Query for computing a column using other computed columns - sql

Question

Table: Project Details
+-----+------------------+------------+--------------+------------+
| GPN | EmployeePosition | Project.No | ChargedHours | PayPerHour |
+-----+------------------+------------+--------------+------------+
| 2 | B | 101 | 50 | 57 |
| 3 | C | 100 | 75 | 44 |
| 4 | D | 100 | 100 | 24.75 |
| 5 | E | 103 | 125 | 19.25 |
| 6 | F | 101 | 150 | 16 |
| 7 | C | 100 | 175 | 44 |
+-----+------------------+------------+--------------+------------+
I need to find out total pay of each Project. So first I have to find out Total pay per employee and group it by Project.No.
The table below shows the Total pay per Employee which is created using other 2 existing columns
+-----+-------------+---------+------------+----------+----------------+
| GPN | EmpPosition | Proj.No | ChargedHrs | PayPerHr | TotalPayPerEmp |
+-----+-------------+---------+------------+----------+----------------+
| 2 | B | 101 | 50 | 57 | 993.75 |
| 3 | C | 100 | 75 | 44 | 2850 |
| 4 | D | 100 | 100 | 24.75 | 3300 |
| 5 | E | 103 | 125 | 19.25 | 2406.25 |
| 6 | F | 101 | 150 | 16 | 2400 |
| 7 | C | 100 | 175 | 44 | 7700 |
+-----+-------------+---------+------------+----------+----------------+
My Query:
Select EngNumber, SUM([CharHrs])[SumOfChargedHours], Levell, CostPH,
SUM([CharHrs])*CostPH [TotalPayPerEmployee]
FROM data1.dbo.PayedPerHour
GROUP BY EngNumber, Levell, TotalPayPerEmployee, CostPH
ORDER BY EngNumber;
Update data1.dbo.PayedPerHour
SET CostPH = CASE Levell
WHEN 'Associate Director' THEN '79.75'
WHEN 'Senior Manager' THEN '57'
WHEN 'Manager' THEN '44'
WHEN 'Senior' THEN '24.75'
WHEN 'Staff 2, 3 & 4' THEN '19.25'
WHEN 'Staff 1' THEN '16'
ELSE 'NULL'
END
WHERE Levell IN('Associate Director', 'Senior Manager','Manager', 'Senior',
'Staff 2, 3 & 4', 'Staff 1');
I want to group the TotalPayPerEmp by Proj.No but i cant accomplish it.
I would have made silly mistakes in the query since I'm very new to sql so please regret them
Expected table:
+---------+--------------------+
| Proj.No | TotalPayPerProject |
+---------+--------------------+
| 100 | 14093.75 |
| 101 | 5250 |
| 103 | 4881.25 |
+---------+--------------------+

Answer 1

I think this could be done using some of your algorithm, except at the ProjectNo granularity:
SELECT ProjectNo
,SUM(ChargedHours*PayPerHour) [TotalPayPerProject]
FROM ProjectDetails
GROUP BY ProjectNo
This gives output:
ProjectNo TotalPayPerProject
100 13475
101 5250
103 2406.25
This is different from your expected output, for some reason.
Here's a SQL fiddle: http://sqlfiddle.com/#!6/21a33/2/0