return array Select and join statements for address table.
	 */
	private function join_address_table_order_query( $address_type, $order_table_alias, $address_table_alias ) {
		global $wpdb;
		$address_table    = $this::get_addresses_table_name();
		$column_props_map = 'billing' === $address_type ? $this->billing_address_column_mapping : $this->shipping_address_column_mapping;
		$clauses          = $this->generate_select_and_join_clauses( $order_table_alias, $address_table, $address_table_alias, $column_props_map );
		// phpcs:disable WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- $clauses['join'] and $address_table_alias are hardcoded.
		$clauses['join'] = $wpdb->prepare(
			"{$clauses['join']} AND $address_table_alias.address_type = %s",
			$address_type
		);

		// phpcs:enable
		return array(
			'select' => $clauses['select'],
			'join'   => $clauses['join'],
		);
	}

	/**
	 * Helper method to join order operational data table.
	 *
	 * @param string $order_table_alias Alias to use for order table.
	 * @param string $operational_table_alias Alias to use for operational data table.
	 *
	 * @return array Select and join queries for operational data table.
	 */
	private function join_operational_data_table_to_order_query( $order_table_alias, $operational_table_alias ) {
		$operational_data_table = $this::get_operational_data_table_name();

		return $this->generate_select_and_join_clauses(
			$order_table_alias,
			$operational_data_table,
			$operational_table_alias,
			$this->operational_data_column_mapping
		);
	}

	/**
	 * Helper method to generate join and select clauses.
	 *
	 * @param string  $order_table_alias Alias for order table.
	 * @param string  $table Table to join.
	 * @param string  $table_alias Alias for table to join.
	 * @param array[] $column_props_map Column to prop map for table to join.
	 *
	 * @return array Select and join queries.
	 */
	private function generate_select_and_join_clauses( $order_table_alias, $table, $table_alias, $column_props_map ) {
		// Add aliases to column names so they will be unique when fetching.
		$select_clause = $this->generate_select_clause_for_props( $table_alias, $column_props_map );
		$join_clause   = "$table $table_alias ON $table_alias.order_id = $order_table_alias.id";

		return array(
			'select' => $select_clause,
			'join'   => $join_clause,
		);
	}

	/**
	 * Helper method to generate select clause for props.
	 *
	 * @param string  $table_alias Alias for table.
	 * @param array[] $props Props to column mapping for table.
	 *
	 * @return string Select clause.
	 */
	private function generate_select_clause_for_props( $table_alias, $props ) {
		$select_clauses = array();
		foreach ( $props as $column_name => $prop_details ) {
			$select_clauses[] = isset( $prop_details['name'] ) ? "$table_alias.$column_name as {$prop_details['name']}" : "$table_alias.$column_name as {$table_alias}_$column_name";
		}

		return implode( ', ', $select_clauses );
	}

	/**
	 * Persists order changes to the database.
	 *
	 * @param \WC_Abstract_Order $order            The order.
	 * @param bool               $force_all_fields Force saving all fields to DB and just changed.
	 *
	 * @throws \Exception If order data is not valid.
	 *
	 * @since 6.8.0
	 */
	protected function persist_order_to_db( &$order, bool $force_all_fields = false ) {
		$context   = ( 0 === absint( $order->get_id() ) ) ? 'create' : 'update';
		$data_sync = wc_get_container()->get( DataSynchronizer::class );

		if ( 'create' === $context ) {
			$post_id = wp_insert_post(
				array(
					'post_type'   => $data_sync->data_sync_is_enabled() ? $order->get_type() : $data_sync::PLACEHOLDER_ORDER_POST_TYPE,
					'post_status' => 'draft',
				)
			);

			if ( ! $post_id ) {
				throw new \Exception( __( 'Could not create order in posts table.', 'woocommerce' ) );
			}

			$order->set_id( $post_id );
		}

		$only_changes = ! $force_all_fields && 'update' === $context;
		// Figure out what needs to be updated in the database.
		$db_updates = $this->get_db_rows_for_order( $order, $context, $only_changes );

