Create Comma Seperated List from MySQL PHP

I have a list of users in my table. How would I go about taking that list and returning it as one 开发者_开发知识库PHP variable with each user name separated by a comma?

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You could generate a comma-separated list with a query:

SELECT GROUP_CONCAT(username) FROM MyTable

Or else you could fetch rows and join them in PHP:

$sql = "SELECT username FROM MyTable";
$stmt = $pdo->query($sql);
$users = array();
while ($username = $stmt->fetchColumn()) {
    $users[] = $username;
}
$userlist = join(",", $users);

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You would fetch the list from the database, store it in an array, then implode it.

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The best way I was able to figure this out was by storing the results from each col, or field, and then echoing the implode:

      $result = mysqli_query($conn, $sql) //store the result               
      $cols = array(); //instantiate an array
      while($col = mysqli_fetch_array($result)) {
          $cols[] = $col['username']; //step through results and save each username in array
      }
      echo implode(",",$cols); //turn the array into a comma separated string and echo it

This took me a while to figure out exactly how to do this. Hope it helps!