how to optimize WordPress database manually

Understanding WordPress Database Performance

WordPress uses MySQL or MariaDB to manage data, including posts, pages, comments, settings, and user information. Over time, databases can become bloated due to excess data, leading to slower website performance.

Step-by-step WordPress Database Optimization

1. Backup Your Database**: Prior to any optimization, create a complete backup to avoid data loss. Use plugins like UpdraftPlus, or tools like phpMyAdmin to export your database.

2. Analyze Database Tables**: Install a database management plugin like WP-DBManager or use phpMyAdmin to check your tables. Look for overhead, which indicates unused space that can be reclaimed.

3. Optimize Database Tables**: In phpMyAdmin, select all tables and choose “Optimize table” from the dropdown menu. This function reorganizes the table and index data, reducing storage overhead.

4. Clean Post Revisions**: WordPress saves every change you make in the posts as revisions, which can accumulate over time. To limit revisions, add define( 'WP_POST_REVISIONS', 4 ); to your wp-config.php file, where ‘4’ is the number of revisions you want to keep.

5. Remove Spam Comments and Unapproved Comments**: Use SQL commands to delete all spam or unapproved comments:

   DELETE FROM wp_comments WHERE comment_approved = 'spam';
   DELETE FROM wp_comments WHERE comment_approved = '0';

6. Delete Unused Tags**: Simplify your database by removing tags with no associated posts:

   DELETE FROM wp_terms wt 
       USING wp_term_taxonomy wtt LEFT JOIN wp_term_relationships wtr on wtr.term_taxonomy_id = wtt.term_taxonomy_id 
       WHERE wtt.taxonomy = 'post_tag' AND wtr.term_taxonomy_id IS NULL;

7. Clear Transients**: Transients are temporary options used to store cached data. Clear expired transients with:

   DELETE FROM wp_options WHERE option_name LIKE ('%_transient_%')

8. Eliminate Orphaned Meta Data**: Remove orphaned postmeta, commentmeta, and usermeta using:

   DELETE pm FROM wp_postmeta pm LEFT JOIN wp_posts wp ON wp.ID = pm.post_id WHERE wp.ID IS NULL;
   DELETE FROM wp_commentmeta WHERE comment_id NOT IN (SELECT comment_id FROM wp_comments);
   DELETE FROM wp_usermeta WHERE user_id NOT IN (SELECT ID FROM wp_users);

9. Purge Old Data**: Delete old, unnecessary data like expired WooCommerce sessions:

   DELETE FROM wp_options WHERE option_name LIKE ('%_wc_session_expire_%') AND option_value < UNIX_TIMESTAMP();

10. Maintain Regular Database Checks**: Schedule regular database optimization every three to six months to maintain performance. Automate this using plugins or cron jobs.

Additional Tips for Enhanced Performance

• Implement Persistent Object Caching: Use Redis or Memcached to cache query results, reducing database load.
• Limit Plugin Bloat: Deactivate and delete any plugins that are not necessary to reduce database calls.
• Use Indexes Efficiently: Properly index essential columns in your database tables to expedite query performance. This is particularly useful for large datasets.
• Analyze Query Performance: Tools like Query Monitor can help identify slow database queries and provide insight into necessary optimizations.

By manually optimizing your WordPress database, you ensure that your website maintains optimal performance and loading speed, enhancing both user experience and SEO effectiveness. Regular maintenance and careful management of database resources are essential practices for any WordPress site owner looking to achieve and sustain high performance.