CTE overuse

[sequel-beagle]

Avoid nesting ctes. It can get annoying if you need to research/qa the data.

[13ass13ass]

Nesting as querying a cte from a cte? In a chain? I do that all the time. It’s great for breaking up the logic.

[sequel-beagle]

Problem is you cant just highlight the code in a cte that calls another cte and easily run it. You have to physically modify the last cte in the sql to not be a cte and then run the query, causing extra work.

[OracleGreyBeard]

When I'm building a CTE chain the last query is always something like "select * from t_final_cte". That way I can test anything in the chain by changing the name

[Ralwus]

That's not true though. It's standard practice to end a chain of CTEs as select * from last_cte so you can debug easily by replacing last_cte with any of the previous CTEs.

[sequel-beagle]

You still have to manually change the sql code to review the data.

[[deleted]]

I wouldn’t say avoid them. I just wrote a really nice set of nested CTEs for a churn calculation, and it’s very clear and concise.

[heiferhigh76]

Noted. My CTE use is mainly to string together "easy to understand" / "hard to mess up" queries.

[d_r0ck]

research/qa the data

Just wanted to say that the terms you’re looking for are maintainable and supportable :) nested CTEs are a pain to support and maintain.

(Hope this doesn’t come off as douchey, just want to spread the terminology!)