how does the discount get applied on the header of a sales order to the corresponding invoice

AI generated answer (using internal Slack threads):

In NetSuite, a sales discount can be applied at the header level of a sales order and this will be carried over to the corresponding invoice. This is done by using the discount field at the header level of the sales order. This field should already be present on the standard form, but it might be hidden on your custom form. To apply the discount, you don't need to create a different item, you just need to apply it at the header level as compared to the line level. This discount will then apply to your entire transaction. There is also a Rate field, so if you want to apply a discount on the fly, you can just type in a negative rate. For ecommerce sales, you can create a promo code which can be used for the entire transaction. However, if there are items that do not qualify for the discount, you might need to apply the discount at the line level instead of the header level. Please note that discounts can affect taxes, so you need to set up the tax on the discount item correctly. Also, if you are using revenue recognition, you need to be careful as discounts can affect this as well. ****** Disclaimer: This response was generated by an artificial intelligence assistant based on previous conversations from multiple Slack channels, and may contain inaccuracies or mistakes. ******