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//with id commodity_id
//SQL command to be used: select
QUESTION
Identify at least two other functionalities that should be supported by class Commodities and
write routines for them.
5. The commodity inserted above contain the vendor_id of the vendor offering the commodity for selling. So, we also
need to specify information regarding all the vendors in the table vendors. This may be achieved using the function
insert_vendor of class Vendor.
6. Further, functions delete_vendor and modify_vendor may be used to delete or modify any seller’s information,
as and when required. If the customer selects any product on the website, then the function display_vendor may
be used to display the details of seller offering the product. Suppose the same product is offered by more than
one seller. In such case, you need to list all the sellers along with their details. Here, declaring Commodity_id and
Vendor_id as the composite key will serve the purpose.
package shopping_appllcation;
public class Vendor{ public void insert_vendor (string vendor_tuple[])
//Add functionally to insert a row of vendor named / /vendor_tuple
//SQL command to be used: insert
public void delete_commodity (int commodity_id)
/ ‘Add functionally to delete a vendor with id vendor_id
/ ‘SQL comnnand to be used: delete
public void modify_vendor(int vendor_id, String actr, String new)
//Add functionally to change value of attribute attr //of product with id
vendor_id to new
//SQL command to be used: update
public void display_vendor(int commodity_id)
{
//Add functionally to display details of the vendor
//with id vendor_id
//SQL command to be used: select
}
}
QUESTION
Suppose a buyer want to provide rating to a vendor. Is there any need of special routine for
that? Specify how can you achieve this.
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