9 Sit T3 L1 Databases

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IST Lesson 2 - Introducing core database structure concepts and key terms using MS Excel as a Flat File Database

Transcript of 9 Sit T3 L1 Databases

DatabasesDatabases

Information Software Technology (IST)Year 9/10. Copyright 2007 D. GroomLesson 1. Introduction to databases

Information Software Technology (IST)Year 9/10. Copyright 2007 D. GroomLesson 1. Introduction to databases

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What is data?

✦ Data is the building blocks of information

✦ Text, numbers, images, sounds, video are all types of ‘data’

✦ On their own, single pieces of data are fairly meaningless to humans and computers alike.

What is this image about?

What is this image about?

✦ It is a photo of three people. Our brain is a huge database. We store data and turn it into information all the time.

✦ We see people, the data we get from our eyes tells us one of the people is female and a bride.

✦ We have previously seen a bride and someone has told us what one is. (Its in our database)

✦ We have stored data about a bride. When we ‘see’ this data again, organised in a way we’ve seen before, our brian gives us ‘information’ - It’s a bride.

✦ images give your brain data all the time ...

Look at these two photos. List the data you can see in the photos that you think your brain uses to give you information about them.

✦ Our brain also looks forerrors in the data. Onceit has enough data todetermine informationit will also look forerrors!

✦ What is the potentialdata error in this photo?

✦ You update your owndatabase by either ...

✦ Recording this image asbeing something thatapplies to brides (ieyou expect them tobe in water ...

✦ or else you don’t add wateras data that is neededfor your brain torecognise this imageas a bride.

✦ Bride is only a bride, whendressed like this ANDis standing in water.

✦ Databases makedecisions!

✦ Databases contain lots of individual pieces of ‘data’.

✦ When we put ‘enough’ data together it turns into information.

✦ Sometimes we get ‘some’ information, but it’s not quite right - one or more pieces of vital data are missing ... (what missing on the next slide?)

Databases

✦ What data hasyour brain received?

✦ After processing thisdata, what has yourbrain’s databasedecided this is?

✦ How sure is it?(0%-100%)

✦ WhWhat datais in yourwallet?

Computer Databases

✦ Your brain is an amazing database!

✦ It’s quick, stores plenty of data and can relate one thing to another without you needing to write a program!

✦ Computers are great a processing data too!

✦ But they need humans to organise data for them and to explain the rules of what do with it, when do it and of course how to do it

GIGO!

✦ GIGO means garbage in, garbage out

✦ Databases are only as good as the data in them and the programs ability to store and retrieve it in a way that gives us meaningful information

✦ Put rubbish in, get rubbish out!

Collecting data✦ In order to create a database (which is

just a place to keep raw data and organise it so that it makes sense) ... we need to collect it.

✦ Collecting data requires us to decide what data we need to collect, and what ‘type’ of data it should be.

✦ Let’s try collecting some year data ...

Task 1.0✦ This first task gets you thinking about

you to go about collecting data that you can turn into meaningful information. In future lessons we will begin to analyse and process this data and produce information from it ... but to get started we need to firstly collect it. Read the following slides and set to work.

Task 1.0✦ In pairs, create a survey of 10

questions to ask your family and friends about their lives.

✦ Design a form to fill out and then ask 30 people to complete it.

✦ How are you going to record the data? 30 sheets of paper?

✦ See the next slide for some ideas.

Task 1.0✦ Produce a survey to collect information

about people’s lifestyles.✦ What is your age, what sex are you?✦ What is your favourite number?✦ What is your favourite colour?✦ What are first four digits of your phone

number?✦ How many times have you been

overseas?