Search should show a warning when writing less than X numbers of characters in order to display result?

Question

does a search functionality should show a warning when writing less than X numbers of characters in order to display result?

Answer 1

Depends, you can set a minimum number of characters to search, it will help your backend to recieve less request.

But can be harder to your users for use,for me this question is related with your business and your user can tell more about it, give opinion without this context it's hard.

So, my default answer always: investigate and prototipe with your users, they can help you much better.

Answer 2

Instead of showing an error, guide the user to start typing:

And then once enough characters have been entered, start showing suggestions in a dropdown.

You can also have placeholder characters (X amount) and have the users typing replace them, something like this:

In this example the user has started typing the word "Test" in the input.