query_vars in plugin when using custom permalinks

When pretty permalinks are enabled, the query var is category_name:

$wp_query->query_vars['category_name'];

or use get_queried_object:

$this_category = get_queried_object();
echo $this_category->term_id;
echo $this_category->name;
echo $this_category->slug;
// etc..

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)