Scenario softmart, a new australian software retailer, maintains an information system to with invoice and stock control. it has so far made only a small number of sales. the details of the software items it has in stock are shown in table 1. each software item is identified by an item code, but each also has a unique title. each item belongs to one of exactly three software categories, identified by codes (ss = spreadsheet, db = database, wp = word processor); the full names of these categories are not recorded. the list price of an item is the normal price at which the item is currently sold. however, softmart may sell an item at less than the current list price (e. g. softmart may give a discount for bulk orders or to favoured clients, and the list price itself may change over time). there is no rule that enables the unit price (i. e. the actual price charged for a copy of an item) to be derived from the current list price. itemcode title category stock qty list price b123 blossom 123 ss 8 799.50 dl datalight db 10 700.00 db3 database 3 db 5 1999.99 q quinquo ss 6 400.00 sql+ sql plus db 4 1890.50 ts textstar wp 5 500.00 wl wordlight wp 10 700.00 table 1: stock information each customer is identified by a customer number, but the combination of their name and address is also unique. for simplicity, customer name is treated as a character string, and so is address. customers have at most one phone number recorded. table 2 shows sample customer details. customer details may be recorded before the customer actually places an order. once an order is placed, the items are issued to the customer together with an invoice. at the time the data snapshot was taken for the output reports (table 3), only four invoices had been issued. when a customer pays for the items listed in an invoice, the date of payment is recorded. each invoice is identified by its invoice number. every invoice is either paid in full or not at all. table 2: customer information customer# name address phone 001 002 003 starcorp eastpac dr i. n. stein 5 sun st, st lucia 4067 30 beach rd, sandgate 4017 7 sesame st, st lucia 4067 3765 3269 ? invoice# date paid 0501 10/07/19 0502 20/07/19 0503 unpaid 0504 unpaid table 3: invoice information iab201 semester 2, 2019 – assignment 1 – information modelling page 3 each of the four issued invoices is shown below. the invoice header giving the address of softmart is not stored. an invoice includes a table of one or more rows, called "invoice lines". each invoice line lists details about the order of one or more units (copies) of a software item. for simplicity, assume that on a given invoice the same item can appear on only one invoice line. for each invoice line, the item code, title, quantity of units ordered, and unit price are listed. the total charge for the invoice line is displayed as a subtotal. the total charge for the whole invoice is displayed as the amount due. softmart, 46 gallium street, brisbane 4001 invoice#: 0501 date: 03/07/19 customer#: 001 customer name: starcorp address: 5 sun st, st lucia 4067 item code title qty ordered unit price subtotal wl q sql+ b123 wordlight quinquo sql plus blossom 123 5 1 5 1 650.00 400.00 1701.45 799.50 3250.00 400.00 8507.25 799.50 total amount due: $12956.75 softmart, 46 gallium street, brisbane 4001 invoice#: 0502 date: 03/07/19 customer#: 002 customer name: eastpac address: 30 beach rd, sandgate, 4017 item code title qty ordered unit price subtotal q ts quinquo textstar 4 4 400.00 500.00 1600.00 2000.00 total amount due: $3600.00 softmart, 46 gallium street, brisbane 4001 invoice#: 0503 date: 10/07/19 customer#: 001 customer name: starcorp address: 5 sun st. st lucia 4067 item code title qty ordered unit price subtotal q quinquo 4 350.00 1400.00 total amount due: $1400.00 softmart, 46 gallium street, brisbane 4001 invoice#: 0504 date: 20/07/19 customer#: 003 customer name: dr i. n. stein address: 7 sesame st, st lucia 4067 item code title qty ordered unit price subtotal b123 dl blossom 123 datalight 1 1 799.50 700.00 799.50 700.00
you are required to submit the following items for task 1: 1. a list of elementary facts that fully and explicitly verbalise the fact types contained in the scenario description.
2. a conceptual schema model produced using the entity relationship diagram (erd) language, using the barker notation, which fully captures all of the fact types and any necessary constraints.
3. a conceptual schema model produced using the object role modelling (orm) language, which fully captures all of the fact types and any necessary constraints.
4. a textual description of the erd model, prepared for the business owner, as an aid to communicating and understanding the less obvious features of the model (200-300 words)
5. a textual description of the orm model, prepared for the business owner, as an aid to communicating and understanding the less obvious features of the model (200-300 words)