I started using Common Table Expressions (CTEs) in Oracle before Microsoft SQL Server and found them easier to read than a derived table. Something about reading from the top down just clicked in my brain. As the years have passed, I’m less of a fan for one reason: troubleshooting a chained CTE with several links is hard—especially when it’s someone else’s code. Even the ones I wrote years ago fill me with unease when something breaks. Is there an easier way to break down each link in the chain when things go wrong?
This is, I would argue, the biggest inconvenience around using common table expressions. The fact that SQL Server cannot materialize the contents of CTEs is likely a more prevalent problem, but challenges in how you can troubleshoot the individual parts of common table expressions are real.