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Databases

James Head
James Head
18,872 Points
Posted by James Head
James Head
18,872 Points

Querying Relational Databases SubQueries Question Help

Im stuck on question 3/4 in the Querying Relational Databases SubQueries course.

The question is:

"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 along with IN to list all sales to female customers. (Gender = 'F') Select all columns."

My answer is:

"SELECT * FROM Sale WHERE SaleID IN (SELECT CustomerID FROM Customer WHERE Gender = 'F');"

However I'm getting the following error:

"Your query didn't return all columns from the Sale table for who's CustomerIDs belong to people who identify as female!"

Please could someone help!

Thank you

2 Answers

Umesh Ravji
Umesh Ravji
42,386 Points
Umesh Ravji
Umesh Ravji
42,386 Points 
SELECT * FROM Sale WHERE **SaleID** IN (SELECT CustomerID FROM Customer WHERE Gender = 'F');

You are obtaining a collection of CustomerID's from the subquery, but then you are selecting customers from the Sale table based on SaleID when you should be selecting them based on CustomerID

James Head
James Head
18,872 Points
James Head
James Head
18,872 Points

Great, thank you Umesh.

Sean M
Sean M
7,344 Points
Sean M
Sean M
7,344 Points

SELECT * FROM Sale WHERE CustomerID IN (SELECT CustomerID FROM Customer WHERE Gender = 'F');

  1. Select all from sale table
  2. Specifying customer id from the customer table
  3. specifying the gender be female.

note: a single letter/char is represented in single quotation: 'F'

Kevin Gates
Kevin Gates
15,053 Points
Kevin Gates
Kevin Gates
15,053 Points

This, but with Markdown

SELECT * FROM Sale WHERE CustomerID IN
(SELECT CustomerID FROM Customer WHERE Gender = 'F');