		// Persist changes.
		foreach ( $db_updates as $update ) {
			// Make sure 'data' and 'format' entries match before passing to $wpdb.
			ksort( $update['data'] );
			ksort( $update['format'] );

			$result = $this->database_util->insert_on_duplicate_key_update(
				$update['table'],
				$update['data'],
				array_values( $update['format'] )
			);

			if ( false === $result ) {
				// translators: %s is a table name.
				throw new \Exception( sprintf( __( 'Could not persist order to database table "%s".', 'woocommerce' ), $update['table'] ) );
			}
		}

		$changes = $order->get_changes();
		$this->update_address_index_meta( $order, $changes );
	}

	/**
	 * Generates an array of rows with all the details required to insert or update an order in the database.
	 *
	 * @param \WC_Abstract_Order $order The order.
	 * @param string             $context The context: 'create' or 'update'.
	 * @param boolean            $only_changes Whether to consider only changes in the order for generating the rows.
	 *
	 * @return array
	 * @throws \Exception When invalid data is found for the given context.
	 *
	 * @since 6.8.0
	 */
	protected function get_db_rows_for_order( \WC_Abstract_Order $order, string $context = 'create', bool $only_changes = false ): array {
		$result = array();

		$row = $this->get_db_row_from_order( $order, $this->order_column_mapping, $only_changes );
		if ( 'create' === $context && ! $row ) {
			throw new \Exception( 'No data for new record.' ); // This shouldn't occur.
		}

		if ( $row ) {
			$result[] = array(
				'table'  => self::get_orders_table_name(),
				'data'   => array_merge( $row['data'], array( 'id' => $order->get_id() ) ),
				'format' => array_merge( $row['format'], array( 'id' => '%d' ) ),
			);
		}

		// wc_order_operational_data.
		$row = $this->get_db_row_from_order( $order, $this->operational_data_column_mapping, $only_changes );
		if ( $row ) {
			$result[] = array(
				'table'  => self::get_operational_data_table_name(),
				'data'   => array_merge( $row['data'], array( 'order_id' => $order->get_id() ) ),
				'format' => array_merge( $row['format'], array( 'order_id' => '%d' ) ),
			);
		}

		// wc_order_addresses.
		foreach ( array( 'billing', 'shipping' ) as $address_type ) {
			$row = $this->get_db_row_from_order( $order, $this->{$address_type . '_address_column_mapping'}, $only_changes );

			if ( $row ) {
				$result[] = array(
					'table'  => self::get_addresses_table_name(),
					'data'   => array_merge(
						$row['data'],
						array(
							'order_id'     => $order->get_id(),
							'address_type' => $address_type,
						)
					),
					'format' => array_merge(
						$row['format'],
						array(
							'order_id'     => '%d',
							'address_type' => '%s',
						)
					),
				);
			}
		}

		/**
		 * Allow third parties to include rows that need to be inserted/updated in custom tables when persisting an order.
		 *
		 * @since 6.8.0
		 *
		 * @param array      Array of rows to be inserted/updated when persisting an order. Each entry should be an array with
		 *                   keys 'table', 'data' (the row), 'format' (row format), 'where' and 'where_format'.
		 * @param \WC_Order  The order object.
		 * @param string     The context of the operation: 'create' or 'update'.
		 */
		$ext_rows = apply_filters( 'woocommerce_orders_table_datastore_extra_db_rows_for_order', array(), $order, $context );

		return array_merge( $result, $ext_rows );
	}

	/**
	 * Produces an array with keys 'row' and 'format' that can be passed to `$wpdb->update()` as the `$data` and
	 * `$format` parameters. Values are taken from the order changes array and properly formatted for inclusion in the
	 * database.
	 *
	 * @param \WC_Abstract_Order $order          Order.
	 * @param array              $column_mapping Table column mapping.
	 * @param bool               $only_changes   Whether to consider only changes in the order object or all fields.
	 * @return array
	 *
	 * @since 6.8.0
	 */
	protected function get_db_row_from_order( $order, $column_mapping, $only_changes = false ) {
		$changes = $only_changes ? $order->get_changes() : array_merge( $order->get_data(), $order->get_changes() );

		$changes['type'] = $order->get_type();

