break; hangs page

[sharyn]

Anyone ever hear of the "break;" command hanging a page? I exit a loop upon a condition and it does just fine for a few iterations, but at some point, I ask it to exit the loop with a "break;" and my page is hung.

I first tried it with a "do" loop, a "while" loop, a "for" loop. Same thing, at some point, it just hangs.... It works fine and all of a sudden it doesn't and always in the same place.

Any ideas?

Thanks a million,
sharyn

[bubblenut]

Never heard of anything similar, you'll have to post some code up. I can only guess that it's slipping into an infinite loop, maybe you're breaking out of a nested switch or something? Regardless, post up the offending code and we'll see what can be done.

[sharyn]

ok, here it is in all it's messyness...

You have to realize that there are quite a bit of error checking statements and some of the wierdness of it is because I'm trying to isolate the cause of the hanging....

$trQ = sprintf("SELECT count(*) FROM TileRegionTable WHERE North<=%f and South>=%f and East<=%f and West>=%f and East>West",
               $trtN, $trtS, $trtE, $trtW);
$trRes = mysql_query($trQ,$_SESSION['trDB']->link);  $Error = mysql_error();
$trRow = mysql_fetch_array($trRes);
$trCount = $trRow[0];

$trQ = sprintf("SELECT * FROM TileRegionTable WHERE North<=%f and South>=%f and East<=%f and West>=%f and East>West",
               $trtN, $trtS, $trtE, $trtW);

$trRes = mysql_query($trQ,$_SESSION['trDB']->link);  $Error = mysql_error();


while ( 1 )
{
//for ($Looper=0; $Looper < $trCount; $Looper++ )
//{
  echo "<br>Hello World ".$Looper."<br>"; ob_flush(); flush();
  $CheckThisDB = Make_Table_Name($trRow['North'], $trRow['South'], $trRow['East'], $trRow['West']);
  // Get the next resolution down in our list of resolutions 
  $AnyImagesQ = sprintf("SELECT * FROM %s WHERE North<=%f and South>=%f and East<=%f and West>=%f and East>West and round((Resolution*%d))<%10.2f ORDER BY Resolution DESC", 
                $CheckThisDB, $N, $S, $E, $W, $TenTimes, $Resolution*$TenTimes); 

  if ( $_SESSION['Debug'] > $DebugThreshold )      echo "2 $AnyImagesQ<br>"; ob_flush(); flush();
  $AIResult = mysql_query($AnyImagesQ,$_SESSION['AIdb']->link); 
  echo "Iam here :  1<br>"; ob_flush(); flush();
  $AIRow = mysql_fetch_array($AIResult);
  echo "Iam here :  2<br>"; ob_flush(); flush();


  // Reset to the new higher resolution if it is the highest so far
  if ( $AIRow != NULL )
  {
    echo "Iam here :  3<br>"; ob_flush(); flush();
    $NextHighRes = (($AIRow['Resolution'] > $NextHighRes) ? $AIRow['Resolution'] : $NextHighRes);
     echo "Iam here :  4<br>"; ob_flush(); flush();
    Store_Session_Var($NextHighRes, "Resolution");
     echo "Iam here :  5<br>"; ob_flush(); flush();
    if ( $_SESSION['Debug'] > $DebugThreshold ) echo "Resolution is now = $NextHighRes<br>";
  }
  echo "Iam here :  6<br>"; ob_flush(); flush();

  $trRow = mysql_fetch_array($trRes, MYSQL_ASSOC); $Error = mysql_error(); if ($Error) echo "ERROR fetch :: $Error<br>"; ob_flush(); flush();
  echo "Iam here :  7 - $Looper  [trrow = $trRow]<br>"; ob_flush(); flush();
  echo "Iam here :  8 - $Looper<br>"; ob_flush(); flush();
  echo "Iam here :  9 - $Looper<br>"; ob_flush(); flush();
  echo "Iam here :  10 - $Looper<br>"; ob_flush(); flush();
  if ( $trRow != NULL ) { echo "Not out yet<br>";  ob_flush(); flush(); $OuttaHere = 0;}
  if ( $trRow == NULL ) { echo "outta Here<br>";   ob_flush(); flush(); $OuttaHere = 1;}

  echo "Iam here :  11 - $Looper  [trrow = $trRow]<br>"; ob_flush(); flush();

  if ( $OuttaHere ) break;

  $Looper = $Looper + 1;

  ob_flush(); flush();


} 

 echo "<br><br>Out Of LOOP<br><br>";

So the output is as follows...

