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Payment_date           DATE                Date of payment

                                                         Mode  of  payment  such  as  debit  card,  credit  card  on
              Payment_mode           VARCHAR(20)
                                                         delivery, e-gift voucher
        Now, let us understand how these entities are linked with each other in an informal manner.

                                              Belongs to                            Category
                       Commodity


                Offered by          Contains                                               Contains
                                                            Order

                                                                                Placed By
                         Vendor
                                               Contains                                    Buyer

                         Courier                                is made for        Belongs to


                                                           Payment                       Wish List


        4.2.2 Functionality

        Let us  understand  how shopping  applications  may use and  manage databases.  Given below are some important
        functions that are performed by the MINI-MART shopping website:
        1.   First, all the categories whose products are to be made available for shopping are decided by MINI-MART Company.
           For storing the finalised categories in the CATEGORY table, function insert_category of class Category may be used.

           At later point of time, if the company wishes to come up with some more categories, it can do so with the help of
           same function.
        2.   Also, the company may decide to either delete or modify the categories using functions delete_category and
           modify_category respectively.

        3.   If the buyer selects any category on the website, function display_category is invoked to display all the products in
           that category.
          package shopping_appllcation;

          public class Category

          {

          public void insert_category (String categ_tuple[])
               //Add functionality to insert a row of category

               //named categ_tuple

               //SQL command to be used: insert

          public void delete_category (int categ_id)
               / ‘Add functionality to delete a category with id categ_ld.

                //SQL conmand to be used: delete public void


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