For this new system I have decided to use the bare minimum. This is because when I spoke to Mr. Williams he said… “Well we are not made of money; a cheaper system will be much approved. ” Also this system will need to be set up and running in one day. “We only close on Sundays and hopefully it will be enough time to get the system running” This may cause problems as there are many things that may cause problems. 2 – Design 2. 1 – Alternate Methods It has been decided that the new system is to be computerised. However there are many different types of programs that can be used for this new system.
I have decided to use Pascal to create the program needed for the stores new system. This is generally because I am used to coding with it and it allows me to make a specified program at a low cost. It will mean having to write all my own user documentation and may take time fir me to write the code for the program. A useful feature about Pascal is that it can utilise procedures to perform a variety of tasks. The code I use can be easily amended if mistakes are made and it will be of low costs. 2. 3 – Identification of procedures For the new system I will have to introduce a number new of new or amended procedures.
Processes Adding a Stock it em When a new stock item is purchased and arrives at the store, immediately a record of the stock is made. Data requirements Number Unique stock number given to that item only Title Name or title of the stock item Description Description of what the stock item is * Price Price of the stock Status Status of the stock: Available Unavailable Discontinued Problems Solved Once the stock item has been added to the file it can not be deleted, just modified. And because it is saved to file there are no worries about the presentation of the writing.
The Id of the product may be entered into the program – the program will search the file and find the stock details with the corresponding ID number. Data Requirements Stock Number A unique stock number given by a member of staff Problems Solved This displays just the item searched for, it will display all the properties of the stock item and tell the staff member or customer if the item is Available, Unavailable or Discontinued. View All Stock This will display all the stock on the stock file weather it is available, unavailable or discontinued. Data Requirements No Data Requirements Problems Solved
Data requirements Password A password must be entered to get access to this section * Stock Number The unique stock number given to this item Problems solved Again this means you do not have to go ranting and raving through files to find weather the stock is available or not as it is displayed on the screen. Once access has been gained to the modify stock section the stock number is required, after this has been entered you are prompted to change the status to A, D or U, this will be saved to the stock file for further reference. 2. 4 – File Structures For the new system, there will be 2 files at CP3.
There will be a Stock file holding all the stock records, and a password file allowing you to change the password. I will use the record structure stock=record, with the fields stocknum, title, description, status, price. Staffnum is the only key field as it gives each item of stock once added a special number that is unique to it. If there is a stock number that has been entered, and the user enters the same number the one currently there is simply overridden. To prevent this you would have to use Validation, and I will not be using this until the second year of the project.
To be able to store records firstly you need a file on your local hard disk, and second a command in the program that assigns a certain variable to the record structure, and the file on the local disk. To do this I will do the following: In the global variables I used a variable called – stock_file : file of stock; This will make it possible to then link the assign line to the record structure. When I wanted to write or read stock I simply entered the line assign(stock_file,’C:stock. dat’); and reset(stock_file); to open the file. Files stored in the stock file are determined by the stocknum given to them.
As this is unique there can be no 2 records in the same place. This then gives us the option of direct access (instead of looking for the file, going straight to it using the seek command i. e. instead of searching all of the map for a hotel you use a grid reference which directs you to the position of the hotel. This grid reference is the same as the seek command). To display all of the records within the file you can simply use the While not eof command in a loop to display each stock item and its linked variable i. e. description, title, price.
When the user wants to modify, view a stock item he/she simply enters the corresponding stocknum into the program and the program automatically seeks the position in the file and displays the stock record to the screen. This process is known as direct access, explained above in brackets. To search by the title of a item of stock, which I will included in the program, the program simply seeks to the start of the file stock. dat, then reads each item into a variable while not eof. The system then proceeds to checking if the title that has been entered is the same as one in the file in sequential order.
Allows Current Stock to be viewed General File Description. This file contains all the various records saved within it. New records can be added and record saved on the file can be modified. Record name General record description Stockrecord Record of all stock details Fields. Field description Field name Format Decimal places Validation check Unique Identifier Stocknum Integer None None Stock title Title String 20 None Stock Description Description String 15 None Stock Price Price Integer None None Stock Status Status Char None None Designed by Craig Pickrell Date : 12/05/02 Approved by Craig Pickrell Date : 12/25/02 2.
4 – Testing Strategy To Test the system I will be using several methods of testing such as Beta and top-down. Beta testing consists of giving the program to others to test and go through before the real product is given out. This system helps spot bugs early and can give designers feedback about what else he/she might include. Top-Down testing consists of the skeleton of the complete system being tested, with individual modules being replaced by ‘stubs’, which may for example display a message to say that a certain procedure has been executed. As individual modules are completed they are included in subsequent tests.