Operaciones Atómicas
- Create: INSERT INTO...
- Read: SELECT * FROM...
- Update: UPDATE ... SET ... WHERE ...
- Delete: DELETE FROM ... WHERE ...
Evitando SQL Injection
# MODO SEGURO: Usando parámetros (placeholders)
cursor.execute("SELECT * FROM usuarios WHERE email = ?", (email_user,))
# ¡NUNCA concatenar strings directamente!