SQL Server : Arithmetic overflow error converting expression to data type int

Question

I'm getting this error

msg 8115, level 16, state 2, line 18
Arithmetic overflow error converting expression to data type int.

with this SQL query

DECLARE @year VARCHAR(4);                       
DECLARE @month VARCHAR(2);                      

-- START OF CONFIGURATION SECTION                       
-- THIS IS THE ONLY SECTION THAT SHOULD BE MODIFIED                     
-- SET THE YEAR AND MONTH PARAMETERS                        

SET @year = '2013';                     
SET @month = '3';  -- 1 = January.... 12 = Decemeber.                       

-- END OF CONFIGURATION SECTION                     

DECLARE @startDate DATE                     
DECLARE @endDate DATE                       
SET @startDate = @year + '-' + @month + '-01 00:00:00';                     
SET @endDate = DATEADD(MONTH, 1, @startDate);                       

SELECT                          
    DATEPART(YEAR, dateTimeStamp) AS [Year]                         
    , DATEPART(MONTH, dateTimeStamp) AS [Month]                         
    , COUNT(*) AS NumStreams                        
    , [platform] AS [Platform]                      
    , deliverableName AS [Deliverable Name]                     
    , SUM(billableDuration) AS NumSecondsDelivered                      
FROM                            
    DeliveryTransactions                        
WHERE                           
    dateTimeStamp >= @startDate                     
AND dateTimeStamp < @endDate                        
GROUP BY                            
    DATEPART(YEAR, dateTimeStamp)                       
    , DATEPART(MONTH, dateTimeStamp)                        
    , [platform]                        
    , deliverableName                       
ORDER BY                            
    [platform]                      
    , DATEPART(YEAR, dateTimeStamp)                         
    , DATEPART(MONTH, dateTimeStamp)                        
    , deliverableName   

Answer 1

Is the problem with SUM(billableDuration)? To find out, try commenting out that line and see if it works.

It could be that the sum is exceeding the maximum int. If so, try replacing it with SUM(CAST(billableDuration AS BIGINT)).

Answer 2

Very simple:

Use COUNT_BIG(*) AS NumStreams

Answer 3

Change SUM(billableDuration) AS NumSecondsDelivered to

sum(cast(billableDuration as bigint)) or

sum(cast(billableDuration as numeric(12, 0))) according to your need.

The resultant type of of Sum expression is the same as the data type used. It throws error at time of overflow. So casting the column to larger capacity data type and then using Sum operation works fine.