Hello all...I'm looking for some suggestions on a good method for creating nested categories. What I would like to do is store the category info in a database with 3 columns:

---------------------------------------------------------
| category_id | parent_id | category_name |
---------------------------------------------------------

That's easy enough...where I'm having trouble is retrieving this data in a way that makes it easy to place into a drop down list on a web page like this: 

Category 1
 - Subcategory 1
   - Subsubcategory1
     - Subsubsubcategory1
     - Subsubsubcategory2
 - Subcategory 2
   - Subsubcategory1
   - Subsubcategory2
   - Subsubcategory3

This is what I have so far (not the entire script...just the relevant parts): 

my ($category_list) = getCategories();

### Trying to figure out how to loop through $category_list 
for (my $search_total=0; $search_total<=$#$category_list; $search_tota
+l++) {

#    Do something with these:    
#    $category_list->[$search_total]->{category_id}
#    $category_list->[$search_total]->{parent_id}
#    $category_list->[$search_total]->{category_name}

}

### Used to do a single select to grab all categories
sub getCategories {
    my ($results_data) = [];
    my $row = 0;
    
       my $sql = qq~SELECT category_id, parent_id, category_name FROM 
+ss_catalog_categories~;
    my $sth = $dbh->prepare($sql);
    $sth->execute;
    while (my @results = $sth->fetchrow_array()) {
        $results_data->[$row]->{category_id} = $results[0];
        $results_data->[$row]->{parent_id} = $results[1];
        $results_data->[$row++]->{category_name} = $results[2];
        
    }
    $sth->finish;    
    
    return ($results_data);    
    
}

[download]

Any suggestions on doing this correctly would be wonderful. Thanks.

In reply to Nested Categories by spaceout

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