Evaluate Data Collection Methods:

Data Entry Method:

        Barcode: a series of vertical lines with a unique identification code, laser scanners read the bar codes and the information is transmitted to a computer for processing. Barcodes are in wide use in supermarkets, libraries and retail shops. This isn’t suitable for my system because my data is in small quantities and doesn’t need a barcode system, it will be need at further when the company expands and has more products. Also barcodes are used for products that are small and can be moved around, but barcodes aren’t used for selling houses because comparatively less is sold and the product isn’t moved around.

Key to Disk - This is typing the data onto the computer using a keyboard, although this isn’t expensive and is easy to use, it does take quite a lot of time and errors are often caused by this method. But still, this method is practical and simple and can be used for our system. This method doesn’t require the user to be trained a lot and is efficient for small quantities of data. It could be used in my system to enter the product name, and it details. This method will be used mainly for all entering all my data.

Optical Character Recognition: This equipment scans the page containing text and studies each character and compares them with what has been stored. Although some of these can read the text quickly there is an extremely high rate of errors being caused? This will not be used because the equipment is expensive and isn’t reliable.

         Optical Mark Reader: This scans marks and converts them into characters. My system consists of letters and numbers and not marks therefore there aren’t going to be any marks to convert. This method will not be useful for my system.

        To minimise any mistakes or errors in the information put onto the system to calculate profit or loss, there are many methods in which the computer can use to do this.                                                                                                                                                      

Range check- is performed on numbers to make sure that they lie within a specified range. An example a validation rule is that is a company has 20 products it can sell more than 20 products it only can sell 20 or less, so rage check helps reduce making those kind of errors.

Character-type check- makes sure that the correct types of characters have been entered. For example, if text is inserted for house number then the computer will inform the user and not let him carry on until the mistake has been corrected.

Spell Check- This check will make sure that the words have been spelt correctly and the grammar is also right. Suggestions will be given if the words aren’t right.

Validation is cheap and very quick because the computer does it, but it does not guarantee to find all errors. This will minimise errors and therefore is effective. All the mistakes will not be corrected because the computer only does what it has been told to look out for that is why a lot of validations should be used to completely minimise the number of mistakes made.

Data Verification:

Data Verification is checking that what is on the form is the same as what has been entered onto the system, there are two main methods for this.

Proof reading- the user reads the information again and compares the form and what has been entered onto the system.

Re-typing- After the user has typed in the information another member of staff should come and type in the information, the data will only be processed if both entries are identical. It is unlikely that both people will make the same mistakes. The Re-typing method is expensive and time consuming but proof reading will be effective and easy to put into practice.

Output Requirements:

Most of the information that will be on the computer will be on screen mainly but there will be some information that will be printed out on paper. The information that is going to be left on the screen are the main pages, detail about how much each product got sold each month and the monthly staff wages, all these information will be seen on screen mainly because there won’t be that much use on paper .The only information that will be printed out are the Monthly Expenses, Yearly DVD’s and VHS’s and overall expenses, the bills and the yearly staff wages report. All these information will be mainly seen on paper because all these information tell the manager how the company is doing financially. Sometimes different output might be required in different situation for example the Manager has to an presentation to the Board so he might show the Profit on a big screen, because all the people can see and it would be convenient. Sometime the monthly detail of the product might be printed out because the manager might want to check if the data is correct. When the output will be printed it will be sorted in two columns yearly reports and monthly reports.

Backup & Security Methods:

There would be possible threats to my system things like hackers, fire, accidents and breakdowns. I would have network password where the workers know the password, each person has a different password and as they log on it tell the system that person has logged at that time. This would reduce the chance of someone hacking my system, plus the password will change daily so it will make it even harder for someone to hack the system. I would use Nortel Virus software to protect the system from any viruses. I would also make back up after everyday on a CD and will be put inside a fire proof cabinet, to secure the data from fire and accidents and breakdowns. The backup should not take more than 20 minutes at the end of the day. It would be stored on a CD R not CD R/W because the data on that can be erased easily by mistake. While CD R can’t be erased by mistake and the CD’s are cheap.