WordPress: custom post type column, create, link and sort by

wordpress_add_custom_post_type_column.php

<?php
function manage_mypostype_custom_column( $column, $post_id ) {
    global $post;

    switch( $column ) {
        case 'category':

            $terms = get_the_terms( $post_id,  'mypostype-category' );
            if($terms[0]){
                $theCategory = $terms[0]->name;
                $termID = $terms[0]->term_id;
                echo "<a href='/wp-admin/term.php?taxonomy=mypostype-category&tag_ID=".$termID."&post_type=mypostype'>".$theCategory."</a>";
            }
            break;

        /* Just break out of the switch statement for everything else. */
        default :
            break;
    }
}
add_action( 'manage_mypostype_posts_custom_column', 'manage_mypostype_custom_column', 10, 2 );

function manage_mypostype_columns( $columns ) {

    return [
        'cb' => '<input type="checkbox" />',
        'title' => 'Title',
        'category' => 'Category',
        'date' => 'Date'
    ];

}
add_filter( 'manage_mypostype_posts_columns', 'manage_mypostype_columns' );

// Make these columns sortable
function sortable_edit_mypostype_columns($columns) {
    $columns['category'] = 'mypostype-category';
    return $columns;
}
add_filter( "manage_edit-mypostype_sortable_columns", "sortable_edit_mypostype_columns" );