What is a SQL injection and how do I code one?

Question

I am nearly done learning SQL and what took my attention is SQL vulnerabilities and SQL injections (SQLi), how is it made?

Answer 1

nothing.. just knowledge of sql and a poorly designed website

see here for more info: https://www.w3schools.com/sql/sql_injection.asp

Answer 2

it is made possible by poor design.
i.e not checking user input for validity before processing

Answer 3

It is usually done on website forms where the user has to insert information. Instead of information like name, you put sql commands.

Answer 4

Explainxkcd's comments (for the webcomic xkcd) are usually pretty helpful:

https://www.explainxkcd.com/wiki/index.php/327:_Exploits_of_a_Mom

Answer 5

I see! I get it clearly now! Thanks guys!

Answer 6

Still confused though. ._.

Answer 7

Yes, but what programs do I need to do so?