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Databases

Patrik Horváth
Patrik Horváth
11,110 Points

SQL Select SUBQUERIES

https://teamtreehouse.com/library/querying-relational-databases/subqueries/subqueries

Tank 4 Of 4 : 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 QUERY with Error : Bummer! The subquery didn't return all CustomerIDs for people who identify as female (F).

SELECT * FROM Sale INNER JOIN (SELECT * FROM Customer WHERE Gender LIKE "F") AS c ON Sale.CustomerID = c.CustomerID; 

but i think i have selected them ALL :/

1 Answer

Steven Parker
Steven Parker
231,248 Points

You have indeed created a solution that would return the correct rows. :+1: But the challenge is looking for your sub-query to return only the CustomerID so that final result will *"Select all columns from the Sale table only."

You might also try prefixing that first asterisk with "Sale.". But if that doesn't work, you might want to report it as a bug to Support.

Patrik Horváth
Patrik Horváth
11,110 Points

but if i change * to Sale.CustomerID it is not let me pass this chalange =\

Steven Parker
Steven Parker
231,248 Points

But the table in the sub-query is "Customer", not "Sale". Plus you don't need to prefix the field at all inside the sub-query, since there is only one source.

And to facilitate the most accurate answers, always provide a link to the course page you are working with.

Patrik Horváth
Patrik Horváth
11,110 Points

after getting : fd7e0c01-7ddb-460c-81c2-c11f3d124e64.rb:35:in eval': undefined methodshift' for "SQL Error: no such column: Customer":String (NoMethodError) from fd7e0c01-7ddb-460c-81c2-c11f3d124e64.rb:35:in `eval' from fd7e0c01-7ddb-460c-81c2-c11f3d124e64.rb:35:in

it worked :D, Thanks :)