SQL Spatial Subquery Issue - sql

Question

Greetings Benevolent Gods of Stackoverflow,
I am presently struggling to get a spatially enabled query to work for a SQL assignment I am working on. The wording is as follows:
SELECT PURCHASES.TotalPrice, STORES.GeoLocation, STORES.StoreName
FROM MuffinShop
join (SELECT SUM(PURCHASES.TotalPrice) AS StoreProfit, STORES.StoreName
FROM PURCHASES INNER JOIN STORES ON PURCHASES.StoreID = STORES.StoreID
GROUP BY STORES.StoreName
HAVING (SUM(PURCHASES.TotalPrice) > 600))
What I am trying to do with this query is perform a function query (like avg, sum etc) and get the spatial information back as well. Another example of this would be:
SELECT STORES.StoreName, AVG(REVIEWS.Rating),Stores.Shape
FROM REVIEWS CROSS JOIN
STORES
GROUP BY STORES.StoreName;
This returns a Column 'STORES.Shape' is invalid in the select list because it is not contained in either an aggregate function or the GROUP BY clause. error message.
I know I require a sub query to perform this task, I am just having endless trouble getting it to work. Any help at all would be wildly appreciated.

Answer 1

There are two parts to this question, I would tackle the first problem with the following logic:
List all the store names and their respective geolocations
Get the profit for each store
With that in mind, you need to use the STORES table as your base, then bolt the profit onto it through a sub query or an apply:
SELECT s.StoreName
,s.GeoLocation
,p.StoreProfit
FROM STORES s
INNER JOIN (
SELECT pu.StoreId
,StoreProfit = SUM(pu.TotalPrice)
FROM PURCHASES pu
GROUP BY pu.StoreID
) p
ON p.StoreID = s.StoreID;
This one is a little more efficient:
SELECT s.StoreName
,s.GeoLocation
,profit.StoreProfit
FROM STORES s
CROSS APPLY (
SELECT StoreProfit = SUM(p.TotalPrice)
FROM PURCHASES p
WHERE p.StoreID = s.StoreID
GROUP BY p.StoreID
) profit;
Now for the second part, the error that you are receiving tells you that you need to GROUP BY all columns in your select statement with the exception of your aggregate function(s).
In your second example, you are asking SQL to take an average rating for each store based on an ID, but you are also trying to return another column without including that inside the grouping. I will try to show you what you are asking SQL to do and where the issue lies with the following examples:
-- Data
Id | Rating | Shape
1 | 1 | Triangle
1 | 4 | Triangle
1 | 1 | Square
2 | 1 | Triangle
2 | 5 | Triangle
2 | 3 | Square
SQL Server, please give me the average rating for each store:
SELECT Id, AVG(Rating)
FROM Store
GROUP BY StoreId;
-- Result
Id | Avg(Rating)
1 | 2
2 | 3
SQL Server, please give me the average rating for each store and show its shape in the result (but don't group by it):
SELECT Id, AVG(Rating), Shape
FROM Store
GROUP BY StoreId;
-- Result
Id | Avg(Rating) | Shape
1 | 2 | Do I show Triangle or Square ...... ERROR!!!!
2 | 3 |
It needs to be told to get the average for each store and shape:
SELECT Id, AVG(Rating), Shape
FROM Store
GROUP BY StoreId, Shape;
-- Result
Id | Avg(Rating) | Shape
1 | 2.5 | Triangle
1 | 1 | Square
2 | 3 | Triangle
2 | 3 | Square

Answer 2

As in any spatial query you need an idea of what your final geometry will be. It looks like you are attempting to group by individual stores but delivering an average rating from the subquery. So if I'm reading it right you are just looking to get the stores shape info associated with the average ratings?
Query the stores table for the shape field and join the query you use to get the average rating
select a.shape
b.*
from stores a inner join (your Average rating query with group by here) b
on a.StoreID = b.Storeid