SQL Server 触发器 当插入表数据时，修改表数据其他字段值

ALTER TRIGGER [dbo].[ICStockBill_daying2]
   on [dbo].[ICStockBill] 
  after insert --更新触发
  as
 
BEGIN
    SET NOCOUNT ON;
    DECLARE @a VARCHAR (20)  --定义变量
    SET @a = (SELECT
	FInterID
    FROM
        inserted 
) --变量赋值 ，找到对应更新的那一行。
update  ICStockBillEntry 
set FEntrySelfB0857 = (select top 1 b.FQty from ICInventory b where ICStockBillEntry.FItemID = b.FItemID and  ICStockBillEntry.FDCStockID=b.FStockID)
where  finterid =@a
end