sql server - Replacing the values in sql table -

orderid, ordertime, orderitem  1,       1 am,      orange 1,       2 am,      apple 2,       3 am,      grape 3,       2 am,      apple 3,       3 am,      coconut 1,       5 am,      banana 1,       6 am,      apple 

the above original table. below table want. if order id same continuously, wwant change order time minimum time.

orderid, ordertime, orderitem  1,       1 am,      orange 1,       1 am,      apple 2,       3 am,      grape 3,       2 am,      apple 3,       2 am,      coconut 1,       5 am,      banana 1,       5 am,      apple 

there no "natural" order data in sql server if don't specify order order in no way guaranteed. need column can use define order by. once have can like

declare @data table  ( orderitemid int identity(1,1) primary key, orderid int,  ordertime datetime,  orderitem varchar(10))  insert @data select 1,'00:01:00','orange' union select 1,'00:01:00','apple' union select 2,'00:03:00','grape' union select 3,'00:02:00','apple' union select 3,'00:02:00','coconut' union select 1,'00:05:00','banana' union select 1,'00:05:00','apple';  cte1 ( select *, row_number() on (order orderitemid)- row_number() on (partition orderid order orderitemid) grp @data ), cte2 ( select *, min(ordertime) on (partition orderid, grp) minordertime cte1 ) update cte2 set ordertime = minordertime  select orderid,convert(varchar, ordertime, 8) orderitemid, orderitem  @data  order orderitemid