Convert – Import A Drupal 6 Based Website To WordPress v2.7

Drupal 6 To WordPress 2.7

Recently we had to convert a Drupal 6 based website Themestand over to WordPress v2.7 due to the amount of Database resources Drupal 6 was consuming on each page load, even for a pretty simple site we found Drupal very heavy on resources especially when users were logged in as the page cache is then inactive. This left us with a simple choice of do we try to further optimize a Drupal system thats already been heavily optimized or do we switch to a less MYSQL hungry system that we can modify to perform the same functions? Our chosen solution was to convert the entire site’s content from Drupal 6 to WordPress 2.7.

Their are various reasons as to why you may wish to convert a Drupal 6 based website to WordPress, maybe you want to convert a blog originally built upon Drupal to WordPress, it could be that you want a system thats a little easier to code themes for, or maybe you just prefer WordPress over Drupal, for us the reason was simply server load due to the amount of MYSQL queries drupal was consuming for what is not really a complicated website.

After looking around the web reading various articles on the subject of Drupal to WordPress conversion most of which are unfortunatley now outdated and with some trial and error we eventually figured out the MYSQL code and process needed to acheive a basic Drupal 6 to WordPress 2.7 site migration. In this article we will describe the steps needed to import your Drupal 6 website into a WordPress v2.7 install.

The actual database conversion from Drupal 6 to WordPress should take around 40 – 60 minutes, then you will have theme wordpress etc and check all the posts, categories and tags so all in all it may take you a few hours to complete this process in full.

Checklist

  1. Make sure you have 40 – 60 minutes that will be free from distractions, wife, kids, phone, dog, twitter etc.
  2. Do not under any circumstances perform this task on a live website, install WAMP or similar on your PC to use as a development server.
  3. Completely backup your Drupal 6 website files and database included.
  4. Have a fresh install of WordPress v2.7 installed and running, backup this also as it easier to just upload the DB file if you mess up during conversion instead of starting again from the beginning.
  5. Grab a coffee, tea, beer or personal weapon of choice and begin.

Step One

Install a fresh copy of WordPress v2.7 and it’s database to your development server our created database name was titled “tempdb” title yours the same if you do not want to edit any of our supplied SQL queries, this is the install we will be importing Drupal 6 into so check that wordpress is fully functional before continuing. Goto phpMyadmin and backup this database, also take note of which table have been installed by WordPress these tables always begin with wp_ as you will need to recognize these for later. Below is a list of the basic WordPress install tables within a fresh install.

  • wp_comments
  • wp_links
  • wp_options
  • wp_postmeta
  • wp_posts
  • wp_ratings
  • wp_terms
  • wp_term_relationships
  • wp_term_taxonomy
  • wp_usermeta
  • wp_users

Now grab the SQL file backup of you Drupal 6 based website, goto phpMyadmin or similar and upload that database into the same database where you installed WordPress. This is very important as for conversion/import we need both the Druapl6 and WordPress 2.7 databases to be combined to begin with.

Once that step is complete we can begin to run the SQL queries with phpMyadmin that will import the data from your Drupal 6 database into the WordPress 2.7 database.

Drupal 6 To WordPress SQL Queries

This part of the process is carried out using phpMyadmin as we will be running SQL queries to import data from the Drupal 6 database into the WordPress v2.7 database.

phpmyadmin-sql

Goto the page above in your database as this is where we will be pasting the SQL queries to that are listed below.

First off we need to clean out any data that may reside within certain WordPress tables, copy, past and run the query below in phpMyadmin to do this.

IMPORTANT: the “tempdb.” that is within the code if your database is not named “tempdb” you will need to change all instances of  “tempdb” to the name of your actual database. So for example if your database is called “wordpress” it would look like this “wordpress.wp_comments;” etc.

Clean WordPress Before Import

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TRUNCATE TABLE tempdb.wp_comments;
TRUNCATE TABLE tempdb.wp_links;
TRUNCATE TABLE tempdb.wp_postmeta;
TRUNCATE TABLE tempdb.wp_posts;
TRUNCATE TABLE tempdb.wp_term_relationships;
TRUNCATE TABLE tempdb.wp_term_taxonomy;
TRUNCATE TABLE tempdb.wp_terms;

Import Taxonomy Terms

This next query will import taxonomy terms.

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INSERT INTO tempdb.wp_terms (term_id, `name`, slug, term_group)
SELECT
 d.tid, d.name, REPLACE(LOWER(d.name), ' ', '-'), 0
FROM tempdb.term_data d
INNER JOIN tempdb.term_hierarchy h
 USING(tid)
;
 
INSERT INTO tempdb.wp_term_taxonomy (term_id, taxonomy, description, parent)
SELECT
 d.tid `term_id`,
 'category' `taxonomy`,
 d.description `description`,
 h.parent `parent`
FROM tempdb.term_data d
INNER JOIN tempdb.term_hierarchy h
 USING(tid)
;

Import Post Content

This query will import Drupal post content to WordPress.

