Question

I am having trouble with writing a simple(!) PHP function to return an array of values under the following scenario.

I have a database table that simply lists parent and child categories (e.g. menu, sub menu, sub sub menu) in two fields ‘parent_id’ and ‘category_id’. I want to tunnel down through the table to pull out all the bottom category_ids – i.e. those that are not listed as ‘parents’ to any others but are children (or grand children or great grand children) of the category_id input to the function

I have a function a bit like this (it runs on osCommerce based code so the sql query stuff looks odd

function tep_get_bottom_categories( $categories_id) {
    $bottom_categories_query = tep_db_query("select categories_id from categories where parent_id = '" . $categories_id . "'");
    while ($bottom_categories = tep_db_fetch_array($bottom_categories_query)) {
        if(XXXXXXXXXXXXX)//<---- tried lots of stuff here
            {$results[]=$bottom_categories['categories_id'];}
        else
            {tep_get_bottom_categories( $bottom_categories['categories_id']);
        }
    }//end while loop 
}// end function

If I input a value to the function that has children then it will produce those in an array of $bottom_categories and then do the same all the way down to the final bottom categories – however these are not singled out and placed in the $results array as I need something to go where XXXXXXXXXXXXXX is but that is evading me mightily.

I’m assuming that I need to label each loop of the function in some way but I fail to see how – thanks – Graeme

Answer 1

I would always run the else case and check if the query has any results. If it has no children you are ready and insert it into the list; otherwise same as before.

Example code:

function tep_get_bottom_categories( $categories_id) {
  $bottom_categories_query = tep_db_query("select categories_id from categories where parent_id = '" . $categories_id . "'");

  if( /* check num_rows == 0 */ {
    {$results[]=$categories_id;}
  } else {
    while ($bottom_categories = tep_db_fetch_array($bottom_categories_query)) {
      {tep_get_bottom_categories( $bottom_categories['categories_id']);}
    }//end while loop 
  }
}// end function