DB API

The Python Database API (DB-API) is a standard specification (PEP 249) that defines a consistent interface for how Python libraries should connect to databases and execute queries - so that code written for one database driver looks and behaves similarly to code written for another.

Core DB-API Objects

• Connection object - represents the connection to the database
• Cursor object - used to execute SQL statements and fetch results

Common DB-API Methods

• connect() - opens a connection to the database
• cursor() - creates a cursor object from a connection
• execute() - runs a SQL statement
• fetchone() / fetchall() - retrieve one row or all rows from the last executed query
• commit() - saves changes made by INSERT, UPDATE, or DELETE statements
• close() - closes the cursor or connection

Example Using sqlite3

import sqlite3

conn = sqlite3.connect("uncodemy.db")
cursor = conn.cursor()
cursor.execute("SELECT first_name FROM customers")
rows = cursor.fetchall()

for row in rows:
    print(row)

conn.close()