Rewrite Rules to custom template

Question

At the moment I have the following:

a custom template: my_custom_template.php where the function below is called.

<?php $uni_data = get_uni_data() ?>

a page: www.website.com/my_page which is using the custom_template

functions in functions.php:

function get_uni_data() {
   $segments = explode('/', trim(parse_url($_SERVER['REQUEST_URI'], PHP_URL_PATH), '/'));

   $uni_data = [];

    // for www.example.com/user/account you will get 'user'
   global $wpdb;
   $uni_data = $wpdb->get_row("SELECT * FROM university_table WHERE name LIKE 'Clemson'", ARRAY_A );


   return $uni_data;

I want to change the query statment value after LIKE to be whatever the end of the url parse is i.e when someone goes to www.website.com/university/Clemson or www.website.com/university/Duke

the query value is Clemson or Duke.

So, I would like to have add a rule to where whenever the user goes to the url: www.website.com/university/NAME

the template is called and filled in using get_uni_data with NAME as the query value.

Do I need to have a page like my_page above to handle this? Or can i just use the template? How would the rewrite rule look to just the template and not with a specific page in mind?

EDIT 1

I have added the following function (as per similar question) but the page does not exist.

add_action('init', function() {
    $url_path = trim(parse_url(add_query_arg(array()), PHP_URL_PATH), '/');
    $templatename = 'university';
    $pos = strpos($url_path, $templatename);

    if ( $pos != false) {
        $load = locate_template('my_custom_template.php', true);
        return $load;
    }

}) ;

EDIT 2

I will try now how this question is answered where the rewrite rule will look like:

add_rewrite_rule(
        'university/([^/]+)/?$',
        'index.php?pagename=university&uniname=$matches[1],
        'top'
    );

and the queryvars is:

    $query_vars[] = 'uniname';

and change the get_uni_data function to have an argument (uniname) which will be put after the LIKE statement.

But I really do not understand how add_action is working or add_filter so I am not sure if these will work.

EDIT 3

So I have implemenetd the following in my functions.php file:

add_action('init', 'wp_university_full_rewrite');
function wp_university_full_rewrite() {
    add_rewrite_rule(
        'university/[^/]*)/?$',
        'index.php?pagename=university&uni_name=$matches[1]',
        'top');
}
add_filter('query_vars', 'wp_university_full_query_vars');
function wp_university_full_query_vars( $query_vars ) {
    $query_vars[] = 'uni_name';
    return $query_vars  ;
}
function get_uni_data_with_query( $uni_name_query ) {

    $uni_data = [];

    global $wpdb;
    $uni_data = $wpdb->get_row("SELECT * FROM university_table WHERE name LIKE ".$uni_name_query, ARRAY_A );


    return $uni_data;

}

and in my template I have added:

<?php $uni_name_pull = get_query_var('uni_name') ?>
<?php $uni_data = get_uni_data_with_query($uni_name_pull) ?>

but now I get the following error:

Warning: preg_match(): Compilation failed: unmatched parentheses at offset 17 in /home4/ratemyp9/public_html/wp-includes/class-wp.php on line 224

Answer 1

Found the solution:

functions.php:

add_action('init', 'wp_university_full_rewrite');
function wp_university_full_rewrite() {
    add_rewrite_rule(
        'university/([^/]*)/?$',
        'index.php?pagename=university&uni_name=$matches[1]',
        'top');
}
add_filter('query_vars', 'wp_university_full_query_vars');
function wp_university_full_query_vars( $query_vars ) {
    $query_vars[] = 'uni_name';
    return $query_vars  ;
}

function get_data_with_query( $name_query ) {

    $data = [];

    global $wpdb;
    $data = $wpdb->get_row("SELECT * FROM table WHERE name = '".$name_query."'", ARRAY_A );


    return $data;

}

custom_template.php:

<?php $name_pull = get_query_var('uni_name') ?>
<?php $uni_data2 = get_data_with_query($name_pull) ?>

and there is a page with slug 'university' that has its template as my_custom_template.

I know this is a very crude way of doing things, so now it's time to wrap everything in if statements and error pages!!