condition within a loop??

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September 6th, 2000, 01:57 AM

ranesh_w

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Join Date: Aug 2000

Location: Colombo, Western, Sri Lanka

Posts: 41

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categories table info :
id: unique auto increment
parent_id: all master categories =0
sub categories = id of its master category
name : name of category

The script I've written is supposed to each master category in the table followed immediately by any sub-categories it may have. If a particular master category does not have any subcategories it should fetch the next master category.

My script works fine up to the point where the table contains a few subcategories before the next master category. At this point it lists out the subcategory (which has already been listed earlier within a master category) again assuming that it is a master category.

All I need if an if or while statement in my script. I've tried different variations, but nothing worked.

Here's the script :

<html>
<body>
<?php
mysql_connect(.....);
mysql_select_db(...);
$result = mysql("select * from categories where id!=0");
$num = mysql_numrows($result);
$i = 0;

while($i < $num) {

echo "<p>";

echo mysql_result($result,$i,"name");

echo "<p>";

$pid=mysql_result($result,$i,"id");

$subcategory=mysql_query("select name from categories where parent_id=$pid");

$num2=mysql_numrows($subcategory);

$j=0;

while ($j<$num2){

echo "<p>";

print (" ");

echo mysql_result($subcategory,$j,"name");

$j++;}

$i++;}

?>

</body>
</html>

This is what I have in my mind.

Immediately after the first 'while' there should be something like this :

$parent=mysql_result($result,$i,"parent_id");

if ($parent=0) :

and just before $i++:}

endif;

That's the idea. But it doesn't work. I get a blank screen.

Somebody please help me

Thanks a lot to anyone who will be able to help me out.

September 6th, 2000, 09:40 AM

rod k

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Join Date: Jul 1999

Location: Niagara Falls (On the wrong side of the gorge)

Posts: 3,237

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Reputation Power: 13

You are selecting all categories in your first query, so sub-categories will be included. Then you select sub-categories again by the parent id. Naturally, they'll show up twice.

Modify your first query to exclude non-toplevel categories.

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