gmt datetime null,
	date_updated_gmt datetime null,
	parent_order_id bigint(20) unsigned null,
	payment_method varchar(100) null,
	payment_method_title text null,
	transaction_id varchar(100) null,
	ip_address varchar(100) null,
	user_agent text null,
	customer_note text null,
	PRIMARY KEY (id),
	KEY status (status),
	KEY date_created (date_created_gmt),
	KEY customer_id_billing_email (customer_id, billing_email({$composite_customer_id_email_length})),
	KEY billing_email (billing_email($max_index_length)),
	KEY type_status_date (type, status, date_created_gmt),
	KEY parent_order_id (parent_order_id),
	KEY date_updated (date_updated_gmt)
) $collate;
CREATE TABLE $addresses_table_name (
	id bigint(20) unsigned auto_increment primary key,
	order_id bigint(20) unsigned NOT NULL,
	address_type varchar(20) null,
	first_name text null,
	last_name text null,
	company text null,
	address_1 text null,
	address_2 text null,
	city text null,
	state text null,
	postcode text null,
	country text null,
	email varchar(320) null,
	phone varchar(100) null,
	KEY order_id (order_id),
	UNIQUE KEY address_type_order_id (address_type, order_id),
	KEY email (email($max_index_length)),
	KEY phone (phone)
) $collate;
CREATE TABLE $operational_data_table_name (
	id bigint(20) unsigned auto_increment primary key,
	order_id bigint(20) unsigned NULL,
	created_via varchar(100) NULL,
	woocommerce_version varchar(20) NULL,
	prices_include_tax tinyint(1) NULL,
	coupon_usages_are_counted tinyint(1) NULL,
	download_permission_granted tinyint(1) NULL,
	cart_hash varchar(100) NULL,
	new_order_email_sent tinyint(1) NULL,
	order_key varchar(100) NULL,
	order_stock_reduced tinyint(1) NULL,
	date_paid_gmt datetime NULL,
	date_completed_gmt datetime NULL,
	shipping_tax_amount decimal(26,8) NULL,
	shipping_total_amount decimal(26,8) NULL,
	discount_tax_amount decimal(26,8) NULL,
	discount_total_amount decimal(26,8) NULL,
	recorded_sales tinyint(1) NULL,
	UNIQUE KEY order_id (order_id),
	KEY order_key (order_key)
) $collate;
CREATE TABLE $meta_table (
	id bigint(20) unsigned auto_increment primary key,
	order_id bigint(20) unsigned null,
	meta_key varchar(255),
	meta_value text null,
	KEY meta_key_value (meta_key(100), meta_value($composite_meta_value_index_length)),
	KEY order_id_meta_key_meta_value (order_id, meta_key(100), meta_value($composite_meta_value_index_length))
) $collate;
";

		return $sql;
	}

	/**
	 * Returns an array of meta for an object.
	 *
	 * @param  WC_Data $object WC_Data object.
	 * @return array
	 */
	public function read_meta( &$object ) {
		$raw_meta_data = $this->data_store_meta->read_meta( $object );
		return $this->filter_raw_meta_data( $object, $raw_meta_data );
	}

	/**
	 * Deletes meta based on meta ID.
	 *
	 * @param WC_Data   $object WC_Data object.
	 * @param \stdClass $meta (containing at least ->id).
	 *
	 * @return bool
	 */
	public function delete_meta( &$object, $meta ) {
		if ( $this->should_backfill_post_record() && isset( $meta->id ) ) {
			// Let's get the actual meta key before its deleted for backfilling. We cannot delete just by ID because meta IDs are different in HPOS and posts tables.
			$db_meta = $this->data_store_meta->get_metadata_by_id( $meta->id );
			if ( $db_meta ) {
				$meta->key   = $db_meta->meta_key;
				$meta->value = $db_meta->meta_value;
			}
		}

