SQL Guide files invalid

The file SQL Guide - ALTER TABLE is totally messed up since the user removed the images, a PR #30349 made changes to it which makes it better, but not fixes it.

We want the whole file to have statements like that we have now for Remove a column:

Additionally, we want the PR to be formatted properly, such as each of these:

• 
• 

to be put in a list form

And this warning note: to be moved to a new line

EDIT:

On a closer look, this problem is in many SQL challenges which are there. Examples:

• 1
• 2 In (2), the images should be removed, we do not want to host them on GitHub

We can either have just the text command or text tables like in: here

[raisedadead]

There are so many compelling reasons to avoid images when you can:

1. Images hurt a11y. You can add alt text ‘Image explaining … your reason here’, but that’s about it.
2. They are difficult to maintain and easily get outdated. Imagine updating text regularly.
3. They hurt performance. Text is fast to deliver over network vs images.

There are probably lot more reasons, but you can imagine.

[ritute]

Sent an email to the author to see if we can have the images recovered and then we can create text-based tables off of them (so that we don’t have to start from scratch).