How to Optimize Your WordPress Database for Better Speed and Performance

David

David Nguyen

January 19, 2025

WordPress Database for Better Speed and Performance

Why Is Database Optimization Important for WordPress?

Your WordPress database contains everything: posts, pages, comments, plugin settings, and media files. The more you update and manage your content, the more data WordPress adds to the database. Not all of it is useful, though.

  • Slower Queries: As your database grows, queries to retrieve data become slower.
  • Increased Storage: Unnecessary data consumes storage, which may have a performance impact.
  • Potential Errors: Unused or even outdated data builds up, giving rise to some errors and issues.

Cleaning the database regularly through optimization will see your website sped up and performing efficiently, making it free of potential problems on the way down the line.

Steps to Optimize Your WordPress Database

1. Delete Post Revisions

WordPress keeps versions of your posts and pages by default every time you make any changes. The great feature in this is change tracking, but it does crowd up your database with redundant information.

How to Clean Post Revisions:

  1. Clean post revisions through the WP-Optimize plugin, which lets you delete all of them in one go
  2. Or, if you are skilled with SQL, you can apply this query on your database for deletion: DELETE FROM wp_posts WHERE post_type = “revision”;

2. Delete Spam Comments and Unapproved Comments

Spam comments can easily accumulate in your WordPress database and really slow it down. WordPress does not delete spam comments automatically, so they can sit there forever.

How to Delete Spam Comments:

  1. Go to your WordPress dashboard under Comments and filter for spam comments.
  2. Use the Akismet plugin to automatically block spam comments in the future.
  3. You can also manually delete old or unapproved comments.

3. Clean Up Unused Tags and Categories

You will likely collect unused tags and categories on your WordPress website over time. These unused terms can inflate your database and slow down query performance.

How to Clean Up Tags and Categories:

  1. Open Posts > Tags or Posts > Categories in your WordPress dashboard.
  2. Review and delete any unused tags or categories that are not actively in use.

    4. Delete Transients and Expired Data

    Transients are temporary data retained in the WordPress database. Plugins frequently depend on them to cache information, however, expired and unused transients build up and slow down your site.

    How to Clean Expired Transients:

    1. Add a plugin like Transient Cleaner that cleans up expired transients.
    2. Or by manually using the SQL query below: DELETE FROM wp_options WHERE option_name LIKE (‘%_transient_%’);

      5. Clean up your Database Tables

      WordPress stores all of your data in database tables. Over time, these tables can become fragmented and need optimization. Optimizing database tables helps to reclaim unused space and improve query performance.

      How to Optimize Tables:

      1. Use the WP-Optimize plugin to automatically optimize your database tables.
      2. Alternatively, you can run this SQL query: OPTIMIZE TABLE wp_posts, wp_comments, wp_options;

        6. Disable Unnecessary Post Revisions (Optional)

        WordPress by default saves an infinite number of post revisions. While useful for tracking changes, they can cause a bloated database. You can limit or completely disable post revisions.

        How to Limit Post Revisions:

        1. Add the following line to your wp-config.php file to limit the number of revisions WordPress keeps: define( ‘WP_POST_REVISIONS’, 5 ); // Limits to 5 revisions per post
        2. Alternatively, set it to false to disable revisions completely: define(‘WP_POST_REVISIONS’, false );

          7. Database Optimization Plugins

          For those who are not technically savvy, the easiest way to optimize a WordPress database is by using a plugin. Several plugins can do this for you, thus eliminating manual queries and complicated settings.

          Recommended Database Optimization Plugins:

          1. WP-Optimize: It is an all-in-one database cleaning and optimization plugin.
          2. Advanced Database Cleaner: Cleans and optimizes your database by clearing up unnecessary data, like revisions, drafts, and expired transients.
          3. WP-Sweep: Sweeps the database for unnecessary data

          How to Backup Your Database Before Optimization

          In case you make a change and something happens during the process, it’s highly important that you have created a backup beforehand. You can make a database backup of your blog with the following procedures:

          1. Using a Plugin: Plugins such as UpdraftPlus or BackupBuddy make it easy to back up your database.
          2. Manual Backup via phpMyAdmin: If you prefer to do it manually, you can export your database from phpMyAdmin.

          Best Practices for Ongoing Database Optimization

          1. Schedule Regular Optimizations: Make database optimization a part of your regular maintenance routine. Many plugins allow you to set automatic cleanup schedules.
          2. Limit Revisions: As discussed above, limiting post revisions will prevent your database from growing too large.
          3. Monitor Database Growth: Keep up to date with regard to your database size and structure; if it’s growing too fast, investigate.

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