Unable to execute fetch(PDO::FETCH_ASSOC) and not updating csv file - php

Question

// First, prepare the statement, using placeholders
$query = "SELECT * FROM tableName";
$stmt = $this->connection->prepare($query);
// Execute the statement
$stmt->execute();
var_dump($stmt->fetch(PDO::FETCH_ASSOC));
while ($row = $stmt->fetch(PDO::FETCH_ASSOC))
{
echo "Hi";
// Export every row to a file
fputcsv($data, $row);
}
Is this correct way to do and if yes than why do I get false value for var_dump and than it does not go into while loop and does not write into csv file.
Any suggestions ?

Answer 1

One thing that is missing is that you first need to open the csv file:
$fp = fopen('file.csv', 'w');
then you can put data into it:
fputcsv($fp, $data);
As for the var_dump printing out false, you would have to provide more information about what objects you are actually using I think. (ie: what is $this->connection ?)
I don't know if this will help, but try to do it without the $this->connection:
$config['database'] = 'sakila';
$config['host'] = 'localhost';
$config['username'] = 'root';
$config['password'] = '';
$d = new PDO('mysql:dbname='.$config['database'].';host='.$config['host'], $config['username'], $config['password']);
$query = "SELECT * FROM actor";
$stmt = $d->prepare($query);
// Execute the statement
$stmt->execute();
var_dump($stmt->fetch(PDO::FETCH_ASSOC));
$data = fopen('file.csv', 'w');
while ($row = $stmt->fetch(PDO::FETCH_ASSOC))
{
echo "Hi";
// Export every row to a file
fputcsv($data, $row);
}