作用如题，直接上代码吧，另外还支持 copy一张表的表结构，新建表并获得model对象

# coding: utf-8

import traceback

from sqlalchemy import (BigInteger, Column, DateTime, Integer, MetaData,

                        String, Table, create_engine, text)

from sqlalchemy.ext.declarative import declarative_base

from sqlalchemy.orm import mapper

from sqlalchemy.schema import CreateTable

# 本地数据库

engineLocal = create_engine('mysql+pymysql://root:root@127.0.0.1:3306/lingyun?charset=utf8')

Base = declarative_base()

metadata = MetaData()

def dictToObj(results, to_class):

    """将字典list或者字典转化为指定类的对象list或指定类的对象

    python 支持动态给对象添加属性，所以字典中存在而该类不存在的会直接添加到对应对象

    """

    if isinstance(results, list):

        objL = []

        for result in results:

            obj = to_class()

            for r in result.keys():

                obj.__setattr__(r, result[r])

            objL.append(obj)

        return objL

    else:

        try:

            obj = to_class()

            for r in results.keys():

                obj.__setattr__(r, results[r])

            return obj

        except Exception as e:

            print(e)

            traceback.print_exc()

            return None

    # else:

    #     print("传入对象非字典或者list")

    #     return None

def getModel(name, engine):

    """根据name创建并return一个新的model类

    name:数据库表名

    engine:create_engine返回的对象，指定要操作的数据库连接，from sqlalchemy import create_engine

    """

    Base.metadata.reflect(engine)

    table = Base.metadata.tables[name]

    t = type(name,(object,),dict())

    mapper(t, table)

    Base.metadata.clear()

    return t

def createTableFromTable(name, tableNam, engine):

    """copy一个已有表的结构，并创建新的表

    """

    metadata = MetaData(engine)

    Base.metadata.reflect(engine)

    # 获取原表对象

    table = Base.metadata.tables[tableNam]

    # 获取原表建表语句

    c = str(CreateTable(table))

    # 替换表名

    c = c.replace("CREATE TABLE " + tableNam, "CREATE TABLE if not exists " + name)

    db_conn = engine.connect()

    db_conn.execute(c)

    db_conn.close()

    Base.metadata.clear()

def getNewModel(name, tableNam, engine):

    """copy一个表的表结构并创建新的名为name的表并返回model类

    name:数据库表名

    tableNam:copy的表表名

    engine:create_engine返回的对象，指定要操作的数据库连接，from sqlalchemy import create_engine

    """

    createTableFromTable(name, tableNam, engine)

    return getModel(name, engine)