unlimited sub-categories

[UnknownPlayer]

How can i make unlimited sub categories when i have this mysql fields: id, name, parent

 

 

$query = "SELECT * FROM cats";
$result = mysql_query($query);
while ($var = mysql_fetch_array($result)) {
  echo $var['name'];
  // now i need here some code for sub cats, but sub cat in subcat 
}

 

Can someone help me?

[btherl]

The right approach depends on what you are doing.  Are you trying to display the entire category tree in a single page?  If so you will need recursion.  A good start would be to write a function called "get_subcats($id)" which recursively calls itself to get subcats of subcats.

[UnknownPlayer]

Yes i wonna to display like a tree, can you give me example?

[btherl]

The code is simpler if you use multiple queries.  First make a function:

 

get_subcats($parent) {
  $query = "SELECT * FROM cats WHERE parent = '" . mysql_real_escape_string($parent) . "'";
  $result = mysql_query($query) or die("Error in $query: " . mysql_error());
  while ($var = mysql_fetch_array($result)) {
    echo $var['name'];
    get_subcats($var['id']);
  }  
}

 

I'm assuming your parent column is an id number.  Also the exact code depends on what value your top level nodes have for the parent column - is this null, 0 or some other value?

[whisperer19]

Check this out

 

http://www.phpfreaks.com/forums/index.php?topic=205633.0

 

it works fine. Just use the code of the last post

[btherl]

FYI the code posted by whisperer19 only allows one level of subcategories

[whisperer19]

FYI the code posted by whisperer19 only allows one level of subcategories

 

No, I've tested the code and it supports unlimited subcategories

[btherl]

It needs a bit more than what's in that thread to support unlimited subcategories.  The code there has no recursion, which is the key idea needed to make this work.

[whisperer19]

Last week I was looking for a function that will return a tree structure of categories and unlimited subcategories, from a table with just 3 basic fields: id, category & parent_category.

This is the most simple code (very clever) that I found and it works fine. Test it and you'll see that you can have unlimited subcategories.

[btherl]

I'm not sure we're talking about the same thing here.  I'm talking about a tree with unlimited depth, such as DMOZ.