SQLAlchemy核心:将三列合并为一列

from sqlalchemy import create_engine, select, func
from sqlalchemy.orm import sessionmaker
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import Column, Integer, String

# 创建数据库连接
engine = create_engine('数据库连接字符串')

# 创建会话
Session = sessionmaker(bind=engine)
session = Session()

# 定义数据模型
Base = declarative_base()

class MyTable(Base):
    __tablename__ = 'my_table'
    id = Column(Integer, primary_key=True)
    column1 = Column(String)
    column2 = Column(String)
    column3 = Column(String)

# 查询并将三列合并为一列
query = session.query(func.concat(MyTable.column1, MyTable.column2, MyTable.column3).label('merged_column'))
result = query.all()

# 打印结果
for row in result:
    print(row.merged_column)