Change the default language of a Drupal 8.x website

Some weeks before I had to overcame an interesting task. A media webportal in Drupal 8.x with more than 4k articles decided to change the site default language from englush to greek (mainly for SEO reasons but this doesn't matter).

In Drupal 7.x I could say that you need almost magic to do this. But in Drupal 8.x things are somehow easier. In Drupal 8.x all entities that have content (blocks, nodes, users, menu links etc) do have a langcode field by default. This field is the key that allows as to change the site language. Drupal.org suggests to never change the default language, developers try to understand what are the implications of changing the default language but owners need to move forward...

So, here are the steps you need to follow. In this example we change the default language in the mysql database "mydb" from English (en) to Greek (el).

• Create a backup so you don't blame me later!
• Add the new (Greek) language (not the default).
• (Optional) Import translations (po files). May need to change the "translations" folder path.
• (Optional) Install the "redirect" module if not installed already.
• Run one SQL query to get all the tables that include the "langcode" column:

SELECT CONCAT("UPDATE ", TABLE_NAME, " SET langcode = 'el' WHERE langcode = 'en';") AS Query
FROM INFORMATION_SCHEMA.COLUMNS
WHERE COLUMN_NAME = 'langcode' AND TABLE_SCHEMA="mydb"

• Copy the query results in a plain text editor and run them as SQL queries (see the example below).
• Set the Greek lanuage as default using Drupal UI.
• (Optional) Change the UI language selection method (Drupal UI).
• (Optional) Update path aliases to match the new patterns.
• (Optional) Update xmlsitemap and other things that include paths.
• Clear caches

 

FYI here is an example of the query results that need to run second time:

UPDATE block_content SET langcode='el' WHERE langcode='en';
UPDATE block_content__body SET langcode='el' WHERE langcode='en';
UPDATE comment SET langcode='el' WHERE langcode='en';
UPDATE comment__comment_body SET langcode='el' WHERE langcode='en';
UPDATE comment_field_data SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_data_275f010ee6 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_data_2dd43e27b6 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_data_3193803003 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_data_38c21ff70b SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_data_401e137498 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_data_5863e8f98e SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_data_75ceb109c9 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_data_789d23fb7d SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_data_aab97a0971 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_data_abd15f8f5b SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_data_c862b72a26 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_data_d0260352e8 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_data_db292b52bf SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_data_dcf8719bbf SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_revision_275f010ee6 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_revision_2dd43e27b6 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_revision_3193803003 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_revision_38c21ff70b SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_revision_401e137498 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_revision_5863e8f98e SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_revision_75ceb109c9 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_revision_789d23fb7d SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_revision_aab97a0971 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_revision_abd15f8f5b SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_revision_c862b72a26 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_revision_d0260352e8 SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_revision_db292b52bf SET langcode='el' WHERE langcode='en';
UPDATE field_deleted_revision_dcf8719bbf SET langcode='el' WHERE langcode='en';
UPDATE file_managed SET langcode='el' WHERE langcode='en';
UPDATE locale_file SET langcode='el' WHERE langcode='en';
UPDATE media SET langcode='el' WHERE langcode='en';
UPDATE media__field_reusable_image SET langcode='el' WHERE langcode='en';
UPDATE media_field_data SET langcode='el' WHERE langcode='en';
UPDATE media_field_revision SET langcode='el' WHERE langcode='en';
UPDATE media_revision SET langcode='el' WHERE langcode='en';
UPDATE media_revision__field_reusable_image SET langcode='el' WHERE langcode='en';
UPDATE menu_link_content SET langcode='el' WHERE langcode='en';
UPDATE menu_link_content_data SET langcode='el' WHERE langcode='en';
UPDATE node SET langcode='el' WHERE langcode='en';
UPDATE node__body SET langcode='el' WHERE langcode='en';
UPDATE node__comment SET langcode='el' WHERE langcode='en';
UPDATE node__field_event_date SET langcode='el' WHERE langcode='en';
UPDATE node__field_image SET langcode='el' WHERE langcode='en';
UPDATE node__field_image_browser SET langcode='el' WHERE langcode='en';
UPDATE node__field_nodes SET langcode='el' WHERE langcode='en';
UPDATE node__field_reusable_image SET langcode='el' WHERE langcode='en';
UPDATE node__field_tags SET langcode='el' WHERE langcode='en';
UPDATE node__field_video SET langcode='el' WHERE langcode='en';
UPDATE node_access SET langcode='el' WHERE langcode='en';
UPDATE node_field_data SET langcode='el' WHERE langcode='en';
UPDATE node_field_revision SET langcode='el' WHERE langcode='en';
UPDATE node_revision SET langcode='el' WHERE langcode='en';
UPDATE node_revision__body SET langcode='el' WHERE langcode='en';
UPDATE node_revision__comment SET langcode='el' WHERE langcode='en';
UPDATE node_revision__field_event_date SET langcode='el' WHERE langcode='en';
UPDATE node_revision__field_image SET langcode='el' WHERE langcode='en';
UPDATE node_revision__field_image_browser SET langcode='el' WHERE langcode='en';
UPDATE node_revision__field_tags SET langcode='el' WHERE langcode='en';
UPDATE node_revision__field_video SET langcode='el' WHERE langcode='en';
UPDATE search_dataset SET langcode='el' WHERE langcode='en';
UPDATE search_index SET langcode='el' WHERE langcode='en';
UPDATE shortcut SET langcode='el' WHERE langcode='en';
UPDATE shortcut_field_data SET langcode='el' WHERE langcode='en';
UPDATE taxonomy_term__field_variety_attributes SET langcode='el' WHERE langcode='en';
UPDATE taxonomy_term__parent SET langcode='el' WHERE langcode='en';
UPDATE taxonomy_term_data SET langcode='el' WHERE langcode='en';
UPDATE taxonomy_term_field_data SET langcode='el' WHERE langcode='en';
UPDATE url_alias SET langcode='el' WHERE langcode='en';
UPDATE user__roles SET langcode='el' WHERE langcode='en';
UPDATE user__user_picture SET langcode='el' WHERE langcode='en';
UPDATE users SET langcode='el' WHERE langcode='en';
UPDATE users_field_data SET langcode='el' WHERE langcode='en';