SQL sum aggregate function gives wrong results - sql

Question

My data is given below
Right answer is Sum = 601,050.00
But SQL sum aggregate function gives me wrong answer that is 5078150.00000
15,000.00 27,950.00 24,750.00 11,550.00 7,400.00 7,500.00 14,650.00 12,500.00 32,800.00 35,700.00 94,100.00 10,100.00 19,700.00 22,100.00 35,450.00 28,050.00 50,150.00 69,750.00 13,800.00 3,600.00 18,600.00 2,350.00 7,200.00 21,600.00 7,700.00 4,500.00 2,500.00
select sum(SO_SalesOrder.OrderTotal),l.Name as [Store Name]
From SO_SalesOrder inner join BASE_Location l on
SO_SalesOrder.LocationId = l.LocationId
inner join SO_SalesOrder_Line on SO_SalesOrder.SalesOrderId =
SO_SalesOrder_Line.SalesOrderId
inner join BASE_Product on BASE_Product.ProdId =
SO_SalesOrder_Line.ProdId
inner join BASE_Category on BASE_Category.CategoryId =
BASE_Product.CategoryId
where SO_SalesOrder.OrderDate >= '2018-02-01' and
SO_SalesOrder.OrderDate <= '2018-02-28' and BASE_Category.Name = '1MHNZ'
group by l.Name

Answer 1

There is likely to be a problem with one (or more) of your joins, maybe you have duplicate rows or the joining conditions are not OK.
Remove the group by l.Name, the SUM() aggregate and see if the returned values for SO_SalesOrder.OrderTotal are what you are expecting them to be (you might need to filter with a particular l.Name in a WHERE clause). It's very likely you will see duplicate amounts, or amounts you are not considering when arriving to the value 601,050.00.
If so, try joining the tables 1 by 1 and see which ones are making your rows go comando.

Answer 2

In my opinion your problem depends on the logic of the query.
You have a master-detail relationship between SO_SalesOrder and SO_SalesOrder_line joined by SalesOrderId column.
So if you have three lines in your order you will sum up three times the same OrderTotal.
try with something like this:
select sum(SO_SalesOrder.OrderTotal) Total, l.Name as [Store Name]
From SO_SalesOrder
join BASE_Location l on SO_SalesOrder.LocationId = l.LocationId
where SO_SalesOrder.OrderDate >= '2018-02-01' and SO_SalesOrder.OrderDate <= '28-02-2018'
and exists (
select 0 x
From SO_SalesOrder_Line
join BASE_Product on BASE_Product.ProdId = SO_SalesOrder_Line.ProdId
join BASE_Category on BASE_Category.CategoryId = BASE_Product.CategoryId
where BASE_Category.Name = '1MHNZ'
and SO_SalesOrder_Line.SalesOrderId = SO_SalesOrder.SalesOrderId
)
group by l.Name
P.S.
Check also the dates columns, if they contains also time fraction you should reconsider your upper bound filter.
I suggest you to use and SO_SalesOrder.OrderDate < '01-03-2018' instead of <= 28-02