Det här är ganska fult, men jag tror att det gör vad du behöver det för?
Declare @YourTable table ([Event] varchar(100),[Start] DateTime,[End] DateTime, [Tag] varchar(25))
Insert Into @YourTable values
('10PIC700422.PV 10-PSV-700073A 10-PSV-700073B','9/9/16 10:44','9/9/16 10:48','Big'),
('10PIC700422.PV 10-PSV-700073A 10-PSV-700073B','9/9/16 10:44','9/9/16 10:49','Big'),
('10PIC700422.PV 10-PSV-700073A 10-PSV-700073B','9/9/16 10:50','9/9/16 10:51','Small'),
('11PIC41010.PV 11-PSV-401002A 11-PSV-401002B','4/4/16 12:51','4/4/16 13:58','Big'),
('11PIC41010.PV 11-PSV-401002A 11-PSV-401002B','4/4/16 14:04','4/4/16 14:29','Small'),
('11PIC41010.PV 11-PSV-401002A 11-PSV-401002B','4/4/16 14:51','4/4/16 14:58','Big'),
('11PIC41010.PV 11-PSV-401002A 11-PSV-401002B','4/4/16 15:04','4/4/16 15:29','Small'),
('11PIC41010.PV 11-PSV-401002A 11-PSV-401002B','4-4-16 15:45','4-4-16 15:55','Big'),
('11PIC41010.PV 11-PSV-401002W 11-PSV-401002D','4/4/16 16:04','4/4/16 16:45','Big');
Select [Event]
,[Start]
,[End]
,[Tag]
,[Tag_new] = case when Tag = 'Big'
and Lead(Tag,1,'') over (Partition By Event
Order By Start
)
= 'Small'
then 'Small'
else tag
end
,[Tag_new2] = case when (Tag = 'Big'
and lag(Tag,1,'') over (Partition By Event
Order By Start
)
= 'Small'
and Lead(Tag,1,'') over (Partition By Event
Order By Start
)
= 'Small'
)
or (Tag = 'Small'
and lag(Tag,2,'') over (Partition By Event
Order By Start
)
= 'Small'
and lag(Tag,1,'') over (Partition By Event
Order By Start
)
= 'Big'
)
then 'Small2'
else case when Tag = 'Big'
and Lead(Tag,1,'') over (Partition By Event
Order By Start
)
= 'Small'
then 'Small'
else tag
end
end
From @YourTable;
Som svar på din uppdatering, och förutsatt att du kan lägga till några kolumner i din Staging-tabell:
Declare @YourTable table (EventRN int, StartRN int, MaxStartRN int, [Event] varchar(100),[Start] DateTime,[End] DateTime, [Tag] varchar(25), [TagNext] varchar(25))
Insert Into @YourTable values
(null,null,null,'10PIC700422.PV 10-PSV-700073A 10-PSV-700073B','9/9/16 10:44','9/9/16 10:49','Big',null),
(null,null,null,'10PIC700422.PV 10-PSV-700073A 10-PSV-700073B','9/9/16 10:50','9/9/16 10:51','Small',null),
(null,null,null,'11PIC41010.PV 11-PSV-401002A 11-PSV-401002B','4/4/16 12:51','4/4/16 13:58','Big',null),
(null,null,null,'11PIC41010.PV 11-PSV-401002A 11-PSV-401002B','4/4/16 14:04','4/4/16 14:29','Small',null),
(null,null,null,'11PIC41010.PV 11-PSV-401002A 11-PSV-401002B','4/4/16 14:51','4/4/16 14:58','Big',null),
(null,null,null,'11PIC41010.PV 11-PSV-401002A 11-PSV-401002B','4/4/16 15:04','4/4/16 15:29','Small',null),
(null,null,null,'11PIC41010.PV 11-PSV-401002A 11-PSV-401002B','4/4/16 15:30','4/4/16 15:32','Small',null),
(null,null,null,'11PIC41010.PV 11-PSV-401002A 11-PSV-401002B','4-4-16 15:45','4-4-16 15:55','Big',null),
(null,null,null,'11PIC41010.PV 11-PSV-401002W 11-PSV-401002D','4/4/16 16:04','4/4/16 16:45','Big',null);
update t
set EventRN = tt.EventRN
,StartRN = tt.StartRN
,MaxStartRN = tt.MaxStartRN
,TagNext = tt.TagNext
from @YourTable t
inner join (
select dense_rank() over (order by Event
) as EventRN
,row_number() over (partition by Event
order by Start
) as StartRN
,count(1) over (partition by Event) as MaxStartRN
,[Event]
,[Start]
,[End]
,[Tag]
,lead(Tag,1,null) over (partition by Event
order by Start
)
as TagNext
from @YourTable
) tt
on(t.[Event] = tt.[Event]
and t.[Start] = tt.[Start]
and t.[End] = tt.[End]
and t.Tag = tt.Tag
);
with cte as
(
select EventRN
,StartRN
,MaxStartRN
,[Event]
,[Start]
,[End]
,Tag
,TagNext
,cast(null as varchar(25)) as TagPrev
,case when TagNext = 'Small'
then TagNext
else Tag
end as TagNew
from @YourTable
where EventRN = 1
and StartRN = 1
union all
select t.EventRN
,t.StartRN
,t.MaxStartRN
,t.[Event]
,t.[Start]
,t.[End]
,t.Tag
,t.TagNext
,case when t.EventRN = c.EventRN then c.Tag else null end as TagPrev
,case when t.EventRN = c.EventRN and c.Tag = 'Small' and t.Tag = 'Big' and t.TagNext = 'Small'
or t.EventRN = c.EventRN and c.TagNew = 'Small2' and t.Tag = 'Small'
then 'Small2'
else case when t.TagNext = 'Small'
then t.TagNext
else t.Tag
end
end
from cte c
inner join @YourTable t
on((c.StartRN < c.MaxStartRN
and t.EventRN = c.EventRN
and t.StartRN = c.StartRN+1
)
or (c.StartRN = c.MaxStartRN
and t.EventRN = c.EventRN+1
and t.StartRN = 1
)
)
)
select [Event]
,[Start]
,[End]
,Tag
,TagNew
from cte
order by Event
,Start;