1. What are Databases used for? Databases are used to store data for a huge range of uses:
• school registers
• police databases
• library databases
• telephone directories
• electoral register (but to name a few)
2. Data can be stored in these sorts of databases using a variety of methods. These can be split into two categories
• Paper based.
3. What are the advantages to using Computers to store data?
• Do you have an address book or store all your contacts on your phone?
1. data takes up far less space
2. quicker and easier to search for information
3. easier to sort data into order
4. easier to access data
5. back up data more easily
4. How can we capture some of this data? Computer based methods
Barcode Reader – e.g. library databases – get out barcode readers
RFID – Radio Frequency Identification – small chips embedded into products containing product information such as price and weight.
MICR – Magnetic Ink Character ink is magnetised and can be read when put through a scanner e.g. numbers on the bottom of a cheque book.
OMR - Optical Mark Recognition
OCR – Optical Character Sensors
weather sensors, science experiments
5. Manual data capture fill in a form to give name address etc. written down when on the telephone customers asked details over phone and member of staff fills in database.
6. How can the following factors affect the choice of capture method?
The nature of information to be collected (e.g. environmental conditions, location information) cost / availability / ease of use / data security
6. How can you design capture forms to collect data effectively
Design should have:
Lists with options
Information blocked into categories
Heading and sub heading
Data laid out in a clear order
Tick boxes with options available
Polite and concise
7. What is encoding?
Encoding is where information is recorded using letters or numbers – e.g. post codes (CT20 2RB) , train stations (Charing Cross – CHX), airports (London Heathrow LHR) , (Male / Female M/F )
Advantages of encoding - smaller field length helps to reduce size of database
8. How can you help prevent collecting incorrect data?
Validation – Length check – 11 numbers in a telephone number
Presence check - must fill this information into the field
Format check (input mask LL00 0LL) - letters or numbers combination in a Postcode
Range check – numbers entered must be within a certain range.
Check digit – a number at the end of a bar code which is calculated from the rest of the bar
code and checks that the barcode has been read accurately
Data type check – can only enters text or can only enter numbers etc
Lookup lists e.g. Dress size, car models, vet might list animals he treats
Advantages of look up – speeds up entry, reduces mistakes, limits options – can only select what is available.
Disadvantages – the option you want may not be there can be forced to choose the best fit!
||RFID in plain English