为什么这个简单的查询不起作用?

I have this query, and I can't find anything wrong with it, yet it prints out the die() text when it runs...

$result = mysql_query($cxn, "SELECT * FROM news_table") or die("Query not working.");

My guess is that you're mixing MySQL_ with MySQLi_ from what I seen in your questions, where you're using MySQLi_ functions

One of your other questions:

Connection is the second argument. You have it backwards.

$result = mysql_query("SELECT * FROM news_table", $cxn) or die("Query not working.");