Order Posts by Alphabetical for Each Letter

Question

I need to order my posts by alphabetical for each letter. I mean:

When people enter to www.xxx.com/a, they will just see posts by starting A.

ABC XYZ

ADE KLM

ARE UYZ

When people enter to www.xxx.com/b, they will just see posts by starting B.

BCK OIO

BHJ PEP

I hope you will understand what I want. I have founded this code:

    <?php
$last_char = '';
$args=array(
  'orderby' => 'title',
  'order' => 'ASC',
  'posts_per_page'=>-1,
  'caller_get_posts'=>1
);
$my_query = new WP_Query($args);
if( $my_query->have_posts() ) {
  echo 'Alphabetic index of all ' . count($my_query->posts) . ' posts';
  while ($my_query->have_posts()) : $my_query->the_post();
    $this_char = strtoupper(substr($post->post_title,0,1));
    if ($this_char != $last_char) {
      $last_char = $this_char;
      echo '<h2>'.$last_char.'</h2>';
    } ?>
    <p><a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to <?php the_title_attribute(); ?>"><?php the_title(); ?></a></p>
    <?php
  endwhile;
} //if ($my_query)
wp_reset_query();  // Restore global post data stomped by the_post().
?>

However, this code lists all posts by alphabetical in one page. As I said before, I just want same thing but for one letter which I specify.

Thank you for helping me.

Answer 1

This is what I find for this question. Two codes I found were coded by MichaelH from wordpress.org. Even he won't probably see this post, I want to thank him.

Now, I just need to sort these posts from specified one category. If anyone knows how to sort them with specified category, please help me. Thanks.

   <?php
    //get all post IDs for posts beginning with cap B, in title order,
    //display posts
    $first_char = 'B';

    $postids=$wpdb->get_col($wpdb->prepare("
    SELECT      ID
    FROM        $wpdb->posts
    WHERE       SUBSTR($wpdb->posts.post_title,1,1) = %s
    ORDER BY    $wpdb->posts.post_title",$first_char)); 

    if ($postids) {
    $args=array(
      'post__in' => $postids,
      'post_type' => 'post',
      'post_status' => 'publish',
      'posts_per_page' => -1,
      'caller_get_posts'=> 1
    );
    $my_query = null;
    $my_query = new WP_Query($args);
    if( $my_query->have_posts() ) {
     echo 'List of Posts Titles beginning with the letter '. $first_char;
      while ($my_query->have_posts()) : $my_query->the_post(); ?>
        <p><a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to <?php the_title_attribute(); ?>"><?php the_title(); ?></a></p>
        <?php
      endwhile;
    }
    wp_reset_query();  // Restore global post data stomped by the_post().
    }
    ?>

Answer 2

This code uses the last letter in the URL to search for all posts that starts with that specific letter. So mysite.com/a will return all posts starting with the letter "a". For this to work properly, I would suggest creating a category for each letter of the alphabet.

Here is a combination several pieces of code.

Firstly, you need to get the current URL of the page you are on. Thanks to Stephen Harris, the following code will just do that

$current_url = home_url(add_query_arg(array(),$wp->request));

Secondly, now that you have the current URL, you need to strip away everything before the last/ and just keep the letter. Thanks to DisgruntledGoat

$id = substr( $current_url, strrpos( $current_url, '/' )+1 );

Ok, now that you have the last letter, you need to return that back into a query to get all the posts that start with the letter. Again, thanks go to 21zna9

$request = $id; 
    $results = $wpdb->get_results(
        "
            SELECT * FROM $wpdb->posts
            WHERE post_title LIKE '$request%'
            AND post_type = 'post'
            AND post_status = 'publish'; 
        "
    ); 

Now, putting everything into one working query.

<ul class="posts">
<?php 
    global $wpdb, $wp; 
    $current_url = home_url(add_query_arg(array(),$wp->request));
    $id = substr( $current_url, strrpos( $current_url, '/' )+1 );
    $request = $id; 
    $results = $wpdb->get_results(
        "
            SELECT * FROM $wpdb->posts
            WHERE post_title LIKE '$request%'
            AND post_type = 'post'
            AND post_status = 'publish'; 
        "
    ); 

    if ( $results ) {
        foreach ( $results as $post ) {
            setup_postdata ( $post ); ?> 

                <li>
                    <?php get_template_part( 'content', get_post_format() ); ?>
                </li>

            <?php 
        }
    } else { ?>

    <div class="alert">No posts found for this particular letter.</div>

<?php } ?>
</ul>

You will just need to modify the output of the loop to suite your needs. The code above will give you a general idea of what to do