Fixing a Messy SQL Query Step by Step

In this video, you can watch as I start with a messy SQL query and take a range of steps to clean it up and improve it.

⏱ TIMESTAMPS:
00:00 - Why it's bad
00:51 - Formatting
01:27 - Move logic
02:26 - Lookup table
05:46 - Repeat
06:36 - Normalise
08:39 - Subquery
10:09 - Reuse logic
11:28 - Use the function
12:23 - Course category
14:20 - What else

🔗 VIDEO LINKS:
Use code DatabaseStar at the checkout for 25% off!

[RichardSmithers]

Wouldn't this fail if the grade was 100 - it is greater than 90, but not less than 100?

[canews]

Some of your queries have 24 rows, and some have 25 rows. Do you not see this as an issue?

[mrbartuss]

Out of curiosity, could AI do that? Have you tried?