please if you need the data you can find it online chinook database. the query must have join and one aggregation.

Artist Album Albumld Artistid Name MediaType MediaTypeld Name Title Artistid Track Trackld Name Albumid Media Typeld Genreld Composer Milliseconds Bytes UnitPrice Playlist Playlistld Name Playlist Track Playlistld Trackld Genre Genreld Name InvoiceLine InvoiceLineld Invoiceld Trackld UnitPrice Quantity Employee Employeeld Last Name FirstName Title ReportsTo Birth Date HireDate Address City State Country PostalCode Phone Fax Customer Customerld FirstName LastName Company Address City State Country PostalCode Phone Fax Email SupportRepld Invoice Invoiceld Customerld InvoiceDate BillingAddress Billing City BillingState Billing Country Billing PostalCode Total Email Question 3: Who is the best customer? The customer who has spent the most money will be declared the best customer. Build a query that returns the person who has spent the most money. I found the solution by linking the following three: Invoice, InvoiceLine, and Customer tables to retrieve this information, but you can probably do it with fewer! Check Your Solution The customer who spent the most according to invoices was Customer 6 with 49.62 in purchases