		// Make sure 'status' is correct.
		if ( array_key_exists( 'status', $column_mapping ) ) {
			$changes['status'] = $this->get_post_status( $order );
		}

		$row        = array();
		$row_format = array();

		foreach ( $column_mapping as $column => $details ) {
			if ( ! isset( $details['name'] ) || ! array_key_exists( $details['name'], $changes ) ) {
				continue;
			}

			$row[ $column ]        = $this->database_util->format_object_value_for_db( $changes[ $details['name'] ], $details['type'] );
			$row_format[ $column ] = $this->database_util->get_wpdb_format_for_type( $details['type'] );
		}

		if ( ! $row ) {
			return false;
		}

		return array(
			'data'   => $row,
			'format' => $row_format,
		);
	}


	//phpcs:disable Squiz.Commenting, Generic.Commenting

	/**
	 * Method to delete an order from the database.
	 *
	 * @param \WC_Abstract_Order $order Order object.
	 * @param array              $args Array of args to pass to the delete method.
	 *
	 * @return void
	 */
	public function delete( &$order, $args = array() ) {
		$order_id = $order->get_id();

		if ( ! $order_id ) {
			return;
		}

		if ( ! empty( $args['force_delete'] ) ) {

			/**
			 * Fires immediately before an order is deleted from the database.
			 *
			 * @since 7.1.0
			 *
			 * @param int      $order_id ID of the order about to be deleted.
			 * @param WC_Order $order    Instance of the order that is about to be deleted.
			 */
			do_action( 'woocommerce_before_delete_order', $order_id, $order );

			$this->delete_order_data_from_custom_order_tables( $order_id );
			$order->set_id( 0 );

			// If this datastore method is called while the posts table is authoritative, refrain from deleting post data.
			if ( $order->get_data_store()->get_current_class_name() !== self::class ) {
				return;
			}

			// Delete the associated post, which in turn deletes order items, etc. through {@see WC_Post_Data}.
			// Once we stop creating posts for orders, we should do the cleanup here instead.
			wp_delete_post( $order_id );

			do_action( 'woocommerce_delete_order', $order_id ); // phpcs:ignore WooCommerce.Commenting.CommentHooks.MissingHookComment
		} else {
			/**
			 * Fires immediately before an order is trashed.
			 *
			 * @since 7.1.0
			 *
			 * @param int      $order_id ID of the order about to be deleted.
			 * @param WC_Order $order    Instance of the order that is about to be deleted.
			 */
			do_action( 'woocommerce_before_trash_order', $order_id, $order );

			$this->trash_order( $order );

			do_action( 'woocommerce_trash_order', $order_id ); // phpcs:ignore WooCommerce.Commenting.CommentHooks.MissingHookComment
		}
	}

	/**
	 * Trashes an order.
	 *
	 * @param WC_Order $order The order object
	 * @return void
	 */
	public function trash_order( $order ) {
		global $wpdb;

		if ( 'trash' === $order->get_status( 'edit' ) ) {
			return;
		}

		$trash_metadata = array(
			'_wp_trash_meta_status' => 'wc-' . $order->get_status( 'edit' ),
			'_wp_trash_meta_time'   => time(),
		);

		foreach ( $trash_metadata as $meta_key => $meta_value ) {
			$this->add_meta(
				$order,
				(object) array(
					'key'   => $meta_key,
					'value' => $meta_value,
				)
			);
		}

		$wpdb->update(
			self::get_orders_table_name(),
			array(
				'status'           => 'trash',
				'date_updated_gmt' => current_time( 'Y-m-d H:i:s', true ),
			),
			array( 'id' => $order->get_id() ),
			array( '%s', '%s' ),
			array( '%d' )
		);

		$order->set_status( 'trash' );

		$data_synchronizer = wc_get_container()->get( DataSynchronizer::class );
		if ( $data_synchronizer->data_sync_is_enabled() ) {
			wp_trash_post( $order->get_id() );
		}
	}

