Peculiar behavior of for loop in php

Question

I am facing a Peculiar behavior or you can say ghostly attitude of for loop in php. I am retrieving 10000 products using an API. After that I am inserting those products in my Database.Codes are working properly in localhost but creating problem in production server.I am describing it below.

$value_array = array();        
$counter=0;                
$time_start = microtime(true); 

for($j=0;$j<count($result);$j++)
{   
   if(isset($result->Item[$j]->itemID))
   {            
      $value_array[] = (int)$result->Item[$j]->itemID.','.(int)$result->Item[$j]->systemSku;  
      $counter++;
   }
   else
   {
       var_dump($result);
       die();                   
   }


   if($counter == 100)
   {
       echo $counter;
       $time_end = microtime(true);
       $execution_time = ($time_end - $time_start);
       echo '<br /><b>Total Execution Time:</b> '.$execution_time.' Sec';

       die();
   }   
}

Above code create output like below

100
Total Execution Time: 39.075633049011 Sec

But if I change the code like below, I am getting a white page (No output).

    $value_array = array();        
    $counter=0;                
    $time_start = microtime(true); 

    for($j=0;$j<count($result);$j++)
    {   
       if(isset($result->Item[$j]->itemID))
       {            
          $value_array[] = (int)$result->Item[$j]->itemID.','.(int)$result->Item[$j]->systemSku;  
          $counter++;
       }
       else
       {
           var_dump($result);
           die();                   
       }


       if($counter == 9000)  //I changed the code here 
       {
           echo $counter;
           $time_end = microtime(true);
           $execution_time = ($time_end - $time_start);
           echo '<br /><b>Total Execution Time:</b> '.$execution_time.' Sec';

           die();
       }   
    }

I changed the code like below again.

$value_array = array();        
$counter=0;                
$time_start = microtime(true); 

for($j=0;$j<count($result);$j++)
{   
  if(isset($result->Item[$j]->itemID))
  {            
    $value_array[] = (int)$result->Item[$j]->itemID.','.(int)$result->Item[$j]->systemSku;  
    $counter++;
  }
  else
  {
    var_dump($result);
    die();                   
  }

  echo $counter.'<br/>';  //I changed the code here

   if($counter == 9000)   
   {
      echo $counter;
      $time_end = microtime(true);
      $execution_time = ($time_end - $time_start);
      echo '<br /><b>Total Execution Time:</b> '.$execution_time.' Sec';

      die();
     }   
   }

I am getting output like below

all counter values
9000
Total Execution Time: 562.96646595001 Sec

What can be the problem ?? Why the first code behaving weird ??

Why retrieve 10k records and then insert into db? insert per record...? sometimes is seems more of a hassle, but much easier to troubleshoot, because (if) it will break on a record, you can see the values for that particular record, instead of sorting through thousands of records. one record set can stop a query also. so your problem can be in other places too, eg. in transporting table structure. — csaw, Apr 30 '15 at 09:41
Thanks @csaw for your response. **insert per record** needs more time than insert all record using one query. _Thanks_ — julious ceazer, Apr 30 '15 at 09:49

score 3 · Answer 1 · edited Apr 30 '15 at 09:59

3

I looks like a time limit on the script running is only enforced when no output is generated for a long time, so echoing something at regular intervals helps it finish. But that is just speculation.

I would start by checking for differences in the PHP settings of the two servers, maybe the max_execution_time setting.

You can check this using phpinfo()

edited Apr 30 '15 at 09:59

VIVEK-MDU

2,483
3
36
63

answered Apr 30 '15 at 09:30

Totoro53

338
4
17

1

Thanks @Totoro53 for your reply. This code is running good in localhost where **max_execution_time** is **500000**. I changed my Server configuration as **max_execution_time** is **500000**, but output is same as before. _Thanks_ – julious ceazer Apr 30 '15 at 10:44
1

Do you have display errors enabled on the server that produces the white page? If not, I suggest you do so at least temporarily as it may shed more light on what is going wrong. http://stackoverflow.com/questions/1053424/how-do-i-get-php-errors-to-display – Totoro53 Apr 30 '15 at 22:01
Thanks @Totoro53 for your reply. I used these codes `ini_set('display_errors',1); ini_set('display_startup_errors',1); error_reporting(-1);` I also used below codes in **php.ini** file display_errors = on display_startup_errors = on But the situation is unchanged so far. – julious ceazer May 04 '15 at 08:35

Peculiar behavior of for loop in php

1 Answers1