1-pagination.php

<?php

private function iterateSubmissions()
{
  $nStartFrom = 0;
  $nLimit = 500;
  
  do {
    $sQuery = 'SELECT blahblah FROM someTable WHERE blahblah = "somecondition" LIMIT ' . $nStartFrom . ', ' . $nLimit;
    
    $oResults = $this->oDB->query($sQuery);
    
    while ($kRow = $oResults->fetch(\PDO::FETCH_ASSOC)) {
      yield $kRow;
    }
    
    $nStartFrom += $nLimit;
    
    echo 'Start updated to ' . $nStartFrom;
    
  } while ($kRow !== false);
}

2-coworkers.php

<?php

private function coworkersMethod()
{
  $nStartFrom = 0;
  $nLimit = 500;
  $bHasResults = true;
  
  do {
     $sQuery = 'SELECT blahblah FROM someTable WHERE blahblah = "somecondition" LIMIT ' . $nStartFrom . ', ' . $nLimit;
    
    $oResults = $this->oDB->query($sQuery);
    
    if ($oResults->rowCount()) {
    
      while ($kRow = $oResults->fetch(\PDO::FETCH_ASSOC)) {
        yield $kRow;
      }
      
      $nStartFrom += $nLimit;
    } else {
      $bHasResults = false;
    }
  } while ($bHasResults);
}