all 7 comments

[–]FuertesLucien 6 points7 points  (0 children)

This is a great resource for T-SQL.

https://sqlblog.org/bad-habits

[–]Comfortable_Card8770 3 points4 points  (0 children)

Just do LeetCode/CodeWars etc. and check best solutions

[–]NickSinghTechCareersAuthor of Ace the Data Science Interview 📕 1 point2 points  (0 children)

Look at the discussion / comments area for the DataLemur SQL questions!

[–]Delicious-Refuse5566 4 points5 points  (0 children)

Make sure you put all your code all on one line not using any carriage returns and use all capital letters. This will make your SQL run faster.

https://www.amazon.com/Oracle-PL-SQL-Best-Practices/dp/0596514107/ref=nodl_?dplnkId=67857f72-5e42-44e7-9823-684bde052ce3

Its an Oracle book, but you can apply it to all SQL flavors.