Page not found return false
Supposing that example.com is a site running Drupal, what Drupal does when you try to access  example.com/exhibition/speacial_feature is:


Verify exhibition/speacial_feature is a path alias
Verify there is a menu that uses exhibition/speacial_feature as path
Verify a module define a menu callback for exhibition/speacial_feature


If none of the conditions is verified, then Drupal returns a 404 error.

In your case, as you want to execute code when a path is entered, you need to create a module that defines a menu callback.

function mymodule_menu() {
  $items = array();

  $items['mymodule/%/%'] = array(
    'page callback' =&gt; 'mymodule_abc_view',
    'page arguments' =&gt; array(1, 2),
  );

  return $items;
}

function mymodule_page_view($first, $second) {
  // Execute the query, and show the result.
} 


The code for hook_menu() I shown is the minimum required; see hook_menu() for more information.

As also noted from Berdir, you don't concatenate input given from a user to obtain the query to execute, as that causes SQL injection. You need to use query parameters, which are supported in any Drupal version. Also, with static queries, the name of the database tables are surrounded by { and }.