This string‑formatting approach leads to (if input comes from a user) and syntax errors with special characters. A fixed query uses parameter substitution – a safe, maintainable method that also handles escaping automatically.
The order of keys in your dictionary does not need to match the order of columns in the SQL statement. sqlite3 tutorial query python fixed
import sqlite3 # Connect to a database (creates it if it doesn't exist) connection = sqlite3.connect('app_data.db') # Create a cursor object to execute SQL commands cursor = connection.cursor() Use code with caution. 2. The "Fixed" Way to Handle Queries: Parameterization This string‑formatting approach leads to (if input comes
import sqlite3 import os
SQLite3 uses ? as a placeholder. This ensures the library handles escaping and data types for you. import sqlite3 # Connect to a database (creates
import sqlite3 with sqlite3.connect("app_database.db") as connection: cursor = connection.cursor() select_query = "SELECT id, name, salary FROM employees WHERE department = ?;" target_department = ("Engineering",) # Note: Must be a tuple cursor.execute(select_query, target_department) # Option 1: Fetch all results as a list of tuples all_engineers = cursor.fetchall() for row in all_engineers: print(f"ID: row[0] | Name: row[1] | Salary: $row[2]:,.2f") Use code with caution. Improving Readability with sqlite3.Row
# Avoid this approach user_input = "Admin" query = f"SELECT * FROM users WHERE username = 'user_input'" cursor.execute(query) Use code with caution.