sqlalchemy根据表名动态创建model类
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)
https://blog.csdn.net/j_object/article/details/80118657