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Start your free trialErin DeSpain
6,763 PointsImpossible Results? "The subquery didn't return all CustomerIDs for people who identify as female (F)."
Question Content:
In a car database there is a Sale table with columns, SaleID, CarID, CustomerID, LocationID, SalesRepID, SaleAmount and SaleDate and a Customer table with columns, CustomerID, FirstName, LastName, Gender and SSN.
Use a subquery as a derived table to show all sales to female ('F') customers. Select all columns from the Sale table only.
My Code:
SELECT * FROM Sale AS s
INNER JOIN (
SELECT Gender FROM Customer WHERE Gender = 'F') AS c
ON c.CustomerID = s.CustomerID
Response:
Bummer: The subquery didn't return all CustomerIDs for people who identify as female (F).
Question:
Where did things go wrong? NOTE: I've also tried entering the Sale
Fields individually to prevent the normal duplication of fields one gets with a join. Consequence: same exact result.
1 Answer
KRIS NIKOLAISEN
54,971 PointsSince you are joining CustomerID you will want to select CustomerID instead of Gender in your subquery.
SELECT * FROM Sale AS s
INNER JOIN (
SELECT CustomerID FROM Customer WHERE Gender = 'F') AS c
ON c.CustomerID = s.CustomerID
Erin DeSpain
6,763 PointsErin DeSpain
6,763 PointsThank you! That was perfect!