	/**
	 * Attempts to restore the specified order back to its original status (after having been trashed).
	 *
	 * @param WC_Order $order The order to be untrashed.
	 *
	 * @return bool If the operation was successful.
	 */
	public function untrash_order( WC_Order $order ): bool {
		$id     = $order->get_id();
		$status = $order->get_status();

		if ( 'trash' !== $status ) {
			wc_get_logger()->warning(
				sprintf(
					/* translators: 1: order ID, 2: order status */
					__( 'Order %1$d cannot be restored from the trash: it has already been restored to status "%2$s".', 'woocommerce' ),
					$id,
					$status
				)
			);
			return false;
		}

		$previous_status           = $order->get_meta( '_wp_trash_meta_status' );
		$valid_statuses            = wc_get_order_statuses();
		$previous_state_is_invalid = ! array_key_exists( $previous_status, $valid_statuses );
		$pending_is_valid_status   = array_key_exists( 'wc-pending', $valid_statuses );

		if ( $previous_state_is_invalid && $pending_is_valid_status ) {
			// If the previous status is no longer valid, let's try to restore it to "pending" instead.
			wc_get_logger()->warning(
				sprintf(
					/* translators: 1: order ID, 2: order status */
					__( 'The previous status of order %1$d ("%2$s") is invalid. It has been restored to "pending" status instead.', 'woocommerce' ),
					$id,
					$previous_status
				)
			);

			$previous_status = 'pending';
		} elseif ( $previous_state_is_invalid ) {
			// If we cannot restore to pending, we should probably stand back and let the merchant intervene some other way.
			wc_get_logger()->warning(
				sprintf(
					/* translators: 1: order ID, 2: order status */
					__( 'The previous status of order %1$d ("%2$s") is invalid. It could not be restored.', 'woocommerce' ),
					$id,
					$previous_status
				)
			);

			return false;
		}

		/**
		 * Fires before an order is restored from the trash.
		 *
		 * @since 7.2.0
		 *
		 * @param int    $order_id        Order ID.
		 * @param string $previous_status The status of the order before it was trashed.
		 */
		do_action( 'woocommerce_untrash_order', $order->get_id(), $previous_status );

		$order->set_status( $previous_status );
		$order->save();

		// Was the status successfully restored? Let's clean up the meta and indicate success...
		if ( 'wc-' . $order->get_status() === $previous_status ) {
			$order->delete_meta_data( '_wp_trash_meta_status' );
			$order->delete_meta_data( '_wp_trash_meta_time' );
			$order->delete_meta_data( '_wp_trash_meta_comments_status' );
			$order->save_meta_data();

			$data_synchronizer = wc_get_container()->get( DataSynchronizer::class );
			if ( $data_synchronizer->data_sync_is_enabled() ) {
				//The previous $order->save() will have forced a sync to the posts table,
				//this implies that the post status is not "trash" anymore, and thus
				//wp_untrash_post would do nothing.
				wp_update_post(
					array(
						'ID'          => $id,
						'post_status' => 'trash',
					)
				);

				wp_untrash_post( $id );
			}

			return true;
		}

		// ...Or log a warning and bail.
		wc_get_logger()->warning(
			sprintf(
				/* translators: 1: order ID, 2: order status */
				__( 'Something went wrong when trying to restore order %d from the trash. It could not be restored.', 'woocommerce' ),
				$id
			)
		);

		return false;
	}


	/**
	 * Deletes order data from custom order tables.
	 *
	 * @param int $order_id The order ID.
	 * @return void
	 */
	public function delete_order_data_from_custom_order_tables( $order_id ) {
		global $wpdb;

		// Delete COT-specific data.
		foreach ( $this->get_all_table_names() as $table ) {
			$wpdb->delete(
				$table,
				( self::get_orders_table_name() === $table )
					? array( 'id' => $order_id )
					: array( 'order_id' => $order_id ),
				array( '%d' )
			);
		}
	}

	/**
	 * Method to create an order in the database.
	 *
	 * @param \WC_Order $order Order object.
	 */
	public function create( &$order ) {
		if ( '' === $order->get_order_key() ) {
			$order->set_order_key( wc_generate_order_key() );
		}

		$this->persist_save( $order );

