Problem with loops

PHP
1

The coding below works perfectly when the DO loop only contains an echo statement. As soon as I add the SELECT query to the DO loop it goes wrong. The DO loop performs once correctly and as does the WHILE loop before stopping.

Any ideas?


$query  = "SELECT * FROM books";
$result = mysql_query($query)
      or die('mysql error ' . mysql_error() . ' in query ' . $query);
  WHILE ($row = mysql_fetch_array($result))

  {
    $splitkeywords1 = $row['keywords'];
    $splitkeywords2 = explode(',',$splitkeywords1);
    $keyindex = -1;

  DO
    {
      $keyindex++;
      $newtab = $splitkeywords2[$keyindex];
      echo $newtab;
      $query  = "SELECT * FROM $newtab";
      $result = mysql_query($query)
        or 
       tablecreation($newtab);
    }

  WHILE ($splitkeywords2[$keyindex] != end($splitkeywords2));
  };

PS Where can I find info on the differences and uses of the different brackets - {}

2

Gentlemen,
Thanks for the solutions, all works perfectly.
I’m grateful to you.

Mike

3

() are also sometimes used for precedence in mathematical functions, as well as conditional statements (if, elseif) to encapsulate (and set precedence) for the conditional tests.


if ($theother && ($this || $that)) { do some stuff }
4

You are replacing the $result of the outer while in the do loop. Replace $result in the do loop with $result2 and it should work.



```php

$query  = "SELECT * FROM books";
$result = mysql_query($query)
      or die('mysql error ' . mysql_error() . ' in query ' . $query);
  while ($row = mysql_fetch_array($result))
  {
    $splitkeywords1 = $row['keywords'];
    $splitkeywords2 = explode(',',$splitkeywords1);
    $keyindex = -1;

    foreach($splitkeywords2 as $newtab)
    {
        $newtab = $splitkeywords2[$keyindex];
        echo $newtab;
        $query  = "SELECT * FROM $newtab";
        $result2 = mysql_query($query) // $result2 instead of $result
          or 
        tablecreation($newtab);
    }
  };

Or did you mean to overwrite $results ? I’m not entirely clear as to what the code should do.
Oh, I also replaced do {} while {} with a foreach()

As for the (), , and {}

  • () are used in funtion calls functionB[/B] and loop constructs foreach($var as $value)
  • are used for array indices $array[0] and substring $string[0]
  • {} are used for function and loop bodies: function foo($arg1,$arg2) { doSomething(); }, while($a < 10) {doSomething();}