This begs the question, how do we make our custom columns sortable, too? If we add custom meta attributes to posts or create custom post types, sometimes it’s nice to display these fields in the admin tables. There are plenty of posts out there that describe how do that. So, let’s focus on how to make these columns sortable.

A new filter was introduced called manage_{$screen->id}_sortable_columns. This works just like the existing filter that we use to add our own column headings to the table. Let’s imagine we created a meta field for our posts called ‘my_author’. (Remember, it’s a good idea to prepend your meta columns with a custom prefix. As an example we’ll use “my_” but you should probably use something more specific in your code. We usually use “stereo_”.

      // add this code to wherever you define your custom post type, usually within a plugin or your theme's functions.php file.
      // you should be familiar with this filter from earlier versions of wp...
      add_filter("manage_edit-".$post_type."_columns", 'my_edit_columns'));
      // this is the new filter which expects an array in the format of id => data
      add_filter("manage_edit-".$post_type."_sortable_columns", 'my_sortable_columns');

      // ...
        function my_sortable_columns($columns)
  	{
  	  $custom = array(
            // meta column id => sortby value used in query
  	    'my_author'    => 'my_author',
  	  );

  	  return wp_parse_args($custom, $columns);
  	}

If you have it set up correctly, when you view your list of posts in the admin area, the columns defined in your my_sortable_columns function should be active links, and clicking on them toggle sort order.

http://wordpress.stackexchange.com/questions/5750/custom-field-meta-populated-by-dropdown-of-existing-posts

1. Edit your wp-config.php so it works on various environments. I do this like so:

// ** MySQL settings - You can get this info from your web host ** //
switch ($_SERVER['SERVER_NAME']) {
  case 'mysite.local': // local dev environment
    // ** MySQL settings - You can get this info from your web host ** //
    /** The name of the database for WordPress */
    define('DB_NAME', 'mylocal_db');
    /** MySQL database username */
    define('DB_USER', 'root');
    /** MySQL database password */
    define('DB_PASSWORD', '');
    /** MySQL hostname */
    define('DB_HOST', 'localhost');
    break;
  default:
    /** The name of the database for WordPress */
    define('DB_NAME', 'yourlive_db');
    /** MySQL database username */
    define('DB_USER', 'yourlive_dbuser');
    /** MySQL database password */
    define('DB_PASSWORD', 'yourlive_pw');
    /** MySQL hostname */
    define('DB_HOST', 'localhost');
    break;
}

That will let you use the same wp-config.php file on either server.

2. I dump my local database. I do this using a little shell script that will search the mysql dump for my local url and replace it with the live one. I put the following in a file called dbdump.sh:

#!/bin/bash
 
# dump database
mysqldump -u root mylocal_db > mylocal_db_dump.sql
 
# search inside the mylocal_db_dump.sql file for 'mysite.local' and replace with 'thelivesite.com'
perl -pi -e 's/mysite.local/thelivesite.com/g' mylocal_db_dump.sql

Then I can run this script with the command “./dbdump.sh” anytime I want to export my local database to an sql file to import on the live site.

3. I use rsync to sync my local version of the site up to the server. Alternatively, you could use FTP to upload the entire local site, but it’s harder to keep things in sync this way. If you want to use SSH, I put the following into a file named something like “upload.sh” and put it in my blog folder.

#!/bin/bash
GO=$1
: ${GO:=""}
 
if [ "$GO" = "go" ]
then
  ARGS="-avc"
else
  ARGS="-avcn"
fi
 
rsync $ARGS --stats --progress --exclude-from=rsync_exclude.txt -e 'ssh' . username@yourserver.com:/home/path/to/your/public_html

Basically what this does is execute the “rsync” command with a few arguments. It will look at the files in the current directory on your machine and compare them with the files on the server. If you execute this script with a “go” parameter, it will actually perform the copy; otherwise it does a dry-run to show you what changes would occur. I put a list of a few files to ignore while syncing in “rsync_exclude.txt”. I ignore any hidden files like .DS_Store, my custom upload shell script which we just created, and temporary files and uploads.

Here is what mine usually contains:

.DS_Store
.htaccess
upload.sh
dbdump.sh
rsync_exclude.txt
/wp-content/cache/*
/wp-content/uploads/*

You can then run the upload.sh script by executing the command like this:

./upload.sh

And if it looks ok, you actually perform the sync with:

./upload.sh go

4. Now we have all our files synced up… we just need to update the database. You can either either use something like phpMyAdmin to upload your “mylocal_db_dump.sql” file, or if you have SSH access you can execute it using your live mysql user:

mysql -u yourlive_dbuser -p mylocal_db_dump.sql > yourlive_db

This may seem like a lot of steps, but if you are rapidly developing your site and need to re-upload to a staging server frequently, this ends up saving a ton of time. Once you have the files in place, updating the live site is a simple matter of running these commands:

./dbdump.sh
./upload.sh

and then insert your SQL file into your live database, either through the command line or phpMyAdmin.

Now that I have these files I just copy them into any wordpress site I’m working on and I’m ready to upload as often as I want and it only takes a few seconds. I hope you find some use out of them, too.

If you want to download a bundle of the sample files I mention above, you can download a zip archive of them here.

<?php $images = &get_children('post_type=attachment&post_mime_type=image&orderby=menu_order&order=ASC&post_parent='.$post->ID);
    if ($images):
    $image = current($images); $imageData = wp_get_attachment_image_src($image->ID); ?>
    <img src="<?php echo $imageData[0] ?>" alt="<?php the_title() ?>" />
    <?php endif ?>
<!-- image title: $image->post_title, caption: $image->post_excerpt, description: $image->post_content -->

Usually we’d use this just to pull out the first image attachment to a post and use this in a special place in our template. Now that there is built-in post thumbnail support, we wanted to use this feature but also still have the ability to display the selected thumbnail’s caption information. the_post_thumbnail only returns the image tag, so here is our custom filter (inside our template’s functions.php file) that adds our caption:

function monahans_thumbnail_caption($html, $post_id, $post_thumbnail_id, $size, $attr)
{
  $attachment =& get_post($post_thumbnail_id);
 
  // post_title => image title
  // post_excerpt => image caption
  // post_content => image description
 
  if ($attachment->post_excerpt || $attachment->post_content) {
    $html .= '<p class="thumbcaption">';
    if ($attachment->post_excerpt) {
      $html .= '<span class="captitle">'.$attachment->post_excerpt.'</span> ';
    }
    $html .= $attachment->post_content.'</p>';
  }
 
	return $html;
}
 
add_action('post_thumbnail_html', 'monahans_thumbnail_caption', null, 5);

The result of this filter is now anytime we call the_post_thumbnail in our template, the html will come back with our image caption, too.