Display COLUMN NAMES from database through PHP - php

Question

I am trying to pull all the column names from my database 'settings' and list them in PHP.
A bit of research has come up with the following:
SHOW COLUMNS FROM settings
but I don't know how to go about listing these off through PHP.
it would be helpful if any code posted was a prepared statement format, but not required.
Here is my PHP, it's giving me this error:
Notice: Undefined index: sThumbWidth in /home/demomycm/public_html/subdomains/mercury/eshop/library/classes/class.settings.php on line 204
for every field in my database.
$loadColumns = array();
$query = "SHOW COLUMNS FROM settings";
$result = $this->glob->dbConn->query($query);
if($this->glob->dbConn->errno) {
trigger_error('An error occurred whilst loading counties from the database.' . PHP_EOL . 'Query: ' . $query . PHP_EOL . 'Error[' . $this->glob->dbConn->errno . ']: ' . $this->glob->dbConn->error, E_USER_WARNING);
} elseif($result->num_rows) {
while($row = $result->fetch_assoc()) {
$loadColumns[$row['Field']];
}
return $loadColumns;
}
$loadColumnsHtml = '';
$loadColumns = $this->Settings->LoadColumns();
foreach($loadColumns as $i => $field) {
$loadColumnsHtml .= '<div class="home-stat-small-link">' . ($i + 1) . '. <strong>' . $field['Field'] . '</strong>.</div>';
}

Answer 1

use describe
DESCRIBE my_table;
Or in newer versions you can use INFORMATION_SCHEMA:
SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = 'my_database' AND TABLE_NAME = 'my_table';

Answer 2

In your code you have $loadColumns as an array.
This line does nothing: $loadColumns[$row['Field']];
Basically your getting the value in $loadColumns with the key associated with $row['Field'] and not assigning anything.
You want something like this perhaps for that line:
array_push($loadColumns,$row['Field']);
Full code below
$loadColumns = array();
$query = "SHOW COLUMNS FROM settings";
$result = $this->glob->dbConn->query($query);
if($this->glob->dbConn->errno) {
trigger_error('An error occurred whilst loading counties from the database.' . PHP_EOL . 'Query: ' . $query . PHP_EOL . 'Error[' . $this->glob->dbConn->errno . ']: ' . $this->glob->dbConn->error, E_USER_WARNING);
} elseif($result->num_rows) {
while($row = $result->fetch_assoc()) {
array_push($loadColumns,$row['Field']); //<-- this line has been changed
}
return $loadColumns;
}
$loadColumnsHtml = '';
$loadColumns = $this->Settings->LoadColumns();
foreach($loadColumns as $i => $field) {
$loadColumnsHtml .= '<div class="home-stat-small-link">' . ($i + 1) . '. <strong>' . $field['Field'] . '</strong>.</div>';
}

Answer 3

On MySQL connection (deprecated) you can use:
mysql_list_fields
On PDO (recommend) use:
$query = $dbh->prepare("DESCRIBE tablename");
$query->execute();
$tableFields = $query->fetchAll(PDO::FETCH_COLUMN);
On PDO you can also use PDOStatement::getColumnMeta(). But it has the status: EXPERIMENTAL