


Navigate the sea of data: Python SQLAlchemy takes you on a journey of data
python sqlAlchemy is a popular Python Object Relational Mapping (ORM) library, which is a powerful tool for interacting between Python and relational databases. SQLAlchemy allows developers to use Python objects to manipulate relational databases, thereby simplifying database operations and reducing the need to write SQL queries.
1. Main advantages:
- Intuition: SQLAlchemy uses Python objects to represent tables and rows in the database, which makes operating the database more intuitive and easy to understand.
- Security: SQLAlchemy uses precompiled SQL queries to effectively prevent SQL injection attacks.
- Efficiency: SQLAlchemy uses lazy loading to reduce unnecessary database queries and thereby improve performance.
- Portability: SQLAlchemy supports a variety of relational databases, including Mysql, postgresql, oracle and SQLite, making it highly portable .
2. Install SQLAlchemy:
SQLAlchemy can be installed via:
from sqlalchemy import create_engine, Column, Integer, String from sqlalchemy.orm import sessionmaker # 创建 Engine 实例 engine = create_engine("sqlite:///mydb.db") # 创建 Session 实例 Session = sessionmaker(bind=engine) session = Session() # 创建 User 表 class User(Base): __tablename__ = "user" id = Column(Integer, primary_key=True) name = Column(String(50)) # 向 User 表中插入数据 session.add(User(name="John Doe")) # 提交事务 session.commit() # 关闭 Session 实例 session.close()
4. Advanced usage:
SQLAlchemy also provides many advanced features, including relationships, inheritance, polymorphism, and more. By using these features, developers can build more complex data models and perform more advanced database operations.
5. Summary:
SQLAlchemy is a powerful ORM library that can help developers simplify database operations and improve development efficiency. By using SQLAlchemy, developers can focus on business logic without worrying about underlying database operations.
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