj = MyClass("John") obj.say_hello() # Outputs: Hello, John! ``` +## Working with Data + +```python +# Import necessary modules +import sqlite3 +import json ``` +## 14. SQLite3 Database Connection + +### 14.1 Connecting to a Database + +```python +# Connect to a database (creates a new database if it doesn't exist) +conn = sqlite3.connect('example.db') + +# Create a cursor object to execute SQL commands +cursor = conn.cursor() +``` + +### 14.2 Creating a Table + +```python +# Create a table +cursor.execute(''' + CREATE TABLE IF NOT EXISTS users ( + id INTEGER PRIMARY KEY, + username TEXT NOT NULL, + email TEXT NOT NULL + ) +''') + +# Commit the changes +conn.commit() +``` + +### 14.3 Inserting Data + +```python +# Insert data into the table +cursor.execute(''' + INSERT INTO users (username, email) + VALUES ('john_doe', 'john@example.com') +''') + +# Commit the changes +conn.commit() +``` + +### 14.4 Querying Data + +```python +# Fetch all rows from the table +cursor.execute('SELECT * FROM users') +rows = cursor.fetchall() + +# Print the results +for row in rows: + print(row) +``` + +### 14.5 Updating Data + +```python +# Update data in the table +cursor.execute(''' + UPDATE users + SET email = 'john.doe@example.com' + WHERE username = 'john_doe' +''') + +# Commit the changes +conn.commit() +``` + +### 14.6 Deleting Data + +```python +# Delete data from the table +cursor.execute(''' + DELETE FROM users + WHERE username = 'john_doe' +''') + +# Commit the changes +conn.commit() +``` + +### 14.7 Closing the Connection + +```python +# Close the cursor and connection when done +cursor.close() +conn.close() +``` + +## 15. JSON Data Connection + +### 15.1 Loading JSON Data + +```python +# Load JSON data from a file +with open('data.json', 'r') as json_file: + data = json.load(json_file) + print(data) +``` + +### 15.2 Writing JSON Data + +```python +# Write Python data to a JSON file +data_to_write = {'name': 'John', 'age': 30, 'city': 'New York'} + +with open('output.json', 'w') as json_file: + json.dump(data_to_write, json_file) +``` + +``` + +