The Web Server Environment - Database Processing: Fundamentals, Design, and Implementation - page 473

Displaying the Results
Now that the RecordSet name $RecordSet has been created and populated, we can process the
$RecordSet collection with the following code:

<!-- Page Headers -->

<H1>

The View Ridge Gallery ARTIST Table

</H1>

<hr />

<H2>

ARTIST

</H2>

<?php

// Table headers

echo "<table class='output' border='1'>

<tr>

<th>LastName</th>

<th>FirstName</th>

<th>Nationality</th>

</tr>";

// Table data

while($RecordSetRow = odbc_fetch_array($RecordSet))

{

echo "<tr>";

echo "<td>" . $RecordSetRow['LastName'] . "</td>";

echo "<td>" . $RecordSetRow['FirstName'] . "</td>";

echo "<td>" . $RecordSetRow['Nationality'] . "</td>";

echo "</tr>";

}

echo "</table>";

The HTML section defines the page headers, and the PHP section defines how to display
the SQL results in a table format. Note the use of the PHP command echo to allow PHP to use
HTML syntax within the PHP code section. Also note that a loop is executed to iterate through
the rows of the RecordSet using the PHP variable $RecordSetRow.
Disconnecting from the Database
Now that we have finished running the SQL statement and displaying the results, we can end
our ODBC connection to the database with the code:

// Close connection

odbc_close($Conn);

?>

The basic page we have created here illustrates the basic concepts of using ODBC and
PHP to connect to a database and process data from that database in a Web database process-
ing application. We can now build on this foundation by studying PHP command syntax and
incorporating additional PHP features into our Web pages. 7

Challenges for Web Database Processing
Web database application processing is complicated by an important characteristic of HTTP.
Specifically, HTTP is stateless; it has no provision for maintaining sessions between requests.
Using HTTP, a client at a browser makes a request of a Web server. The server services the

7 For more information on PHP, see the PHP documentation at www.php.net/docs.php .