Database Assignment: Based on the POS & Stock Controller system shown below, design an appropriate ER diagram that reflects the specified system and then extract the mapped tables showing them as flat tables.A Point$-$of$-$Sale & Stock Controller System is an information system primarily used to monitor the sales and stock activities of a company.In the POS & Stock Controller System it is possible to have the following entities:ProductProduct CategoryProduct UnitSalesInvoiceReceive ProductCustomerSupplierPurchase OrderUserThe possible relationships between them can be as follows:The user determines the products $(1$ to N$).$The user can handle multiple invoices $(1$ to N$).$The user can manage the receiving transactions $(1$ to N$).$The user can process the purchase order transactions $(1$ to N$).$Product belongs to a certain category $($N to $1).$Product has multiple product units $(1$ to N$).$Product has multiple receiving transactions $(1$ to N$).$Product is also included in the purchase order transaction $(1$ to N$).$Purchase order will be forwarded to the supplier $(1$ N$).$The supplier will supply the requested products $(1$ to N$).$Product is included in multiple sales $(1$ to N$).$Sales produce an invoice $(1$ to N$).$An invoice is given to the customer $(1$ to N$).$The last part of the ERD process is to add attributes to the entities as follows:Product Entity has the following attributes:Product ID primary key represented with underlineCodeNameUnit PriceUnit in StockDiscount PercentageRe$-$OrdervelCategory ID foreign keyUnit ID foreign keyUser ID foreign keyProduct Category Entity has the following attributes:Category ID primary key represented with underlineNameProduct Unit Entity has the following attributes:Unit ID primary key represented with underlineNameSales Entity has the following attributes:Sales ID primary key represented with underlineInvoice ID foreign keyProduct ID foreign keyQuantityUnit PriceSub TotalInvoice Entity has the following attributes:Invoice ID primary key represented with underlineCustomer ID foreign keyTotal AmountAmount TenderedPayment TypeBank Account NameBank Account NumberDate RecordedUser ID foreign keyReceive Product Entity has the following attributes:Receive Product ID primary key represented with underlineProduct ID foreign keyQuantityUnit PriceSub TotalReceived DateSupplier ID foreign keyUser ID foreign key Customer Entity has the following attributes:Customer ID primary key represented with underlineCodeNameContact AddressSupplier Entity has the following attributes:Supplier ID primary key represented with underlineCodeNameContactEmailAddressPurchase Order Entity has the following attributes:Purchase Order ID primary key represented with underlineProduct ID foreign keyQuantityUnit PriceSub TotalOrder DateSupplier ID foreign keyUser ID foreign keyUser Entity has the following attributes:User ID primary key represented with underlineFullname $($FirstName$,$ MiddleName, LastName$)$ContactDesignationAccount TypeUsernamePassword