		/**
		 * Fires when a new order is created.
		 *
		 * @since 2.7.0
		 *
		 * @param int       Order ID.
		 * @param \WC_Order Order object.
		 */
		do_action( 'woocommerce_new_order', $order->get_id(), $order );
	}

	/**
	 * Helper method responsible for persisting new data to order table.
	 *
	 * This should not contain and specific meta or actions, so that it can be used other order types safely.
	 *
	 * @param \WC_Order $order Order object.
	 *
	 * @return void
	 *
	 * @throws \Exception When unable to save data.
	 */
	protected function persist_save( &$order, bool $force_all_fields = false, $backfill = true ) {
		$order->set_version( Constants::get_constant( 'WC_VERSION' ) );
		$order->set_currency( $order->get_currency() ? $order->get_currency() : get_woocommerce_currency() );

		if ( ! $order->get_date_created( 'edit' ) ) {
			$order->set_date_created( time() );
		}

		$this->update_order_meta( $order );

		$this->persist_order_to_db( $order, $force_all_fields );

		$order->save_meta_data();
		$order->apply_changes();

		if ( $backfill ) {
			$this->maybe_backfill_post_record( $order );
		}
		$this->clear_caches( $order );
	}

	/**
	 * Method to update an order in the database.
	 *
	 * @param \WC_Order $order
	 */
	public function update( &$order ) {
		// Before updating, ensure date paid is set if missing.
		if (
			! $order->get_date_paid( 'edit' )
			&& version_compare( $order->get_version( 'edit' ), '3.0', '<' )
			&& $order->has_status( apply_filters( 'woocommerce_payment_complete_order_status', $order->needs_processing() ? 'processing' : 'completed', $order->get_id(), $order ) ) // phpcs:ignore WooCommerce.Commenting.CommentHooks.MissingHookComment
		) {
			$order->set_date_paid( $order->get_date_created( 'edit' ) );
		}

		if ( null === $order->get_date_created( 'edit' ) ) {
			$order->set_date_created( time() );
		}

		$order->set_version( Constants::get_constant( 'WC_VERSION' ) );

		// Fetch changes.
		$changes = $order->get_changes();
		$this->persist_updates( $order );

		// Update download permissions if necessary.
		if ( array_key_exists( 'billing_email', $changes ) || array_key_exists( 'customer_id', $changes ) ) {
			$data_store = \WC_Data_Store::load( 'customer-download' );
			$data_store->update_user_by_order_id( $order->get_id(), $order->get_customer_id(), $order->get_billing_email() );
		}

		// Mark user account as active.
		if ( array_key_exists( 'customer_id', $changes ) ) {
			wc_update_user_last_active( $order->get_customer_id() );
		}

		$order->apply_changes();
		$this->clear_caches( $order );

		do_action( 'woocommerce_update_order', $order->get_id(), $order ); // phpcs:ignore WooCommerce.Commenting.CommentHooks.MissingHookComment
	}

	/**
	 * Proxy to udpating order meta. Here for backward compatibility reasons.
	 *
	 * @param \WC_Order $order Order object.
	 *
	 * @return void
	 */
	protected function update_post_meta( &$order ) {
		$this->update_order_meta( $order );
	}

	/**
	 * Helper method that is responsible for persisting order updates to the database.
	 *
	 * This is expected to be reused by other order types, and should not contain any specific metadata updates or actions.
	 *
	 * @param \WC_Order $order Order object.
	 *
	 * @return array $changes Array of changes.
	 *
	 * @throws \Exception When unable to persist order.
	 */
	protected function persist_updates( &$order, $backfill = true ) {
		// Fetch changes.
		$changes = $order->get_changes();

		if ( ! isset( $changes['date_modified'] ) ) {
			$order->set_date_modified( time() );
		}

		if ( $backfill ) {
			$this->maybe_backfill_post_record( $order );
		}

		$this->persist_order_to_db( $order );
		$order->save_meta_data();

		return $changes;
	}

	/**
	 * Helper function to decide whether to backfill post record.
	 *
	 * @param \WC_Abstract_Order $order Order object.
	 *
	 * @return void
	 */
	private function maybe_backfill_post_record( $order ) {
		$data_sync = wc_get_container()->get( DataSynchronizer::class );
		if ( $data_sync->data_sync_is_enabled() ) {
			$this->backfill_post_record( $order );
		}
	}

