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Python Code Samples

Copy-ready Python snippets by topic and difficulty — short, focused, and runnable in the browser editor.

4 matches
Files & data easy

Parameterize SQL queries in Python to prevent SQL injection

Safely fetch users from a SQLite database using parameterized queries to prevent SQL injection attacks.

sqlite3 sql injection parameterized query
Python 
import sqlite3

def get_users_by_name(name):
    """Fetch users safely using parameterized query."""
    conn = sqlite3.connect(':memory:')
    cursor = conn.cursor()
    
    # Create sample table and data
    cursor.execute('CREATE TABLE users (id INTEGER, name TEXT)')
    cursor.executemany('INSERT INTO users (name…
15 0 Open
Files & data easy

Read SQLite database with sqlite3 module in Python

Connect to a SQLite database and query rows with the standard library sqlite3 module, returning results as dictionaries.

sqlite database stdlib
Python 
import sqlite3
from pathlib import Path

# Create an in-memory database and a sample table
connection = sqlite3.connect(":memory:")
cursor = connection.cursor()

cursor.execute("""
CREATE TABLE employees (
    id INTEGER PRIMARY KEY,
    name TEXT NOT NULL,
    department TEXT NOT NULL,
    salary REAL
)
""")

# Inser…
17 0 Open
Automation & scripting easy

How to Backup an SQLite Database with a Timestamp in Python

Backs up an SQLite database file to a timestamped copy using the sqlite3 backup API.

sqlite backup automation
Python 
import sqlite3
import shutil
from datetime import datetime
from pathlib import Path

def backup_database(db_path: str, backup_dir: str = "backups") -> Path:
    db = Path(db_path)
    backup_folder = Path(backup_dir)
    backup_folder.mkdir(exist_ok=True)
    
    timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
 …
13 0 Open
Database scaling & optimization medium

How to Mock SQLite executemany When Batch Inserting in Python

Batch insert many rows into SQLite with executemany and mock the cursor for isolated tests.

sqlite3 executemany mock
Python 
import sqlite3
from unittest.mock import Mock, patch

def insert_users(conn, users):
    """Insert multiple user records using executemany."""
    cursor = conn.cursor()
    cursor.executemany(
        "INSERT INTO users (name, age) VALUES (?, ?)",
        users
    )
    conn.commit()
    return cursor.rowcount

if _…
15 0 Open

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PythonSkillset code samples are short, focused examples organised by topic and difficulty. Every snippet is server-rendered HTML — readable by search engines and easy to copy. Open any sample, read the notes, copy the code, then press Try in editor to run it in the browser with Pyodide.

How to use this library

  1. Pick a topic section — strings, lists, files, functions, and more
  2. Open a sample, read How it works, and copy the code block
  3. Run it in the IDE, tweak values, then take a related quiz or tutorial lesson

Samples vs tutorials and challenges

Samples are quick reference — one concept per page. For step-by-step teaching, use our Python tutorials. To test yourself, try quizzes or coding challenges. Clean up style with the Python formatter.

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