Reusing MYSQL queries on the same page - php

Question

I have a header.php and a footer.php file being included on the same page, they both return some of the same information. Specifically I use this query in each file.
<?php
$q3 = "SELECT page_id, show_id, link_title FROM pages as p WHERE show_id = 1";
$r3 = #mysqli_query ($dbc, $q3); // Run the Query.
while ($nav = mysqli_fetch_array($r3, MYSQLI_ASSOC)) {
echo"<li>{$nav['link_title']}</li>"
}
?>
This is to show the pages in both the header and footer.
However SOMETIMES the second query in the footer returns a "Couldn't fetch mysqli", sometimes it works, sometimes it doesn't. I was wondering should I be using something like mysqli_free_result() would that be better practice?
Even more, is it good practice to free the result after every query? Is there a better way to use the same result from different pages and <?php // ?> tags?
Also, I get the error "too many mysql connections error" every now and then? Is this because I am not closing connections after queries are ran?

Answer 1

You could begin with removing the # from your code. Error suppression is slow and harmful practice.
If you inlcude's are in same scope, you can just save the value of first in some variable, and check in second , if variable has been set.
content of header.php
$storage = '';
$query = "SELECT page_id, show_id, link_title FROM pages as p WHERE show_id = 1";
if ( $result = mysqli_query ($dbc, $query))
{
while ($nav = mysqli_fetch_array($result, MYSQLI_ASSOC))
{
$item = "<li>{$nav['link_title']}</li>";
$storage .= $item;
echo $item;
}
}
else
{
echo 'Query has failed !';
}
content of footer.php
if ( isset( $storage ) && count( $storage ))
{
echo $storage;
}
else
{
echo 'Query has failed !';
}
Read about include() in the fine manual.
And please , stop writing that this procedural perversion. Learn how to do OOP and read about PDO.

Answer 2

Run the query only once, prior to including the header and footer and store the results in a variable - you can use them as many times as you want after that.
mysqli_free_result() should be used only if you have a really large result set, as PHP would take care of free-ing it after it's no longer needed and manually doing this every time just creates extra overhead.
You are getting the "too many connections" error because you're probably opening multiple connections as you do with repeating the same query - create just one before including any other script and just reuse it. You should use the standard mysql extension with mysql_pconnect() for an even better solution to this one ... otherwise - yes, close the connection after you no longer need it.