Using an array to sort records off a database

Using MySQL Databases in PHP Pages example from a Well House Consultants training course
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Source code: sort_sql.php Module: H113


<html>
<head>
<title>PHP - reporting database records unsorted and sorted</title>
</head>
<body>
<h2>PHP demonstration - sorting outside the database</h2>
The first report that this application outputs is a seriese of records
returned by an SQL query.  In the second report, instead of outputting the
records they are saved into an associative array which is then sorted, and
the records are output in sorted order.   They key to the associative array
is the value on which the items are going to be sorted - and we have added
an extra (incrementing) value onto the end of that key to ensure that it's
unique.  If we didn't do that, and if we had two houses at the same price,
we would loose one from our sorted report.
<?php
mysql_connect("localhost","username","[password]");
mysql_select_db("wellho");

/* Reading from a database table and displaying records in
the order that they are returned */

print ("<h1>Here are some properties for sale</h1>");
$rs = mysql_query("select locate,asking,brief from sales");
while ($row = mysql_fetch_assoc($rs)) {
        print ("$row[locate] - $row[asking] - $row[brief]<br>");
        }

/* Reading from a database table and displaying records in a
different order */

print ("<h1>Here they are in price order</h1>");
$holder = array();
$rs = mysql_query("select locate,asking,brief from sales");
$count = 0;
while ($row = mysql_fetch_assoc($rs)) {
        $count++;
        $sortvalue = $row[asking].".".$count;
        $holder[$sortvalue] = "$row[locate] - $row[asking] - $row[brief]<br>";
        }
krsort($holder);
foreach (array_keys($holder) as $keyval) {
        print ($holder[$keyval]);
        }
?><br>
A couple of words of caution here: (a) You would be best advised to have
the MySQL do the sorting if you can - more efficient and (b) For a clean
application, I would much rather you had all the PHP at the top of the file,
stored the output into string variables, and output them within a template -
this is very much a sorting demo, and not meant to show best overall practise!
</body>
</html>

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* Learning to program in PHP
* PHP Programming
* MySQL
* PHP Programming
* Learning to program in PHP
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