Question

I’m currently learning how to build a site in PHP MySQL. However, I seem to fail to understand COUNT() as count and wouldn’t mind some further explanation.

I get the principles of COUNT, 0 || 1, and how it returns all the values that pertain to that query.

But, don’t see how COUNT as count works. Anyhow, this is how the code I’m writing goes – so we have a working example – and where I first became perplexed.

"SELECT COUNT(id) as count, id
 FROM user
 WHERE email='$email' AND password='".md5$password."'"

Answer 1

That is what is called alias which is sometimes used to show a more appealing column header to users or the calling code

SELECT COUNT(`id`) as `count`....

will print

count
--------
5

The alias standing as the column header instead of any arbitrary string: See the SQLFiddle to see the difference

From the fiddle you can see that the header column looks somehow e.g.

count(*)
--------
5