	/**
	 * Helper method that updates post meta based on an order object.
	 * Mostly used for backwards compatibility purposes in this datastore.
	 *
	 * @param \WC_Order $order Order object.
	 *
	 * @since 7.0.0
	 */
	public function update_order_meta( &$order ) {
		$changes = $order->get_changes();
		$this->update_address_index_meta( $order, $changes );
	}

	/**
	 * Helper function to update billing and shipping address metadata.
	 * @param \WC_Abstract_Order $order Order Object
	 * @param array              $changes Array of changes.
	 *
	 * @return void
	 */
	private function update_address_index_meta( $order, $changes ) {
		// If address changed, store concatenated version to make searches faster.
		foreach ( array( 'billing', 'shipping' ) as $address_type ) {
			if ( isset( $changes[ $address_type ] ) ) {
				$order->update_meta_data( "_{$address_type}_address_index", implode( ' ', $order->get_address( $address_type ) ) );
			}
		}
	}

	/**
	 * Return array of coupon_code => meta_key for coupon which have usage limit and have tentative keys.
	 * Pass $coupon_id if key for only one of the coupon is needed.
	 *
	 * @param WC_Order $order     Order object.
	 * @param int      $coupon_id If passed, will return held key for that coupon.
	 *
	 * @return array|string Key value pair for coupon code and meta key name. If $coupon_id is passed, returns meta_key for only that coupon.
	 */
	public function get_coupon_held_keys( $order, $coupon_id = null ) {
		$held_keys = $order->get_meta( '_coupon_held_keys' );
		if ( $coupon_id ) {
			return isset( $held_keys[ $coupon_id ] ) ? $held_keys[ $coupon_id ] : null;
		}
		return $held_keys;
	}

	/**
	 * Return array of coupon_code => meta_key for coupon which have usage limit per customer and have tentative keys.
	 *
	 * @param WC_Order $order Order object.
	 * @param int      $coupon_id If passed, will return held key for that coupon.
	 *
	 * @return mixed
	 */
	public function get_coupon_held_keys_for_users( $order, $coupon_id = null ) {
		$held_keys_for_user = $order->get_meta( '_coupon_held_keys_for_users' );
		if ( $coupon_id ) {
			return isset( $held_keys_for_user[ $coupon_id ] ) ? $held_keys_for_user[ $coupon_id ] : null;
		}
		return $held_keys_for_user;
	}

	/**
	 * Add/Update list of meta keys that are currently being used by this order to hold a coupon.
	 * This is used to figure out what all meta entries we should delete when order is cancelled/completed.
	 *
	 * @param WC_Order $order              Order object.
	 * @param array    $held_keys          Array of coupon_code => meta_key.
	 * @param array    $held_keys_for_user Array of coupon_code => meta_key for held coupon for user.
	 *
	 * @return mixed
	 */
	public function set_coupon_held_keys( $order, $held_keys, $held_keys_for_user ) {
		if ( is_array( $held_keys ) && 0 < count( $held_keys ) ) {
			$order->update_meta_data( '_coupon_held_keys', $held_keys );
		}
		if ( is_array( $held_keys_for_user ) && 0 < count( $held_keys_for_user ) ) {
			$order->update_meta_data( '_coupon_held_keys_for_users', $held_keys_for_user );
		}
	}

	/**
	 * Release all coupons held by this order.
	 *
	 * @param WC_Order $order Current order object.
	 * @param bool     $save  Whether to delete keys from DB right away. Could be useful to pass `false` if you are building a bulk request.
	 */
	public function release_held_coupons( $order, $save = true ) {
		$coupon_held_keys = $this->get_coupon_held_keys( $order );
		if ( is_array( $coupon_held_keys ) ) {
			foreach ( $coupon_held_keys as $coupon_id => $meta_key ) {
				$coupon = new \WC_Coupon( $coupon_id );
				$coupon->delete_meta_data( $meta_key );
				$coupon->save_meta_data();
			}
		}
		$order->delete_meta_data( '_coupon_held_keys' );

