Dynamically sum table columns in SQL Server - sql

Question

I have the following data in a table with columns Col1,Col2,Col3,Col4, Col5......... Col153
The sample data in the first four columns in the table:
CREATE TABLE dbo.MyTable (LocaID VARCHAR(10),Col1 INT, Col2 INT,Col3 INT,Col4 INT)
INSERT INTO dbo.MyTable values
('LV',2,6,4,7),('CH',4,8,3,1),('LV',1,3,9,3),('MC',7,0,5,4),
('LV',4,5,2,4),('MC',7,1,4,9),('MC',5,1,8,1),('CH',7,3,4,0),
('MC',2,5,7,3);
There are 153 columns that I need to sum individually. I used the query below to get the list of columns:
-- This is to get the columns names
SELECT
COLUMN_NAME AS Col_Names
INTO #Column
From INFORMATION_SCHEMA.COLUMNS
Where TABLE_NAME Like 'MyTable'
I tried to use the query below to dynamically sum them:
DECLARE #cols AS NVARCHAR(MAX),
#query AS NVARCHAR(MAX);
SET #cols = STUFF((SELECT distinct ',' + QUOTENAME(Col_Names)
FROM #Column
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)')
,1,1,'')
SET #query= 'SELECT
SUM('+#cols+')
FROM dbo.MyTable GROUP BY [LocaID]'
PRINT #query
When I print the result to check if the query is correct I got this:
SELECT SUM([Col1],[Col2],[Col3],[Col4],[LocaID])
FROM dbo.MyTable GROUP BY [LocaID]
Which is clearly not correct. What I need is:
SELECT
[LocaID],
SUM([Col1]) AS [Col1],
SUM([Col2]) AS [Col2],
SUM([Col3]) AS [Col3],
SUM([Col4]) AS [Col4]
FROM dbo.MyTable
GROUP BY [LocaID]
For all the 153 columns. There is only one LocaID in the table.

Answer 1

If you want to SUM individual column, you need to change your STUFF function. You need to apply SUM function for all the columns, like below.
DECLARE #cols AS NVARCHAR(MAX),
#query AS NVARCHAR(MAX);
SET #cols = STUFF((SELECT distinct ',SUM(' + QUOTENAME(Col_Names) + ')'
FROM #Column
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)') ,1,1,'')
SET #query= 'SELECT [LocaID], '+#cols+'
FROM dbo.MyTable GROUP BY [LocaID]'
PRINT #query

Answer 2

Thanks you so much #Vad Soft, I adjusted you query to give me what i want
DECLARE #cols AS NVARCHAR(MAX),
#cols2 AS NVARCHAR(MAX),
#query AS NVARCHAR(MAX);
SET #cols = STUFF((
----------------------------------------------------------------------------------
SELECT DISTINCT CONCAT(',SUM(' + QUOTENAME(a.Col_Names) + ') AS ',' ',b.RN)
FROM #Column a
LEFT JOIN
(
SELECT
Col_Names AS RN
from #Column
where Col_Names <> 'LocaID' ) b ON b.RN=a.Col_Names
-------------------------------------------------------------------------------------
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)') ,1,1,'')
SET #cols2 =REVERSE(RIGHT(REVERSE(#cols),LEN(REVERSE(#cols))- CHARINDEX(',',REVERSE(#cols))))
--PRINT #cols2
SET #query= 'SELECT [LocaID],
'+#cols2+'
FROM dbo.MyTable GROUP BY [LocaID]'
--PRINT #cols
EXEC (#query)
---------------------------
DROP TABLE #Column
Output
print #query
SELECT [LocaID],
SUM([Col1]) AS Col1,
SUM([Col2]) AS Col2,
SUM([Col3]) AS Col3,
SUM([Col4]) AS Col4
FROM dbo.MyTable GROUP BY [LocaID]