Transposing Table Data From Rows to Columns Into a View

Question

I have a web-based HRMS (Human Resources Management System) ERP with a back-end SQL Server 2008 R2. I'm trying to compare the actual manpower with the manpower contract requirements for 30 cost centers. My base data is as follows:
TABLE Contract_Requirements: Class, Cost_Center, Contract_Qty
VIEW Manpower_Count: Class, Cost_Center, Head_Count
I would like to transpose the rows to columns of both objects so that the end result would be similar to the following:
          Class          |          Site_1          |         
Site_2          |          Site_3          |          Site_4         
|...
Superintendent                   1                              
1                             1                            
1
Supervisor                           2                              
2                             2                            
2
Medic                                   1                              
2                             1                            
3
Crane Operator                   1                              
1                             2                            
1
The target layout is that each individual record displays the number of employees of a specific class allocated to each individual cost center; the cost centers become columns. I was able to accomplish this using the following TSQL:
DECLARE @cols AS NVARCHAR(MAX), @query AS NVARCHAR(MAX)
SELECT @cols = STUFF((SELECT ',' + QUOTENAME(Cost_Center)
FROM Manpower_Count
GROUP BY Cost_Center
ORDER BY Cost_Center
FOR XML PATH(''), TYPE
).value('.', 'NVARCHAR(MAX)'),1,1,'')
SET @query = 'SELECT Class,' + @cols + ' INTO
Manpower_Allocation_Matrix FROM
(SELECT Class, Cost_Center, Head_Count
FROM Manpower_Count) x
PIVOT (SUM(Head_Count) FOR Cost_Center IN (' + @cols + '))p'
EXECUTE(@query);
The only problem is if an employee is transferred from one cost center to another, which happens a lot on a daily basis, this would only be reflected in the base view; the resultant table will not be updated. I would have to repeatedly drop and recreate
the table which isn't efficient, nor is it the right practice. I was thinking of automating this using a scheduled procedure every day, but it's still not going to work. The actual manpower count must be known at real-time, meaning any changes should be reflected
immediately after any employee transfer. What is the most efficient way to automate this process and store real-time data? FYI, I'm not an SQL expert and have never worked with
stored procedures or triggers. I would also like to point out the number of cost centers is never fixed; consequently the number of columns aren't fixed either.

Answer 1

Hi Seif,
You can pivot straightly on the base view to get real time data. The dynamic PIVOT is encapsuled in a Stored Procedure(SP), so every time your want to check the manpower count you can call the SP.
--This table is the same with your base view
CREATE TABLE srcTbl(
Employee_Code VARCHAR(99),
Employee_Name VARCHAR(99),
Cost_Center_name VARCHAR(99),
Cost_Center_NO VARCHAR(99),
Position_ VARCHAR(99),
Total_Salary Money
INSERT INTO srcTbl VALUES('CAN-010','John Doe A','Site 120',120,'Fork Lift Operator',150);
INSERT INTO srcTbl VALUES('EGY-130','John Doe B','Site 150',150,'Driver',200);
INSERT INTO srcTbl VALUES('IND-120','John Doe C','Site 113',113,'Fork Lift Operator',150);
INSERT INTO srcTbl VALUES('SAU-50','John Doe D','Site 112',112,'Mechanic',261.948);
INSERT INTO srcTbl VALUES('PHI-90','John Doe F','Site 112',112,'Crane Operator',250);
INSERT INTO srcTbl VALUES('CAN-012','John Doe G','Site 120',120,'Driver',200);
INSERT INTO srcTbl VALUES('IND-129','John Doe I','Site 150',150,'Superintendent',2300);
INSERT INTO srcTbl VALUES('PAK-464','John Doe X','Site 141',141,'Supervisor',1800);
INSERT INTO srcTbl VALUES('FRA-003','John Doe M','Site 120',120,'Medic',700);
GO
CREATE PROC proc1
AS
DECLARE @cols AS NVARCHAR(MAX), @query AS NVARCHAR(MAX)
SELECT @cols = STUFF((SELECT ',' + QUOTENAME(Cost_Center_no)
FROM srcTbl
GROUP BY Cost_Center_no
ORDER BY Cost_Center_no
FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'),1,1,'')
SET @query=N';WITH Cte AS(
SELECT Position_ as Class,Cost_Center_No, COUNT(1) AS Head_Count FROM srcTbl
GROUP BY Position_,Cost_Center_No
SELECT Class,'+@cols+'
FROM Cte
PIVOT
(MAX(Head_Count) FOR Cost_Center_No IN('+@cols+')) AS PvtTbl
ORDER BY Class';
EXEC sp_executesql @query ;
GO
EXEC PROC1
DROP PROC PROC1
DROP TABLE srcTbl
If you have any question, feel free to let me know.
Eric Zhang
TechNet Community Support