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For 2023 (and 2024 ...) - we are now fully retired from IT training.
We have made many, many friends over 25 years of teaching about Python, Tcl, Perl, PHP, Lua, Java, C and C++ - and MySQL, Linux and Solaris/SunOS too. Our training notes are now very much out of date, but due to upward compatability most of our examples remain operational and even relevant ad you are welcome to make us if them "as seen" and at your own risk.

Lisa and I (Graham) now live in what was our training centre in Melksham - happy to meet with former delegates here - but do check ahead before coming round. We are far from inactive - rather, enjoying the times that we are retired but still healthy enough in mind and body to be active!

I am also active in many other area and still look after a lot of web sites - you can find an index ((here))
Caching between pages via memcached
Web2 and caching example from a Well House Consultants training course
More on Web2 and caching [link]

This example is described in the following article(s):
   • memcached - overview, installation, example of use in PHP - [link]

If you're searching for a page where you can try this code, select here

This example references the following resources:$imgname

Source code: cademo.php Module: H307

# Record number to look up
$calledfor floor($_REQUEST[calledfor] + 0); // force numeric integer!
$calledfor or $calledfor rand(3006,3012); // Fallback value!

# The database accessor is used if we do NOT have data in cache
function dbfetch ($recno) {
$c mysql_connect("","wellho","xxxxxxxx");
$qr mysql_query("select iid,filename,descriptor ".
"from im_library where iid = $recno",$c);
$row mysql_fetch_assoc($qr);
$value "$row[filename] $row[descriptor]";
        return (

$memcache = new Memcache;
if (
$memcache->connect(''11211)) {
$q "connected (memcache daemon is running)";
        if (
$gotten $memcache->get("demo:$calledfor")) {
### Daemon running and provided data from cache
$say "key $calledfor retrieved from memcached";
        } else {
### Daemon running but it was NOT cached
$say "key $calledfor from database (was NOT cached)";
# Never mind - fetch it and store for next time!
$gotten dbfetch($calledfor);
} else {
### No Daemon running - just fetch from database!
$q "failed (sorry - daemon is not running)";
$say "key $calledfor fetched from database";
$gotten .= dbfetch($calledfor);
# No point in trying to save it - cacher isn't running!

# Following code is common code whatever the source!
# and represents the application

$parts explode(" ",$gotten) ;
$imgname array_shift($parts);
$imgtag "<img src=$imgname>";
$text htmlspecialchars(implode(" ",$parts));
<style type="text/css">
h1 {
        font-family: Arial, Helvetica, sans-serif;
        font-size: 36px;
        font-weight: bold;
        color: #CC00CC;
.tabtext {
        font-family: Arial, Helvetica, sans-serif;
        font-size: 12px;
        color: #004400;
<title>Memcache demonstration in PHP</title>
--- daemon connect status: <?= $q ?> ---<br>
--- <?= $say ?> ---<br>
--- value is: <?= $gotten ?> ---</center><hr>
<h1>Caching database queries in memory in PHP</h1>
<table class=tabtext><tr><td valign=top>
<?= $imgtag ?><br>
<b><?= $text ?></b>
</td><td valign=top>
If you have a busy server with repeated database queries,
you may wish to use the <b>memcached</b> daemon.  This
service allows you to store a query's results in memory
(and even to share the cache between computers) so that
you don't have to keep repeating SQL and disc accesses.
Memcached is used on many very busy sites - it's ideal
for blog articles (where the recent ones will be cached),
images, and so on.
This is a demonstration of memcached in use, via a PHP
web page.  It's provided by Well House Consultants who
cover such topics on their
<a href=>PHP
techniques workshop</a> or on private courses.
You are also very welcome to view the source code (link
below) and read a little more about it in our blog
<a href=>here</a>.
The home page of memcached is
<a href=>here</a>.


Learn about this subject
This module and example are covered on our public PHP Techniques course. If you have a group of three or more trainees who need to learn the subject, we can also arrange a private or on site course for you.

Books covering this topic
Yes. We have over 700 books in our library. Books covering PHP are listed here and when you've selected a relevant book we'll link you on to Amazon to order.

Other Examples
This example comes from our "Web2 and caching" training module. You'll find a description of the topic and some other closely related examples on the "Web2 and caching" module index page.

Full description of the source code
You can learn more about this example on the training courses listed on this page, on which you'll be given a full set of training notes.

Many other training modules are available for download (for limited use) from our download centre under an Open Training Notes License.

Other resources
• Our Solutions centre provides a number of longer technical articles.
• Our Opentalk forum archive provides a question and answer centre.
The Horse's mouth provides a daily tip or thought.
• Further resources are available via the resources centre.
• All of these resources can be searched through through our search engine
• And there's a global index here.

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