Why Is My Dropdown Box Empty When Populating from a MySQL Table in PHP?

Populating a Dropdown Box from a MySQL Table in PHP: Troubleshooting

When attempting to populate a dropdown box from a MySQL query in PHP, users may encounter difficulties resulting in an empty dropdown. Here's a solution to resolve this issue, focusing on debugging and understanding the code's functionality.

The provided query retrieves the PcID column from the PC table. To populate the dropdown box, you'll need a PHP script that connects to the database, executes the query, and generates HTML options for the dropdown.

Here's a sample script:

<?php

// Establish database connection
mysql_connect('hostname', 'root', 'password');
mysql_select_db('database-name');

// Execute the query
$sql = "SELECT PcID FROM PC";
$result = mysql_query($sql);

// Generate dropdown options
echo "<select name='PcID'>";
while ($row = mysql_fetch_array($result)) {
    echo "<option value='" . $row['PcID'] . "'>" . $row['PcID'] . "</option>";
}
echo "</select>";

?>

Explanation:

• Connection: We start by connecting to the database using the mysql_connect and mysql_select_db functions.
• Query Execution: The query to retrieve PcID values is executed using mysql_query.
• Loop and Option Generation: The while loop iterates through the query results. For each row, we generate an HTML option tag with the retrieved PcID as both the value and displayed text.
• Dropdown Output: The generated options are echoed into a HTML select box with the name PcID.

Ensure that your script's code is correct and that you have the proper database credentials, and you should see the dropdown box populated with PcID values.

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