It’s just an example of anything you want to specify your database to do, if you wish to use it. I was just showing that the communication can go both ways, your client can request what records they would like, and you can generate a customized query to provide relevant results. Just make sure you always
Sanitize your inputs.
I personally tend to create tediously long over-explanatory variable names when I give an example. Some people say naming things is hard.