刚个帖子没写明白:
现在有订单表,订单子表,出库表,出库子表,其中订单有(contract_id),订单子表有(ddety_id,fen_id,contract_id) 出库表有(ckbill_id,contract_id) 出库子表有(finter_id,ckbill_id,),各个表之间的关系是:
订单子表通过contract_id对应 订单表 ,出库表通过 contract_id 对应订单表,出库子表通过ckbill_id对应出库表,还有个TK(A,B,C)表 其中A=finter_id,B=ckbill_id,c=订单子表的主键, ps:订单子表是ddety_id,fen_id 的联合主键,想在TK表中把这2个主键合并成一个字段放到TK.C中, 请教大虾们应该怎么写........