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Days-23-26.md

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+### **Day 23: Database Connection**
+Python can connect to various types of databases using different database libraries. One common library for working with databases in Python is `sqlite3` for SQLite databases.
+
+- **Connecting to a Database:**
+  - Use the `sqlite3.connect()` method to connect to a database.
+  - This method creates a new database if it doesn't exist or opens an existing one.
+
+**Example of connecting to an SQLite database:**
+```python
+import sqlite3
+
+# Connect to a database (creates a new one if it doesn't exist)
+conn = sqlite3.connect("my_database.db")
+
+# Create a cursor object to execute SQL commands
+cursor = conn.cursor()
+
+# Close the connection when done
+conn.close()
+```
+
+### **Day 24: Creating Tables and Inserting Data**
+You can create tables in a database and insert data into them using SQL commands.
+
+- **Creating Tables:**
+  - Use the `execute()` method to run SQL CREATE TABLE queries.
+- **Inserting Data:**
+  - Use the `execute()` method to run SQL INSERT queries.
+
+**Example of creating a table and inserting data:**
+```python
+import sqlite3
+
+conn = sqlite3.connect("my_database.db")
+cursor = conn.cursor()
+
+# Create a table
+cursor.execute("""
+    CREATE TABLE IF NOT EXISTS students (
+        id INTEGER PRIMARY KEY,
+        name TEXT,
+        age INTEGER
+    )
+""")
+
+# Insert data into the table
+cursor.execute("INSERT INTO students (name, age) VALUES (?, ?)", ("Alice", 25))
+cursor.execute("INSERT INTO students (name, age) VALUES (?, ?)", ("Bob", 30))
+
+# Commit the changes and close the connection
+conn.commit()
+conn.close()
+```
+
+### **Day 25: Querying Data**
+You can retrieve data from a database table using SQL SELECT queries.
+
+- **Querying Data:**
+  - Use the `execute()` method to run SQL SELECT queries.
+  - Use the `fetchall()` method to retrieve all rows from a query.
+
+**Example of querying data from a table:**
+```python
+import sqlite3
+
+conn = sqlite3.connect("my_database.db")
+cursor = conn.cursor()
+
+# Query data from the table
+cursor.execute("SELECT * FROM students")
+students = cursor.fetchall()
+
+# Print the results
+for student in students:
+    print(f"ID: {student[0]}, Name: {student[1]}, Age: {student[2]}")
+
+conn.close()
+```
+
+### **Day 26: Updating and Deleting Data**
+You can use SQL UPDATE and DELETE queries to modify or remove data from a database table.
+
+- **Updating Data:**
+  - Use SQL UPDATE queries to modify existing data.
+- **Deleting Data:**
+  - Use SQL DELETE queries to remove data from the table.
+
+**Example of updating and deleting data:**
+```python
+import sqlite3
+
+conn = sqlite3.connect("my_database.db")
+cursor = conn.cursor()
+
+# Update data
+cursor.execute("UPDATE students SET age = 26 WHERE name = 'Alice'")
+
+# Delete data
+cursor.execute("DELETE FROM students WHERE name = 'Bob'")
+
+# Commit the changes and close the connection
+conn.commit()
+conn.close()
+```
+
+Understanding how to work with databases and SQL in Python is crucial for many real-world applications where data storage and retrieval are required. The `sqlite3` library is suitable for learning and small-scale projects, but for larger databases, you may consider other database systems like MySQL or PostgreSQL. Practice with these examples to become proficient in database operations in Python.