Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

Databases Using Multiple CTEs in a Query

Posted by izzy goldman
izzy goldman
12,542 Points

First CTE seems to select two field

First CTE seems to select two fields, though only group by one.... Was this doen on purpose?

1 Answer

Steven Parker
Steven Parker
231,198 Points
Steven Parker
Steven Parker
231,198 Points

Since the OrderId is a unique key in the table, there can only be one EmployeeId associated with each one, so it's not necessary to group by both of them.