joining two tables

Original - php Code <? function display($show_cat) { categories($categories); } function categories($categories) { $sql = "select * from categories"; $result = mysql_query($sql); $category_id = $row["category_id"]; while($row = mysql_fetch_array($result)) { printf("<p><a href="?category_id=%s">%s</a>n<br>", $row["category_id"], $row["category"]); } } function display_cat($show_list) { cat_list($cat_list); } function cat_list($cat_list) { $sql = "select distinct * from companies,categories where companies.category_id = categories.category_id and categories.category_id = '$category_id'"; $result = mysql_query($sql); while($row = mysql_fetch_array($result)) { printf("<p><a href="?company_id=%s">%s</a>n%sn<br>%sn<br>", $row["company_id"], $row["name"], $row["category_id"], $row["services"]); } } if(isset($category_id)): head("Category"); display_cat($show_list); else: head("Listing"); display($show_cat); endif; ?>

 
<?
function display($show_cat) {
        categories($categories);
    }
 
function categories($categories) {
        $sql = "select * from categories";
        $result = mysql_query($sql);
        $category_id = $row["category_id"];
        while($row = mysql_fetch_array($result)) {
        printf("<p><a href="?category_id=%s">%s</a>n<br>", $row["category_id"], $row["category"]);
        }
    }
 
function display_cat($show_list) {
        cat_list($cat_list);
    }
 
function cat_list($cat_list) {
        $sql = "select distinct * from companies,categories where companies.category_id = categories.category_id and categories.category_id = '$category_id'";
        $result = mysql_query($sql);
        while($row = mysql_fetch_array($result)) {
        printf("<p><a href="?company_id=%s">%s</a>n%sn<br>%sn<br>", $row["company_id"], $row["name"], $row["category_id"], $row["services"]);
        }
    }
    
 
if(isset($category_id)):
    head("Category");
    display_cat($show_list);
else:
    head("Listing");
    display($show_cat);
 
endif;
?>