How to Copy Value from One meta Field to Another one in WordPress

Introduction

In WordPress development, there often arises a need to copy values from one custom field (meta field) to another. This might be necessary during a rebranding of site components or when transitioning to new plugins that use different keys to store information. In this article, we will discuss how to automate the process of copying data between meta fields using an SQL query through phpMyAdmin.

The Problem

Suppose you have a meta field old_videos where video links are stored, and you want to transfer all these data into a new meta field new_videos. This task may emerge as a result of changes in the site structure or the integration of new functionality that requires a different meta field name.

The Solution

To address this issue, we can use an SQL query to update values in the WordPress database. First and foremost, it's crucial to ensure that you have a backup of the database to prevent data loss in case of an error.

Here is the SQL query that updates the values in the oldvideos meta field based on the values from new_videos:

UPDATE wp_postmeta AS dest
JOIN (
  SELECT post_id, meta_value
  FROM wp_postmeta
  WHERE meta_key = 'old_videos'
) AS src ON dest.post_id = src.post_id
SET dest.meta_value = src.meta_value
WHERE dest.meta_key = 'new_videos';

How to Use This Query

1. Log into phpMyAdmin OR use plugin WP phpMyAdmin.
2. Select the database of your WordPress site.
3. Go to the SQL tab.
4. Paste the above query into the SQL query field.
5. Execute the query by clicking the "Go" or "Execute" button.

Conclusion

Using an SQL query to copy values between meta fields in WordPress is an efficient way to manage data on your site. This method allows for quick adaptation of the site's content to changing requirements and ensures high precision in data handling. Always make backups before conducting such operations to avoid potential data loss.