		$delete_meta     = $this->data_store_meta->delete_meta( $object, $meta );
		$changes_applied = $this->after_meta_change( $object, $meta );

		if ( ! $changes_applied && $object instanceof WC_Abstract_Order && $this->should_backfill_post_record() && isset( $meta->key ) ) {
			self::$backfilling_order_ids[] = $object->get_id();
			delete_post_meta( $object->get_id(), $meta->key, $meta->value );
			self::$backfilling_order_ids = array_diff( self::$backfilling_order_ids, array( $object->get_id() ) );
		}

		return $delete_meta;
	}

	/**
	 * Add new piece of meta.
	 *
	 * @param WC_Data   $object WC_Data object.
	 * @param \stdClass $meta (containing ->key and ->value).
	 *
	 * @return int|bool  meta ID or false on failure
	 */
	public function add_meta( &$object, $meta ) {
		$add_meta        = $this->data_store_meta->add_meta( $object, $meta );
		$meta->id        = $add_meta;
		$changes_applied = $this->after_meta_change( $object, $meta );

		if ( ! $changes_applied && $object instanceof WC_Abstract_Order && $this->should_backfill_post_record() ) {
			self::$backfilling_order_ids[] = $object->get_id();
			add_post_meta( $object->get_id(), $meta->key, $meta->value );
			self::$backfilling_order_ids = array_diff( self::$backfilling_order_ids, array( $object->get_id() ) );
		}

		return $add_meta;
	}

	/**
	 * Update meta.
	 *
	 * @param WC_Data   $object WC_Data object.
	 * @param \stdClass $meta (containing ->id, ->key and ->value).
	 *
	 * @return bool The number of rows updated, or false on error.
	 */
	public function update_meta( &$object, $meta ) {
		$update_meta     = $this->data_store_meta->update_meta( $object, $meta );
		$changes_applied = $this->after_meta_change( $object, $meta );

		if ( ! $changes_applied && $object instanceof WC_Abstract_Order && $this->should_backfill_post_record() ) {
			self::$backfilling_order_ids[] = $object->get_id();
			update_post_meta( $object->get_id(), $meta->key, $meta->value );
			self::$backfilling_order_ids = array_diff( self::$backfilling_order_ids, array( $object->get_id() ) );
		}

		return $update_meta;
	}

	/**
	 * Perform after meta change operations, including updating the date_modified field, clearing caches and applying changes.
	 *
	 * @param WC_Abstract_Order $order Order object.
	 * @param \WC_Meta_Data     $meta  Metadata object.
	 *
	 * @return bool True if changes were applied, false otherwise.
	 */
	protected function after_meta_change( &$order, $meta ) {
		method_exists( $meta, 'apply_changes' ) && $meta->apply_changes();

		// Prevent this happening multiple time in same request.
		if ( $this->should_save_after_meta_change( $order, $meta ) ) {
			$order->set_date_modified( current_time( 'mysql' ) );
			$order->save();
			return true;
		} else {
			$order_cache = wc_get_container()->get( OrderCache::class );
			$order_cache->remove( $order->get_id() );
		}

		return false;
	}

	/**
	 * Helper function to check whether the modified date needs to be updated after a meta save.
	 *
	 * This method prevents order->save() call multiple times in the same request after any meta update by checking if:
	 * 1. Order modified date is already the current date, no updates needed in this case.
	 * 2. If there are changes already queued for order object, then we don't need to update the modified date as it will be updated ina subsequent save() call.
	 *
	 * @param WC_Order           $order Order object.
	 * @param \WC_Meta_Data|null $meta  Metadata object.
	 *
	 * @return bool Whether the modified date needs to be updated.
	 */
	private function should_save_after_meta_change( $order, $meta = null ) {
		$current_time      = $this->legacy_proxy->call_function( 'current_time', 'mysql', 1 );
		$current_date_time = new \WC_DateTime( $current_time, new \DateTimeZone( 'GMT' ) );

		return $order->get_date_modified() < $current_date_time && empty( $order->get_changes() ) && ( ! is_object( $meta ) || ! in_array( $meta->key, $this->ephemeral_meta_keys, true ) );
	}
}