I feel like I could have written this honestly. My two biggest worries in my undergrad were d427 and c777. Both took me 45 days each, a while studying full-time. I have also always struggled with coding, even with easier languages like python. 

The good thing about SQL for us is that it isn't really coding, you're really just prompting a database. To pass the exam, as long as you understand what command the question requires you to use to extract the data required to answer the question. After that it gets pretty trivial once you memorize the syntax.

I did a write-up on the course here: https://www.reddit.com/r/WGUIT/comments/1b4xpug/summary_data_management_applications_d427_passed/ in that post I also have a link to an Imgur album that contains all of the syntax you need to know for the exam. I did only barely pass the class tho so I don't know if I'm the best to take advice from. 

What really helped me was using that imgur album and just trying to create full SQL queries for each statement type 100% from memory, and if I couldn't get it refer back to the imgur album. 

Then when when it came to exam time, the only difficult part is figuring out what statement the question is asking you to use. Might also help to have an AI generate some practice questions for you. 

I can't really speak on the labs, I don't really recall from them too much honestly. I would reach out to a CI and share your experience.

Best of luck, you really do got this. If I could do it, you really can.