Quote and order data

One Step Checkout uses Magento's quote and order records. The module adds a small set of columns and copies only the values collected by an active One Step Checkout quote.

Data Quote storage Order storage or output
Order comment quote.order_comment sales_order.order_comment, status history and order_comment extension attribute
Preferred delivery date quote.delivery_date sales_order.delivery_date, success/Admin display and delivery_date extension attribute
Newsletter choice quote.newsletter_subscribe Processed by the post-order newsletter observer; not shown as an Admin extra box
Gift message Magento gift-message quote/order relation Magento gift-message record and Admin Checkout Extras view when a gift-message ID exists
One Step scope marker quote.onestepcheckout_active Used by submit observers to apply the module's required-field and extra-copy rules
Cart-recovery state quote.cart_recovery_sent, claim and retry columns No order column; recovery state ends when the quote is sent or skipped

The order-repository plugin adds the two declared extension attributes when an order is loaded or listed. The module does not copy the newsletter checkbox into a new order column.

Persisted checkout extras on the Magento order view

Primary sources: etc/db_schema.xml, etc/extension_attributes.xml, Observer/SaveExtrasToOrder.php, Observer/SubscribeNewsletter.php, Observer/ValidateRequiredAddressFields.php and Plugin/Sales/Api/OrderRepositoryPlugin.php.