Calculate Sum and Insert as Row - sql-server

Question

Using SSIS I am bringing in raw text files that contain this in the output:
I use this data later to report on. The Key columns get pivoted. However, I don't want to show all those columns individually, I only want to show the total.
To accomplish this my idea was calculate the Sum on insert using a trigger, and then insert the sum as a new row into the data.
The output would look something like:
Is what I'm trying to do possible? Is there a better way to do this dynamically on pivot? To be clear I'm not just pivoting these rows for a report, there are other ones that don't need the sum calculated.

Answer 1

Using derived column and Script Component
You can achieve this by following these steps:
Add a derived column (name: intValue) with the following expression:
(DT_I4)(RIGHT([Value],2) == "GB" ? SUBSTRING([Value],1,FINDSTRING( [Value], " ", 1)) : "0")
So if the value ends with GB then the number is taken else the result is 0.
After that add a script component, in the Input and Output Properties, click on the Output and set the SynchronousInput property to None
Add 2 Output Columns outKey , outValue
In the Script Editor write the following script (VB.NET)
Private SumValues As Integer = 0
Public Overrides Sub PostExecute()
MyBase.PostExecute()
Output0Buffer.AddRow()
Output0Buffer.outKey = ""
Output0Buffer.outValue = SumValues.ToString & " GB"
End Sub
Public Overrides Sub Input0_ProcessInputRow(ByVal Row As Input0Buffer)
Output0Buffer.AddRow()
Output0Buffer.outKey = Row.Key
Output0Buffer.outValue = Row.Value
SumValues += Row.intValue
End Sub

Answer 2

I am going to show you a way but I don't recommend adding total to the end of the detail data. If you are going to report on it show it as a total.
After source add a data transformation:
C#
Add two columns to your data flow: Size int and type string
Select Value as readonly
Here is the code:
string[] splits = Row.value.ToString().Split(' '); //Make sure single quote for char
int goodValue;
if(Int32.TryParse(splits[0], out goodValue))
{
Row.Size = goodValue;
Row.Type = "GB";
}
else
{
Row.Size = 0;
Row.Type="None";
}
Now you have the data with the proper data types to do arithmatic in your table.
If you really want the data in your format. Add a multicast and an aggregate and SUM(Size) and then merge back into your original flow.

Answer 3

I was able to solve my problem in another way using a trigger.
I used this code:
INSERT INTO [Table] (
[Filename]
, [Type]
, [DeviceSN]
, [Property]
, [Value]
)
SELECT ms.[Filename],
ms.[Type],
ms.[DeviceSN],
'Memory Device.Total' AS [Key],
CAST(SUM(CAST(left(ms.[Value], 2) as INT)) AS VARCHAR) + ' GB' as 'Value'
FROM [Table] ms
JOIN inserted i ON i.Row# = ms.Row#
WHERE ms.[Value] like '%GB'
GROUP BY ms.[filename],
ms.[type],
ms.[devicesn]