Ali

SQLSERVER笔记alter table table_name add primary key(字段1，字段2) 添加联合主键SELECT dbo.PO.FNUMBER AS 订单编号, dbo.Supply.FSupplyName AS 供应商名称, dbo.Supply.FSupplyTel AS 联系电话, dbo.PO.FDATE AS 订货日期, dbo.Materiel.FMName AS 物料名称, dbo.Materiel.FSpec AS 物料规格, dbo.U