		$coupon_held_keys_for_users = $this->get_coupon_held_keys_for_users( $order );
		if ( is_array( $coupon_held_keys_for_users ) ) {
			foreach ( $coupon_held_keys_for_users as $coupon_id => $meta_key ) {
				$coupon = new \WC_Coupon( $coupon_id );
				$coupon->delete_meta_data( $meta_key );
				$coupon->save_meta_data();
			}
		}
		$order->delete_meta_data( '_coupon_held_keys_for_users' );

		if ( $save ) {
			$order->save_meta_data();
		}

	}

	public function query( $query_vars ) {
		if ( ! isset( $query_vars['paginate'] ) || ! $query_vars['paginate'] ) {
			$query_vars['no_found_rows'] = true;
		}

		if ( isset( $query_vars['anonymized'] ) ) {
			$query_vars['meta_query'] = $query_vars['meta_query'] ?? array(); // phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_query

			if ( $query_vars['anonymized'] ) {
				$query_vars['meta_query'][] = array(
					'key'   => '_anonymized',
					'value' => 'yes',
				);
			} else {
				$query_vars['meta_query'][] = array(
					'key'     => '_anonymized',
					'compare' => 'NOT EXISTS',
				);
			}
		}

		try {
			$query = new OrdersTableQuery( $query_vars );
		} catch ( \Exception $e ) {
			$query = (object) array(
				'orders'        => array(),
				'found_orders'  => 0,
				'max_num_pages' => 0,
			);
		}

		if ( isset( $query_vars['return'] ) && 'ids' === $query_vars['return'] ) {
			$orders = $query->orders;
		} else {
			$orders = WC()->order_factory->get_orders( $query->orders );
		}

		if ( isset( $query_vars['paginate'] ) && $query_vars['paginate'] ) {
			return (object) array(
				'orders'        => $orders,
				'total'         => $query->found_orders,
				'max_num_pages' => $query->max_num_pages,
			);
		}

		return $orders;
	}

	public function get_order_item_type( $order, $order_item_id ) {
		return 'line_item';
	}

	//phpcs:enable Squiz.Commenting, Generic.Commenting

	/**
	 * Get the SQL needed to create all the tables needed for the custom orders table feature.
	 *
	 * @return string
	 */
	public function get_database_schema() {
		global $wpdb;

		$collate = $wpdb->has_cap( 'collation' ) ? $wpdb->get_charset_collate() : '';

		$orders_table_name           = $this->get_orders_table_name();
		$addresses_table_name        = $this->get_addresses_table_name();
		$operational_data_table_name = $this->get_operational_data_table_name();
		$meta_table                  = $this->get_meta_table_name();

		$sql = "
CREATE TABLE $orders_table_name (
	id bigint(20) unsigned,
	status varchar(20) null,
	currency varchar(10) null,
	type varchar(20) null,
	tax_amount decimal(26,8) null,
	total_amount decimal(26,8) null,
	customer_id bigint(20) unsigned null,
	billing_email varchar(320) null,
	date_created_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),
	KEY billing_email (billing_email),
	KEY type_status (type, status),
	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),
	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),
	UNIQUE 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, meta_value(100)),
	KEY order_id_meta_key_meta_value (order_id, meta_key, meta_value(100))
) $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 $meta (containing at least ->id).
	 */
	public function delete_meta( &$object, $meta ) {
		return $this->data_store_meta->delete_meta( $object, $meta );
	}

	/**
	 * Add new piece of meta.
	 *
	 * @param  WC_Data  $object WC_Data object.
	 * @param  stdClass $meta (containing ->key and ->value).
	 * @return int meta ID
	 */
	public function add_meta( &$object, $meta ) {
		return $this->data_store_meta->add_meta( $object, $meta );
	}

	/**
	 * Update meta.
	 *
	 * @param  WC_Data  $object WC_Data object.
	 * @param  stdClass $meta (containing ->id, ->key and ->value).
	 */
	public function update_meta( &$object, $meta ) {
		return $this->data_store_meta->update_meta( $object, $meta );
	}
}