using functions to simplify CMS theming

I'm in the process of making my own CMS. I have some code that selects database rows to be echoed out on the page like so:

$query = mysql_query("SELECT * FROM posts order by id desc") or die(mysql_error()); 

However whenever I try to put this inside a function and call the function instead of using that long lines of code, nothing happens. Am I missing something with PHP functions?

function posts() {
     mysql_query("SELECT * FROM posts order by id desc") or die(mysql_error()); `
}
while($row = mysql_fetch_array(posts())) {
   $id 开发者_如何学JAVA= $row['id'];
   echo $id;
}

You need to return the result:

function posts() {
     return mysql_query("SELECT * FROM posts order by id desc") or die(mysql_error()); `
}

Without seeing your function code, it's impossible to say what the problem is, but if I had to guess based on your description, the first thing I'd check is to see if you are (a) returning $query in your function and (b) assigning the return value to something else in your calling code.

UPDATE: So, based on the code you posetd, yes, the problem is (a) above--you need to return the value. Just put "return" before the rest of the one line of code in the function and it should work.