Get today's total orders count for each produc

I'm looking for a code snippet to get total sales of each product for today, so I can use it in my theme functions.php file.

Output should be like this (Total Sales Per Item):

Product xxx = 25 orders
Product yyy = 18 orders
Product zzz = 8 orders

This can be done with the following very light SQL query and a foreach loop.

That will give you the list of products (and product variations, but not parent variable products) of orders count by product for the past 24 hours:

global $wpdb;

$results = $wpdb->get_results( "
    SELECT DISTINCT woim.meta_value as id, COUNT(woi.order_id) as count, woi.order_item_name as name
    FROM {$wpdb->prefix}woocommerce_order_itemmeta as woim
    INNER JOIN {$wpdb->prefix}woocommerce_order_items as woi ON woi.order_item_id = woim.order_item_id
    INNER JOIN {$wpdb->prefix}posts as p ON p.ID = woi.order_id
    WHERE p.post_status IN ('wc-processing','wc-on-hold')
    AND UNIX_TIMESTAMP(p.post_date) >= (UNIX_TIMESTAMP(NOW()) - (86400))
    AND ((woim.meta_key LIKE '_variation_id' AND woim.meta_value > 0)
    OR (woim.meta_key LIKE '_product_id'
    AND woim.meta_value NOT IN (SELECT DISTINCT post_parent FROM {$wpdb->prefix}posts WHERE post_type LIKE 'product_variation')))
    GROUP BY woim.meta_value
" );

// Loop though each product
foreach( $results as $result ){
    $product_id   = $result->id;
    $product_name = $result->name;
    $orders_count = $result->count;

    // Formatted Output
    echo 'Product: ' . $product_name .' (' . $product_id . ') = ' . $orders_count . '<br>';
}

Tested and works.

If you want to get instead the total based on the "today" date, you will replace in the code this line:

AND UNIX_TIMESTAMP(p.post_date) >= (UNIX_TIMESTAMP(NOW()) - (86400))

by this line:

AND DATE(p.post_date) >= CURDATE()

Time zone ajustement using CONVERT_TZ() SQL function
(Where you will adjust '+10:00' the last argument as an offset to match the timezone)
AND DATE(p.post_date) >= DATE(CONVERT_TZ( NOW(),'+00:00','+10:00'))