====== Working with Databases ======

Python supports working with databases like SQLite, MySQL, and PostgreSQL.

=== SQLite ===
It's built into Python, so you don’t need to install anything. It’s great for small, local projects or when you want quick setup without a server.


<code>
import sqlite3

connection = sqlite3.connect("mydatabase.db")
cursor = connection.cursor()
cursor.execute("CREATE TABLE IF NOT EXISTS users (name TEXT, age INTEGER)")
cursor.execute("INSERT INTO users VALUES ('Alice', 25)")
cursor.execute("SELECT * FROM users")

for row in cursor.fetchall():
    print(row)

connection.commit()
connection.close()
</code>

=== MySQL ===

To connect to a MySQL database, you'll first install the mysql connector python package. Then, you can use it to connect to your MySQL server and run standard SQL queries.

//First install//
<code>
pip install mysql-connector-python
</code>

<code>
import mysql.connector

conn = mysql.connector.connect(
    host='localhost',
    user='your_username',
    password='your_password',
    database='your_database'
)

cursor = conn.cursor()
cursor.execute("SELECT * FROM users")
results = cursor.fetchall()

for row in results:
    print(row)

conn.close()

</code>

=== PostgreSQL ===

PostgreSQL is another relational database, often used for complex or large-scale applications. Use the psycopg2 library to connect and interact with it through Python.

//First install//
<code>
pip install psycopg2-binary
</code>

<code>
import psycopg2

conn = psycopg2.connect(
    host='localhost',
    database='your_database',
    user='your_username',
    password='your_password'
)

cursor = conn.cursor()
cursor.execute("SELECT * FROM users")
rows = cursor.fetchall()

for row in rows:
    print(row)

conn.close()
</code>

=== MongoDB (NoSQL – use 'pymongo') ===

If you're working with NoSQL data, MongoDB is a popular choice. Use the pymongo library to connect and interact with collections, which work like JSON objects.

//First install//
<code>
pip install pymongo
</code>

<code>
from pymongo import MongoClient

client = MongoClient("mongodb://localhost:27017/")
db = client["my_database"]
collection = db["users"]

# Insert a document
collection.insert_one({"name": "Alice", "email": "alice@example.com"})

# Find documents
for user in collection.find():
    print(user)

</code>