Ensure that,
quantity of a product is always greater than 0
default date for a sale is the system date
What I have tried:
Product (prodId, prodName, qty, unitPrice, ROL, supplier)
Customer (custId, custName, address, phone, loyalityPoints)
Staff (staffId , staffName, phone)
Sales (prodId, custId, staffId, salesDate)
Supplier (supId, contactName, phone, address)
but I cannot implement the sql code.