Can I index the meta_key in the postmeta table?

This is one of two ‘Power Tweaks’ which are a feature of WP-Optimize Premium. This power tweak works by ensuring the meta_key column in the WordPress postmeta table can be indexed.

The tweak specifically targets the meta_key column in the WordPress postmeta table, ensuring it can be indexed effectively. By default, this column appears indexed but is actually restricted due to the utf8mb4 character encoding, which limits column indexing to 191 characters. Since the meta_key column is 256 characters long, it exceeds this limit and cannot be indexed.

This power tweak adjusts the column size down to 191 characters, making it indexable. This change significantly speeds up query performance by allowing faster data retrieval, thereby optimizing your WordPress site’s database operations.