SQL Server 2014

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CREATE TABLE Requests
(RequestID int,
Value1Old int,
Value1New int,
Value2Old int,
Value2New int);

INSERT INTO Requests
(RequestID, Value1Old, Value1New, Value2Old, Value2New)
VALUES
(1, NULL, 50, NULL, NULL),
(2, 50, 100, NULL, 100),
(3, 100, 200, 100, 300),
(4, NULL, NULL, 300, 500),
(5, 200, 0, 600, 1000),
(6, NULL, NULL, 1000, 0);
6 rows affected

create function fnChange (@Old int, @New int) 
returns varchar(10) as
begin
	return (
	select 
		case
			when IsNull(@Old,0)=IsNull(@New,0) then null
		else
			case when @New=0 or @new is null then 'Delete' else
				case when @Old is null then 'Insert'
				else 'Amend' end
			end
		end 
	)
end
with r as (
	select RequestId, dbo.fnChange(Value1Old,Value1New) Change, Value1Old, Value1New, null Value2Old, null Value2New
	from Requests
	union all
	select RequestId, dbo.fnChange(Value2Old,Value2New) Change, null Value1Old, null Value1New, Value2Old, Value2New
	from Requests
)
select requestId, Change, 
	Max(Value1Old) Value1Old, Max(Value1New) value1New,
	Max(Value2Old) Value2Old, Max(Value2New) value2New
from r where change is not null
group by requestId, Change
order by requestId


requestId
Change
Value1Old
value1New
Value2Old
value2New


1
Insert
null
50
null
null

2
Amend
50
100
null
null

2
Insert
null
null
null
100

3
Amend
100
200
100
300

4
Amend
null
null
300
500

5
Amend
null
null
600
1000

5
Delete
200
0
null
null

6
Delete
null
null
1000
0


Warning: Null value is eliminated by an aggregate or other SET operation.

requestId	Change	Value1Old	value1New	Value2Old	value2New
1	Insert	null	50	null	null
2	Amend	50	100	null	null
2	Insert	null	null	null	100
3	Amend	100	200	100	300
4	Amend	null	null	300	500
5	Amend	null	null	600	1000
5	Delete	200	0	null	null
6	Delete	null	null	1000	0