Member Avatar for jkulp4

Hi All,

I am very new to PHP and still learning lots... :)
I am using the below code to populate a drop down list from my database.
But I am not sure how to display/send the results back to the same page.

The fields in my Database are:
Base, Owner, Cluster, Sector, Coordinates, Defenses, Notes

So based on the code below - when someone selects their Cluster I would like to display all records from database that are from that cluster. Any help is greatly appreciated.
Here is code I have:

<?php

//Populates drop down choice from database field

//Database connection string is here.

$query = "select DISTINCT Cluster FROM Starbase";
$results = mysql_query($query, $link) or die("Error performing query");

if(mysql_num_rows($results) > 0){
echo("<select name=\"selectItem\">");
echo '<option value="">Please Select..</option>';
while($row = mysql_fetch_object($results)){
echo("<option value=\"$row->record_id\">$row->Cluster</option>");
}
echo("</select>");
}
else{
echo("<i>No values found</i>");
}
?>
  • 2 Contributors
  • 2 Replies
  • 124 Views
  • 1 Day Discussion Span
  • Latest Post Latest Post by jkulp4

Dani AI

Generated

The parse error you saw is almost always caused by an unterminated string when PHP tries to interpolate an array index inside a double-quoted string. In this thread was interpolating several $row[...] items in one long double‑quoted string, which is fragile. was right to point out the select/value mismatch: either make each option value the cluster name (and query by that), or include a record id in the dropdown and query by id — but be consistent.

A simple, robust fix is to avoid complex interpolation and build strings with concatenation while escaping output. Example (uses mysqli fetchassoc here to avoid deprecated mysql* functions):

while ($row = $result->fetch_assoc()) {
    $output .= '<li>'
        . htmlspecialchars($row['Base'], ENT_QUOTES, 'UTF-8')
        . ' - ' . htmlspecialchars($row['Owner'], ENT_QUOTES, 'UTF-8')
        . ' - ' . htmlspecialchars($row['Cluster'], ENT_QUOTES, 'UTF-8')
        . '</li>';
}

echo '<option value="' . htmlspecialchars($row['Cluster'], ENT_QUOTES, 'UTF-8') . '">'
     . htmlspecialchars($row['Cluster'], ENT_QUOTES, 'UTF-8') . '</option>';

For security and forward-compatibility switch to prepared statements (mysqli or PDO). Example outline:

$stmt = $mysqli->prepare(
  "SELECT Base,Owner,Cluster,Sector,Coordinates,Defenses,Notes FROM Starbase WHERE Cluster = ?"
);
$stmt->bind_param('s', $selectedCluster);
$stmt->execute();
$res = $stmt->get_result();

Quick checklist: make sure the <select name="..."> matches your POST key, use the same value type in the option and the WHERE clause, escape output with htmlspecialchars, and var_dump($POST) when debugging. The old mysql* extension is removed in modern PHP — migrate to mysqli/PDO and use prepared statements (mysqli prepared statements, ).

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All 2 Replies

Member Avatar for Member #120589 
<?php
$selectedItem = 0; //default
$select = '<select name="selectItem"><option value="">Please Select..</option>';
$output = "";

if(isset($_POST['submit']) && isset($_POST['selectItem'])){
	$selectedItem = intval($_POST['selectItem']);
	$results = mysql_query("SELECT ...fields you need... FROM `Starbase` WHERE `Cluster`=''")or die("Error performing query");
	if(mysql_num_rows($results) > 0){
		$output .= "<ul>";
		while($row = mysql_fetch_array($results)){
			$output .= "<li>{$row['field1']} - {$row['field1']}</li>";	
		}
		$output .= "</ul>";
	}else{
		$output = "<p>No records for this Cluster, which is very strange as it was chosen from the Database</p>";	
	}
}

//I'll keep the fetch_object here
$query = "SELECT `record_id`, `Cluster` FROM `Starbase` ORDER BY Cluster";
$results = mysql_query($query, $link) or die("Error performing query");
if(mysql_num_rows($results) > 0){
	while($row = mysql_fetch_object($results)){
		$sel = ($selectedItem == $row->record_id) ? ' selected="selected"' : '';
		$select .= "<option value=\"{$row->record_id}\"$sel>{$row->Cluster}</option>";
	}
}
$select .= "</select>";
?>

<form method="post">
	<?php echo $select;?>
	<input type="submit" name="submit" value="Submit Me" />
</form>

<?php echo $output;?>

Why are you using SELECT DISTINCT on the Cluster? I hope you haven't been inputting this field individually every time. If so, use a relational model to maintain the data easily. OK, this means using JOINS in your SQL, but that's a lot better than duplicating data.

Member Avatar for jkulp4

Thank you for the help - I must still be doing something wrong as I am receiving the following error:

Parse error: syntax error, unexpected T_STRING, expecting ']' in /home/a5063282/public_html/test/test.php on line 20

Would you mind reviewing for my mistake?

<?php
//Database connection string is here

   $selectedItem = 0; //default
    $select = '<select name="selectItem"><option value="">Please Select..</option>';
    $output = "";
     
    if(isset($_POST['submit']) && isset($_POST['selectItem'])){
    $selectedItem = intval($_POST['selectItem']);
    $results = mysql_query("SELECT * FROM `Starbase` WHERE `Cluster`=''")or die("Error performing query");
    if(mysql_num_rows($results) > 0){
    $output .= "<ul>";
    while($row = mysql_fetch_array($results)){
    $output .= "<li>{$row['Base']} - {$row['Owner']} - {$row['Cluster]} - {$row['Sector']} - {$row['Coordinates']} - {$row['Defenses']} - {$row['Notes']}</li>";
    }
    $output .= "</ul>";
    }else{
    $output = "<p>No records for this Cluster, which is very strange as it was chosen from the Database</p>";
    }
    }
     
    //I'll keep the fetch_object here
    // I am NOT SURE whether to leave this or take out?

    $query = "SELECT `record_id`, `Cluster` FROM `Starbase` ORDER BY Cluster";
    $results = mysql_query($query, $link) or die("Error performing query");
    if(mysql_num_rows($results) > 0){
    while($row = mysql_fetch_object($results)){
    $sel = ($selectedItem == $row->record_id) ? ' selected="selected"' : '';
    $select .= "<option value=\"{$row->record_id}\"$sel>{$row->Cluster}</option>";
    }
    }
    $select .= "</select>";
    ?>
     
    <form method="post">
    <?php echo $select;?>
    <input type="submit" name="submit" value="Submit Me" />
    </form>
     
    <?php echo $output;?>
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