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select name, cast(time as time) as hours
into t
from (values ('A', '5:30'),
('B', '3:30'),
('A', '4:00'),
('C', '2:00'),
('B', '4:55')
) v(name, time)
5 rows affected
select name, sum(datediff(minute, 0, hours)) / 60.0
from t
group by name
| name | (No column name) |
|---|---|
| A | 9.500000 |
| B | 8.416666 |
| C | 2.000000 |
select name, dateadd(minute, sum(datediff(minute, 0, hours)), convert(time, '00:00:00'))
from t
group by name
| name | (No column name) |
|---|---|
| A | 09:30:00 |
| B | 08:25:00 |
| C | 02:00:00 |