When it goes through correctly, you see all the numbers and it exits nicely saying "Out Of LOOP". In other words, trRow is returning with matches and so is AIRow.

When it hangs you see numbers 1, 2, 6 - 11 until trRow is null, then it never exits or gets to "Out Of LOOP", but sits there until time out. I got rid of the time out to see if maybe something was taking too long, but it sat there forever. It's not running through an infinite loop as far as I can tell, because it never runs through any other iteration... it just sits there. When it hangs, it never goes through numbers 3-5 because AIRow returns null.

[halojoy]

<?php

$trQ = sprintf("SELECT count(*) FROM TileRegionTable WHERE North<=%f
  and South>=%f and East<=%f and West>=%f and East>West",
  $trtN, $trtS, $trtE, $trtW);
$trRes = mysql_query($trQ,$_SESSION['trDB']->link);  

$Error = mysql_error();
$trRow = mysql_fetch_array($trRes);
$trCount = $trRow[0];

$trQ = sprintf("SELECT * FROM TileRegionTable WHERE North<=%f
  and South>=%f and East<=%f and West>=%f and East>West",
  $trtN, $trtS, $trtE, $trtW);

$trRes = mysql_query($trQ,$_SESSION['trDB']->link);  

$Error = mysql_error();

// While loop start
while ( 1 ) {

//for ($Looper=0; $Looper < $trCount; $Looper++ )
//{

  echo "<br>Hello World ".$Looper."<br>";
  ob_flush();
  flush();

  $CheckThisDB = Make_Table_Name($trRow['North'], $trRow['South'],
 $trRow['East'], $trRow['West']);

// Get the next resolution down in our list of resolutions 
  $AnyImagesQ = sprintf("SELECT * FROM %s WHERE North<=%f and South>=%f
  and East<=%f and West>=%f and East>West
  and round((Resolution*%d))<%10.2f ORDER BY Resolution DESC",
  $CheckThisDB, $N, $S, $E, $W, $TenTimes, $Resolution*$TenTimes); 

if ( $_SESSION['Debug'] > $DebugThreshold ) {
    echo "2 $AnyImagesQ<br>";
}

  ob_flush();
  flush();

  $AIResult = mysql_query($AnyImagesQ,$_SESSION['AIdb']->link); 
  echo "Iam here :  1<br>";
  ob_flush();
  flush();

  $AIRow = mysql_fetch_array($AIResult);
  echo "Iam here :  2<br>";
  ob_flush();
  flush();

// Reset to the new higher resolution if it is the highest so far
if ( $AIRow != NULL )  {
    echo "Iam here :  3<br>";
}

  ob_flush();
  flush();

  $NextHighRes = (($AIRow['Resolution'] > $NextHighRes) ? $AIRow['Resolution'] :
    $NextHighRes);
  echo "Iam here :  4<br>";
  ob_flush();
  flush();

  Store_Session_Var($NextHighRes, "Resolution");
  echo "Iam here :  5<br>";
  ob_flush();
  flush();

if ( $_SESSION['Debug'] > $DebugThreshold ) {
        echo "Resolution is now = $NextHighRes<br>";
}

  echo "Iam here :  6<br>";
  ob_flush();
  flush();

  $trRow = mysql_fetch_array($trRes, MYSQL_ASSOC);
  $Error = mysql_error();

 if ($Error) {
    echo "ERROR fetch :: $Error<br>";
 }

  ob_flush();
  flush();

  echo "Iam here :  7 - $Looper  [trrow = $trRow]<br>";
  ob_flush();
  flush();

  echo "Iam here :  8 - $Looper<br>";
  ob_flush();
  flush();

  echo "Iam here :  9 - $Looper<br>";
  ob_flush();
  flush();

  echo "Iam here :  10 - $Looper<br>";
  ob_flush();
  flush();

  if ( $trRow != NULL ) {
        echo "Not out yet<br>";
        ob_flush();
        flush();
        $OuttaHere = 0;
  }

  if ( $trRow == NULL ) {
         echo "outta Here<br>";
         ob_flush();
         flush();
         $OuttaHere = 1;
   }

  echo "Iam here :  11 - $Looper  [trrow = $trRow]<br>";
  ob_flush();
  flush();

  // This if does nothing, as far as halojoy can see
  // It would if you use  break 2;  (= break out of two loop levels)
  if ( $OuttaHere ) {
      break;
  }

  $Looper = $Looper + 1;
  ob_flush();
  flush();

}  // End while loop

 echo "<br><br>Out Of LOOP<br><br>";

?>

Was really a messy code.
You shouldnt put several php statements on same line
and you SHOULD put { and } around what should be done in each If($var) statement.
At least as long as you are new to php programming.

