我的問題是:如何通過動態過濾器動態更新數據庫中的值。我想對列名保持不可知。我希望用戶通過過濾器來定位行和要更改的字段的表達式。這個想法是創建一個通用函數來做到這一點。我在理解如何為此使用 set 屬性時遇到問題,或者還有其他方法?謝謝進口:from sqlalchemy.orm import ( mapper, relationship, sessionmaker)from sqlalchemy import *數據庫啟動和連接initation = 'mysql+pymysql://user:password@localhost/km'kmdb = create_engine( initation, pool_recycle=3600 ) # connect to serverkmdb.echo = FalseConn = kmdb.connect()Meta = MetaData(bind=kmdb)My_Session = sessionmaker()My_Session.configure( bind=kmdb )MySession=My_Session()表說明:country_hdl = Table( 'km_test_mapping', Meta, Column( 'country_mapping_id', Integer, primary_key=True ), Column( 'origin_client_id', String( 40 ) ), Column( 'origin_source_id', String( 30 ) ), Column( 'origin_cntrp_country', String( 30 ) ), Column( 'som_cntrp_country', String( 30 ) ), Column( 'can_use', Boolean ), UniqueConstraint( 'origin_client_id', 'origin_source_id', 'origin_cntrp_country' ) )# 映射表到類國家class Country( object ): passmapper( Country, country_hdl )cntry = Country()#要傳遞的動態變量(要更改的過濾器和值):#I want to dynamically search for origin_client_id = MX01 and if found replace origin_client_id with CAL01. These values are passed as variables by user myfilter = {'origin_source_id': 'MX01’} updatefieldvalue={'origin_client_id':'CAL01’} #查詢函數:query = MySession.query( country_hdl ).filter_by( **myfilter ) results = query.all()#如果找到則替換字段:if results: for column,value in updatefieldvalue.items(): setattr(results[0],column,value) 錯誤 :Traceback (most recent call last):File "/Users/gerardrafie/Developments/KPIMinds/sampleapp/db.py", line 63, in <module> . setattr(results[0],column,value) . AttributeError: can't set attribute .
通過 SQLAlchemy 動態搜索和修改表中的值
慕婉清6462132
2021-06-04 14:45:53