Optimizes WordPress database behind the scenes by executing an OPTIMIZE TABLE statement on all MySQL tables, 'daily' or 'hourly' as a WordPress Cron. More information @ https://www.saotn.org/optimize-wordpress-mysql-tables-cron/

wp-database-tables-optimizer.php

<?php
/**
 * Plugin Name: Saotn Database Table Optimizer
 * Plugin URI: https://www.saotn.org
 * Description: Optimizes WordPress database behind the scenes by executing an OPTIMIZE TABLE statement on all MySQL tables, 'daily' or 'hourly'. Please <a rel="nofollow" target="_blank" href="https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&amp;hosted_button_id=4EFPSXA623NZA" title="donate to Sysadmins of the North">donate $2.50 USD</a> through PayPal to support me in my research time and hosting costs.
 * Version: 1.0.2
 * Author: Jan Reilink
 * Author URI: https://www.saotn.org
 * License: GPLv2
 */

class Saotn_Db_Optimize_Tables_Cron {
  public static function load() {
    add_action( 'init', array( __CLASS__, 'schedule_events' ) );
  }

  /**
   * Schedule cron events, runs during init.
   */
  public static function schedule_events() {
    if ( ! wp_next_scheduled( 'saotn_db_optimize_tables_cron' ) )
      // wp_schedule_event( time(), 'daily', 'saotn_db_optimize_tables_cron' );
      wp_schedule_event( time(), 'hourly', 'saotn_db_optimize_tables_cron' );
      add_action( 'saotn_db_optimize_tables_cron', array( __CLASS__, 'optimize_tables' ) );
  }

  public static function optimize_tables() {
    global $wpdb;
    $bDebug = TRUE;
    $tables = $wpdb->get_col( "SHOW TABLES" );
    foreach ( $tables as $table ) {
      if ( $wpdb->query( "OPTIMIZE TABLE $table" ) !== FALSE ) {
        if ( $bDebug ) {
          error_log( "Saotn_Db_Optimizer ran successfully on $table" );
        }
      }
    }
  }
}

Saotn_Db_Optimize_Tables_Cron::load();