MySQL: Returning multiple columns from an in-line subquery - sql

Question

I'm creating an SQL statement that will return a month by month summary on sales.
The summary will list some simple columns for the date, total number of sales and the total value of sales.
However, in addition to these columns, i'd like to include 3 more that will list the months best customer by amount spent. For these columns, I need some kind of inline subquery that can return their ID, Name and the Amount they spent.
My current effort uses an inline SELECT statement, however, from my knowledge on how to implement these, you can only return one column and row per in-line statement.
To get around this with my scenario, I can of course create 3 separate in-line statements, however, besides this seeming impractical, it increases the query time more that necessary.
SELECT
DATE_FORMAT(OrderDate,'%M %Y') AS OrderMonth,
COUNT(OrderID) AS TotalOrders,
SUM(OrderTotal) AS TotalAmount,
(SELECT SUM(OrderTotal) FROM Orders WHERE DATE_FORMAT(OrderDate,'%M %Y') = OrderMonth GROUP BY OrderCustomerFK ORDER BY SUM(OrderTotal) DESC LIMIT 1) AS TotalCustomerAmount,
(SELECT OrderCustomerFK FROM Orders WHERE DATE_FORMAT(OrderDate,'%M %Y') = OrderMonth GROUP BY OrderCustomerFK ORDER BY SUM(OrderTotal) DESC LIMIT 1) AS CustomerID,
(SELECT CustomerName FROM Orders INNER JOIN Customers ON OrderCustomerFK = CustomerID WHERE DATE_FORMAT(OrderDate,'%M %Y') = OrderMonth GROUP BY OrderCustomerFK ORDER BY SUM(OrderTotal) DESC LIMIT 1) AS CustomerName
FROM Orders
GROUP BY DATE_FORMAT(OrderDate,'%m%y')
ORDER BY DATE_FORMAT(OrderDate,'%y%m') DESC
How can i better structure this query?
FULL ANSWER
After some tweaking of Dave Barkers solution, I have a final version for anyone in the future looking for help.
The solution by Dave Barker worked perfectly with the customer details, however, it made the simpler Total Sales and Total Sale Amount columns get some crazy figures.
SELECT
Y.OrderMonth, Y.TotalOrders, Y.TotalAmount,
Z.OrdCustFK, Z.CustCompany, Z.CustOrdTotal, Z.CustSalesTotal
FROM
(SELECT
OrdDate,
DATE_FORMAT(OrdDate,'%M %Y') AS OrderMonth,
COUNT(OrderID) AS TotalOrders,
SUM(OrdGrandTotal) AS TotalAmount
FROM Orders
WHERE OrdConfirmed = 1
GROUP BY DATE_FORMAT(OrdDate,'%m%y')
ORDER BY DATE_FORMAT(OrdDate,'%Y%m') DESC)
Y INNER JOIN
(SELECT
DATE_FORMAT(OrdDate,'%M %Y') AS CustMonth,
OrdCustFK,
CustCompany,
COUNT(OrderID) AS CustOrdTotal,
SUM(OrdGrandTotal) AS CustSalesTotal
FROM Orders INNER JOIN CustomerDetails ON OrdCustFK = CustomerID
WHERE OrdConfirmed = 1
GROUP BY DATE_FORMAT(OrdDate,'%m%y'), OrdCustFK
ORDER BY SUM(OrdGrandTotal) DESC)
Z ON Z.CustMonth = Y.OrderMonth
GROUP BY DATE_FORMAT(OrdDate,'%Y%m')
ORDER BY DATE_FORMAT(OrdDate,'%Y%m') DESC

Answer 1

Move the inline SQL to be a inner join query. So you'd have something like...
SELECT DATE_FORMAT(OrderDate,'%M %Y') AS OrderMonth, COUNT(OrderID) AS TotalOrders, SUM(OrderTotal) AS TotalAmount, Z.OrderCustomerFK, Z.CustomerName, z.OrderTotal as CustomerTotal
FROM Orders
INNER JOIN (SELECT DATE_FORMAT(OrderDate,'%M %Y') as Mon, OrderCustomerFK, CustomerName, SUM(OrderTotal) as OrderTotal
FROM Orders
GROUP BY DATE_FORMAT(OrderDate,'%M %Y'), OrderCustomerFK, CustomerName ORDER BY SUM(OrderTotal) DESC LIMIT 1) Z
ON Z.Mon = DATE_FORMAT(OrderDate,'%M %Y')
GROUP BY DATE_FORMAT(OrderDate,'%m%y'), Z.OrderCustomerFK, Z.CustomerName
ORDER BY DATE_FORMAT(OrderDate,'%y%m') DESC

Answer 2

You can also do something like:
SELECT
a.`y`,
( SELECT #c:=NULL ) AS `temp`,
( SELECT #d:=NULL ) AS `temp`,
( SELECT
CONCAT(#c:=b.`c`, #d:=b.`d`)
FROM `b`
ORDER BY b.`uid`
LIMIT 1 ) AS `temp`,
#c as c,
#d as d
FROM `a`

Answer 3

Give this a shot:
SELECT CONCAT(o.order_month, ' ', o.order_year),
o.total_orders,
o.total_amount,
x.sum_order_total,
x.ordercustomerfk,
x.customername
FROM (SELECT MONTH(t.orderdate) AS order_month,
YEAR(t.orderdate) AS order_year
COUNT(t.orderid) AS total_orders,
SUM(t.ordertotal) AS total_amount
FROM ORDERS t
GROUP BY MONTH(t.orderdate), YEAR(t.orderdate)) o
JOIN (SELECT MONTH(t.orderdate) AS ordermonth,
YEAR(t.orderdate) AS orderyear
SUM(t.ordertotal) 'sum_order_total',
t.ordercustomerfk,
c.customername
FROM ORDERS t
JOIN CUSTOMERS c ON c.customerid = o.ordercustomerfk
GROUP BY t.ordercustomerfk, MONTH(t.orderdate), YEAR(t.orderdate)) x ON x.order_month = o.order_month
AND x.order_year = o.order_year
ORDER BY o.order_year DESC, o.order_month DESC