One day when you are sure what you are doing,
you might be able to simplify coding style.

/halojoy
wouldnt see him write code, like this is in first version here
and yet, halojoy is not a total beginner
🙂

[toxic_brain]

i think its not hanging.... it may be an INFINITE loop..

[Drakla]

toxic_brain wrote:

i think its not hanging.... it may be an INFINITE loop..

Exactly - how to you know you're ever going to hit your break condition? You've got that loop counter in there so why not use that as a safety feature and change the while to while (Looper < 1000) or something. Also what the hell is with all that ob_flush rubbish? You're not doing any output buffering, not unless it's defaulted to in php, but just put [man]ob_implicit_flush/man at the top and junk all that stuff as it makes the code sickening to look at

[bubblenut]

halojoy has actually answered the question. Read through his re-write of the code and he points out that you have a single break withing a set of two loops (the outer loop, the while, is infinite as the condition is simply true). As halojoy says, you can solve this by replacing your "break" with a "break 2" to break out of both levels of iteration.

[sharyn]

actually, despite me telling you that it's really messy because I've been trying a miliion different things to make it work so it ends up being really messy ... it's not in an infinite loop.. I completely took it out of a loop and it still hangs.... I tried a for loop, I tried a do loop, I tried a while loop, I gave up loops entirely... but it still hangs...

Please resist commenting on the messiness of my code. I know it's messy, it didn't start out that way, I am just at the end of my rope with trying to make it work and am just trying different things... I left stuff in there so people can see that I am trying different things. It really isn't helpful to tell me my code is sickening or that it is awful ... really, it doesn't...

so... it isn't in an infinite loop.. it's now not in a loop at all... I just can't see what's making it hang..

[cmancone]

How sure are you that you are "hanging"? Did you read bubblenut's comment about halojoy's comment? Anyway, my recommendation would be to do this without while ( 1 ). It can be a rather dangerous way of doing things. Granted though, you probably don't want to re-write this. However, there is a very simple way to make sure whether or not you are in an infinite loop. Change it to this:

$randomnumber = 0;
while( $randomnumber < 1000 )
{
     ++$randomnumber;

// various codes

}
print "yeah, I'm out of my loop!!!!";

Personally, I find the idea of php "hanging" because of a break very unlikely. Sometimes complicated programs just don't work how we expect them to. Try it out with the above change, and see if your loop stops "hanging", which I would guess it will. First however, try out halojoy's suggestion, if you haven't already. Change your break to "break 2", to break out of the if and the while.

[sharyn]

ok all, I took it out of the loop (see my post above cmancone's).. There is no loop... the page just hits a point and sits there with the spinner continuing to spin. That's what gets me... no loop, but as I print out statements after every command (trying to figure out where it's stopping), it never hits the statement after "Iam here : 11" to reach the statement that is " echo "<br><br>Out Of LOOP<br><br>";"

Remember, there is NO loop now....

Could accessing the database and returning a null do anything at all? (I wouldn't think so... but... there are experts out there who may know better)

[halojoy]

you have changed code
but still problem

can you show me code
there is not anything 'magically' about php programming.
Script will always do what we tell
And there is always a corrcet way to tell PHP to do what we want

If you have a 'mysql problem', I will not help you
( I do not know howto use that "mysql.bin program" in your PC
and I do notwant to and I do not need to know anything beginning in my and ending in database
because my 'php.exe program' does it all so well, and with less problem when working without disturbance)

But if you give your new php code, me or somebody else, with 95% chance
will tell you how to fix it
You have a good script running tomorrow !
🙂 this is a promise

/halojoy

[sharyn]

Ok, for all you cringers out there who hate messy code.. and that includes me... I cleaned it up a little

function Scan_DB($trtN, $trtS, $trtE, $trtW, $N, $S, $E, $W, $TenTimes, &$Resolution)
{
  $trQ = sprintf("SELECT count(*) FROM TileRegionTable WHERE North<=%f and South>=%f and East<=%f and West>=%f and East>West",
                 $trtN, $trtS, $trtE, $trtW);
  $trRes = mysql_query($trQ,$_SESSION['trDB']->link);  

  $Error = mysql_error();
  $trRow = mysql_fetch_array($trRes);
  $trCount = $trRow[0];  