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INSERT INTO
    tempdb.wp_posts (id, post_date, post_content, post_title,
    post_excerpt, post_name, post_modified)
SELECT DISTINCT
    n.nid, FROM_UNIXTIME(created), body, n.title,
    teaser,
    REPLACE(REPLACE(REPLACE(REPLACE(LOWER(n.title),' ', '-'),'.', '-'),',', '-'),'+', '-'),
    FROM_UNIXTIME(changed)
FROM tempdb.node n, tempdb.node_revisions r
WHERE n.vid = r.vid

Post and Category Relations Query

This query relates imported posts to their categories.

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INSERT INTO tempdb.wp_term_relationships (object_id, term_taxonomy_id)
SELECT nid, tid FROM tempdb.term_node;

Category Count Updating

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UPDATE wp_term_taxonomy tt
SET `count` = (
 SELECT COUNT(tr.object_id)
 FROM wp_term_relationships tr
 WHERE tr.term_taxonomy_id = tt.term_taxonomy_id
);

Comments Query keeping unapproved comments hidden

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INSERT INTO tempdb.wp_comments (comment_post_ID, comment_date, comment_content, comment_parent, comment_author, comment_author_email, comment_author_url, comment_approved)
SELECT nid, FROM_UNIXTIME(timestamp), comment, thread, name, mail, homepage, status FROM tempdb.comments;

Update comments count on wp_posts table query

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UPDATE `wp_posts` SET `comment_count` = (SELECT COUNT(`comment_post_id`) FROM `wp_comments` WHERE `wp_posts`.`id` = `wp_comments`.`comment_post_id`);

Fix breaks in post content

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UPDATE tempdb.wp_posts SET post_content = REPLACE(post_content, '', '');

Fix images in post content

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UPDATE tempdb.wp_posts SET post_content = REPLACE(post_content, '"/sites/default/files/', '"/wp-content/uploads/');

If all went smoothly all your Drupal 6 content should have been imported over to WordPress, you can now delete the Drupal database tables from your database leaving the wp_ tables intact.

Now instead of having a possible 100+ sql tables with Drupal and it’s Modules you have a small and compact eleven or so with WordPress that includes exactly the same content as was contained within your Drupal site.

Final Steps

Upload the content/images from your /sites/default/files folder that you backed up with Drupal to your WordPress /wp-content/uploads folder otherwise images for imported posts will not work.

The final steps of the procedure is to browse through your content checking, categories, tags etc looking for any errors misplaced posts. Fix any you come across then you can theme your new site up and release it to the world.

I hope this may help some by cutting out the many hours of research into this procedure that we needed to do before our conversion and any questions, feedback, suggestions, improvements you have after testing this method please leave a comment.

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Article Details

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Author: on May 20th, 2009

Category: Drupal, Planet Drupal, Wordpress

Tags: , , ,

  1. Ares says:

    Thanks for the great tutorial… it saved me countless hours having to go through tons of other outdated pages. Best of luck to you going forward.. Kudos!

  2. George says:

    Very interesting… thanks.

  3. Rufus says:

    Drupal is going to have a hard time keeping up with the new features of WordPress 2.8…look at this article.

  4. Duran says:

    What hardware were you running your site on, that was suffering from the load? What kind of user counts were you seeing that was causing all of this load?

    Had you looked at any of the optimization procedures that exist for drupal to better improve your sites performance?
    http://drupal.org/project/memcache
    http://drupal.org/node/2601

    I’m curious what your hardware and traffic was when you were having these problems.

    Thanks.

  5. Dan says:

    Thanks for the great article! – I’ve used this and it worked great – however I would like to be able to transfer users and tags accross too – could you add this?

    I’ve also noticed the images in the drupal site I’m converting are in a separate module and not the actual post – I’m wondering if there will be any way to transfer the images across automatically in this case, as I have 900+ posts to do!

    Cheers

    Dan

  6. Daniel says:

    Freaking beautiful. This worked perfectly the first time with no messing around. Thank you!

  7. Lincoln says:

    @Dan the only way you may be able to acheive this is to write a custom query for the particular module which holds the images. You would have to query the bd dield that holds the images and then import that query to the WP database.

    @Daniel Happy it worked for you and hopefully saved you some time and hassle 😉

  8. John conrad says:

    Very useful information. Thanks for this. You got a great blog .I will be interested in more similar topics.I’m very interested in CMS and all its related subjects.

  9. Ata says:

    Dear Sir!! Thanks for such a great work. How can I import my users?

  10. Anja Shau says:

    Thanks for the article.
    Have yet to try it out, but it is the best I have found until now.

    We need to change because some of our contributers have trouble to post content. They complain it is not easy to use, the editor is not working 100%, images are a bit complicated to add.

    Also updating the site with all the modules is time consuming, because the updates are not on auto.

    WordPress has a better user back end right now and a lot of people know how to use it.

    Drupal still is a very good system, very flexible with all its modules, but Drupal 6 admin section is not easy for the average user. Hope Drupal will catch up to WordPress in that respect soon.

    I feel sad that we need to do migrate to WordPress, since I was the one who recommended Drupal, but for the sake of our contributers the change needs to be done.