This advanced SQL exercise is part of the book: Advanced SQL – Practical Techniques and Use-Cases, which includes 100 day-to-day SQL challenges (and solutions), need-to-know advanced features, and key concepts.
 

A space station manager uses the following table to specify various types of spaceships at his disposal:


CREATE TABLE starship_classes
(Id INT IDENTITY(1,1),
Class1 VARCHAR(25),
Class2 VARCHAR(25))
GO

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