Point of Sale (POS) Transaction Process

Start of the Workflow/Process.

Fetch product information (price, tax rate, stock level) from the Product Data Model using a barcode or ID.

Retrieve existing customer data and loyalty points from the Customer Data Model via phone number or email.

Create a new record in the Sales Transactions Data Model containing the header info (timestamp, cashier ID, total amount).

Create individual entries in the Transaction Line Items Data Model for each product scanned in the basket.

Calculate the sum of line items and apply the appropriate VAT/Sales Tax percentage.

Subtract discount amounts or loyalty point values from the subtotal to arrive at the final payable amount.

Sum all 'Price' properties from the Transaction Line Items entries to verify the final transaction total.

Decrement the 'Stock Quantity' in the Product Data Model based on the items sold in the transaction.

Increment the 'Loyalty Points' field in the Customer Data Model based on the transaction value.

Create a task for the Inventory Manager if the updated stock level falls below the predefined reorder point.

Send an email to the customer's email address containing the transaction summary and breakdown.

Send an SMS to the customer's registered phone number confirming the purchase and updated loyalty balance.

Create an entry in the Payments Data Model recording the payment method (Cash, Card, Mobile) and authorization code.

Create a report at the end of the shift aggregating all Transaction Entries to summarize total revenue and items sold.

Delete a specific Line Item entry from the current transaction if the customer changes their mind before checkout.

End of the Workflow/Process.