您可以使用以下查询获取订单总数。

 $order_totals = apply_filters( \'woocommerce_reports_sales_overview_order_totals\', $wpdb->get_row( "
    SELECT COUNT(posts.ID) AS total_orders FROM {$wpdb->posts} AS posts

    LEFT JOIN {$wpdb->postmeta} AS meta ON posts.ID = meta.post_id
    LEFT JOIN {$wpdb->term_relationships} AS rel ON posts.ID=rel.object_ID
    LEFT JOIN {$wpdb->term_taxonomy} AS tax USING( term_taxonomy_id )
    LEFT JOIN {$wpdb->terms} AS term USING( term_id )

    WHERE   meta.meta_key       = \'_order_total\'
    AND     posts.post_type     = \'shop_order\'
    AND     posts.post_status   = \'publish\'
    AND     tax.taxonomy        = \'shop_order_status\'
    AND     term.slug           IN (\'" . implode( "\',\'", 
apply_filters( \'woocommerce_reports_order_statuses\', 
array( \'completed\', \'processing\', \'on-hold\' ) ) ) . "\')
" ) );

$total_orders_count     = absint( $order_totals->total_orders );