I want to calculate the Sum of the Field which has Time DataType.
My Table is Below:
TableA:
TotalTime
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You could sum the total number of seconds, or datediff(second,0,datecolumn). You can format that as a time string with some math. For example, the total number of minutes is totalseconds / 60 % 60. For example:
select cast(sum(datediff(second,0,dt))/3600 as varchar(12)) + ':' +
right('0' + cast(sum(datediff(second,0,dt))/60%60 as varchar(2)),2) +
':' + right('0' + cast(sum(datediff(second,0,dt))%60 as varchar(2)),2)
from TestTable
Working code at SQL Fiddle.