  $trQ = sprintf("SELECT * FROM TileRegionTable WHERE North<=%f and South>=%f and East<=%f and West>=%f and East>West",
                 $trtN, $trtS, $trtE, $trtW);
  $trRes = mysql_query($trQ,$_SESSION['trDB']->link);  

  $Error = mysql_error();

  if ($Error) echo "Error :1: $Error<br>";
  else
  {

$trRow = mysql_fetch_array($trRes, MYSQL_ASSOC); 
$Error = mysql_error();
if ($Error) echo "Error :2: $Error<br>";
else
{
  if ( $trRow != NULL )
  {
    $NextHighRes = 0;

    $CheckThisDB = Make_Table_Name($trRow['North'], $trRow['South'], $trRow['East'], $trRow['West']);

    // Get the next resolution down in our list of resolutions 
    $AnyImagesQ = sprintf("SELECT * FROM %s WHERE North<=%f and South>=%f and East<=%f and West>=%f and East>West and round((Resolution*%d))<%10.2f ORDER BY Resolution DESC", 
                          $CheckThisDB, $N, $S, $E, $W, $TenTimes, $Resolution*$TenTimes); 

    $AIResult = mysql_query($AnyImagesQ,$_SESSION['AIdb']->link); 
echo "1<br>";
        $AIRow    = mysql_fetch_array($AIResult);
echo "2<br>";


    // Reset to the new higher resolution if it is the highest so far
    if ( (!empty($AIRow)) && ($AIRow != NULL) )
    {
echo "3<br>";
          $NextHighRes = (($AIRow['Resolution'] > $NextHighRes) ? $AIRow['Resolution'] : $NextHighRes);
echo "4<br>";
          Store_Session_Var($NextHighRes, "Resolution");
echo "5<br>";
        }
echo "6<br>";

    $trRow = mysql_fetch_array($trRes, MYSQL_ASSOC); 
echo "7<br>";
        $Error = mysql_error(); 
        if ($Error) echo "ERROR fetch :: $Error<br>";

    if ( $trRow != NULL ) 
    { 
      echo "There is data<br>";
      $OuttaHere = 0;
    }
echo "8<br>";
        if ( $trRow == NULL ) 
        { 
          echo "There is no more data<br>";
          $OuttaHere = 1;
        }

echo "9 :: OuttaHere = $OuttaHere<br>";

echo "<br><br>Out Of LOOP<br><br>";

    $Resolution = $NextHighRes;

    // We need this to check the smaller resolutions < 1 for some weird reason. I have no clue why
    if ( $Resolution < 1 )
    {
      $TenTimes = 1;
      $ResTemp  = $Resolution;
      do
      {
        $TenTimes *= 10;
        $ResTemp = $Resolution * $TenTimes;
      } while ( $ResTemp < 1 );
      $CIBData = 1;
      Store_Session_Var($CIBData, "CIBData");    if ( $_SESSION['Debug'] > $DebugThreshold )    echo "ssv-cibdata 3<br>";
    }
    else { $TenTimes = 1.0;  $CIBData = 0; Store_Session_Var($CIBData, "CIBData");    if ( $_SESSION['Debug'] > $DebugThreshold )    echo "ssv-cibdata 4<br>";}

  } // $trRow != NULL
} // e: Error 2 : fetch_array($trRes)
  } // e: Error 1 : mysql_query($trQ)
  /*---*/     

  echo "Out of SCAN_DB<br>"; ob_flush(); flush();
  return(0);
}//Scan_DB

I stuck the echo numbers out to the margin so you all can see when I say it hits numbers x,y,z where numbers x,y,z are easily... do not hassle me on this point and tell me they shouldn't stick out... it's not going to help solve the problem and it certainly isn't the problem... thanks

When data is returned to AIRow, no problem. You see numbers 1 - 9 then Out Of LOOP.

When NULL is returned to AIRow, You only see numbers 1, 2, 6, 7, 8 and 9 but you never see Out Of LOOP....

this is the mystery....

[bubblenut]

If you see the echo message with 9 in you will see the message with "Out Of LOOP" in, I'm sorry, but that just is the case. There is nothing between the two statements so there is nothing which can stop then flow. If this is really happening as you say it is the only thing I can think for you to do is to set error_reporting(E_ALL) at the top of the page and see what it gives you.

[sharyn]

BubbleNut... yep.. exactly... that's why it's a mystery. I'll try the error_reporting(E_ALL) and see what happens...