SQL Server 2017

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CREATE TABLE [dbo].[Time](
    [GUIDEmployee] int NULL,
    [Date] [datetime] NOT NULL,
    [Hours] [decimal](18, 2) NOT NULL);

INSERT INTO [dbo].[Time]
VALUES

(  1  ,  '2012-03-02',          2.00),
(  1  ,  '2012-03-02',          4.50),
(  1  ,  '2012-03-19',          1.50),
(  1  ,  '2012-03-19',          1.50),
(  1  ,  '2012-03-12',          2.00),
(  1  ,  '2012-03-16',          4.50);
6 rows affected

SELECT [GuidEmployee],
	   [Date],
	   [Hours], 
	   SUM([Hours]) OVER(PARTITION BY GuidEmployee,[Date]) as total_hours
FROM [dbo].[Time];


GuidEmployee
Date
Hours
total_hours


1
02/03/2012 00:00:00
2.00
6.50

1
02/03/2012 00:00:00
4.50
6.50

1
12/03/2012 00:00:00
2.00
2.00

1
16/03/2012 00:00:00
4.50
4.50

1
19/03/2012 00:00:00
1.50
3.00

1
19/03/2012 00:00:00
1.50
3.00


SELECT [GuidEmployee],
	   [Date], 
	   SUM([Hours]) 
FROM [dbo].[Time]
GROUP BY [GuidEmployee],[Date];


GuidEmployee
Date
(No column name)


1
02/03/2012 00:00:00
6.50

1
12/03/2012 00:00:00
2.00

1
16/03/2012 00:00:00
4.50

1
19/03/2012 00:00:00
3.00

GuidEmployee	Date	Hours	total_hours
1	02/03/2012 00:00:00	2.00	6.50
1	02/03/2012 00:00:00	4.50	6.50
1	12/03/2012 00:00:00	2.00	2.00
1	16/03/2012 00:00:00	4.50	4.50
1	19/03/2012 00:00:00	1.50	3.00
1	19/03/2012 00:00:00	1.50	3.00