Lesson video

Hello, I'm Mr. Davidson and welcome to today's computing lesson.

The lesson title today is Creating a Branching Database from the unit Organising Data Using Databases.

Now, databases are such useful tools, and we're going to make some today to help us classify the difference between similar objects.

Make sure you listen carefully, work hard, and try your best.

Let's get started.

By the end of today's lesson, you'll be able to create a branching database.

There are gonna be two main keywords that I want you to look out for today.

The first is branching database.

Now, that's a specific type of database that which we consider is a digital tool, and we use branching databases to identify objects using yes or no questions.

The second key word is identify, and that's as you've probably heard in other lessons.

That's where we want to establish what something or someone is.

We identify different features about objects.

The lesson is going to be split in two parts today.

Let's start with the first, where we're going to identify objects using a branching database.

If we need to identify something, we've got to be able to answer questions about that thing we're trying to identify.

We're gonna practise this on the next slide by you identifying a minibeast by asking and answering different questions.

Minibeasts are going to have certain attributes, so when we ask those questions, if we answer positively, then we can be certain that we're ending up with a minibeast.

So if we say that a minibeast has the following attributes, a minibeast can fly, it can sting or bite, and it makes honey.

Now that we know those attributes, we can check to see what a minibeast is based on answering yes to those attributes.

Now, you might already know what a minibeast is, but you can use the branching tree diagram to help find out for sure.

Let's have a go.

So what we want to be able to do is identify the minibeasts with questions.

Remember, the attributes of the minibeast can be put into a diagram that allows us to follow that diagram to work out if what we are looking at is a minibeast.

Our first was can it fly? So we have two answers to that question, both a yes and a no.

I've coloured the yes branch a darker colour than the no branch because that identifies that that leg of our diagram is going to be where we find minibeasts.

Our second attribute was does it sting or bite? So again, our yes answer to that question will indicate that what we are looking at is still a minibeast because it can fly and it can sting and bite.

The last question we'll ask is, does it make honey? Again, a minibeast does make honey, which means our yes branch shows finally that what we are looking at is in fact a minibeast.

In this example, a bee is a minibeast because it can fly, it does sting, and it does make honey.

Let's check you've understood that.

I've given you three different minibeasts below, dragonfly, butterfly, and ladybird.

Which of these would we be able to identify as what we are looking for based on the following questions and answers? Can it fly? We want the one that does.

Does it sting or bite? No, we don't want one that does.

Does it have any spots? Yes, we want to have spots.

Does it change from a caterpillar? Yes, that's what we want to identify as well, which one of those three matches up with those answers? Well done, it's the butterfly.

Butterflies can fly, but they don't sting or bite, they can have spots and they change from a caterpillar.

Notice how the answers to the questions led us to the minibeast that we were looking for.

So we can see if we ask the right questions, we can arrive at something that we need to identify based on the attributes that the questions are looking for.

We are going to now consider that branching databases do something similar.

So what is a branching database? Well, a branching database is a digital tool for identifying objects using yes or no questions exactly like we just tried previously.

Now that's such an important word to remember.

Let's think about what that definition is.

I've given you a sentence that you need to fill in using the keywords below.

When you fill in those gaps, you'll be able to answer the question, what is a branching database? Have a think and we'll check the answer in a moment.

So let's check that.

A branching database is a digital tool for identifying objects using yes or no questions.

So a branching database has the definition of that.

Now that we know what a branching database is, let's think how we use a branching database.

I've got an example in this picture here of a branching database that's used to categorise different minibeasts.

We can actually click on the link as well if we want to see a version that's been created in some software.

In the example I've got here, I've got the differences between a bee and a fly.

We've got there because we've asked can it fly, which it can, does it sting or bite, yes, both of those do.

But we get to the question, does it make honey? Now we know that bees make honey, so we follow the left hand branch where the thumb is pointing upwards, indicating yes, it does, and that leads us to our final answer of a bee as the minibeast in this particular category.

If the answer to does it make honey is no, then our path followed is to the right, which is the negative response, it does not make honey, which makes it a fly.

I want you to have a go at that now.

You are going to identify minibeasts using a branching database.

You're gonna go to that link that you've got on screen.

You click on the Play button to start, and I want you to answer the questions to identify the following minibeasts.

I want you to be able to find the caterpillar, the ladybird, and the snail.

As you go through, carefully consider the answer to the question and check to see whether what you are looking for matches the question or doesn't, and keep following the paths until you get to the minibeast that you're trying to identify.

Pause the video and have a go now.

I'll go through the answers in a moment.

Well done, that was really fun to do, wasn't it? You should have with the caterpillar, started at the top, as with every other minibeast, and we ask ourselves the question, can it fly? Well, no, caterpillars can't fly, so we follow the thumb that's pointing down.

So the next question, does it have legs? Caterpillars definitely do have legs.

So that leads us to the next question, does it have more than eight legs? Caterpillars do as well.

Does it become a butterfly? Yes, it does.

Therefore, we've identified that our caterpillar has those specific attributes of legs, more than eight legs and becomes a butterfly.

But we can also identify that actually caterpillars cannot fly.

In our second example of the ladybird, we ask again at the very first option, can it fly? It can fly, so then we ask, does it sting or bite, which it doesn't.

We follow to the next question, does it have spots, which it does.

And then we ask, lastly, does it from a caterpillar, which it doesn't.

We therefore correctly identify our ladybird and we can say that ladybirds fly, but they don't sting or bite, they do have spots, but they don't change from being a caterpillar.

And in our last example of the snail, again, starting from the top, doing the same things as we've always done, we ask ourselves the question, can it fly? Snails definitely can't fly, they just sort of crawl along the floor.

Then leads us to the next question, does it have legs? Well, snails don't have legs, so we follow again our no response to the last question.

Does it live in a shell? And we can see there our snail definitely has a shell on its back, it carries its home around with it.

So our answer is positive and we can identify that a snail can't fly, it doesn't have legs, but it does live in a shell.

Let's now get onto the second part of today's lesson where we're going to create a branching database to identify objects.

There's something very important that we need to think about before we can begin to build a branching database.

What do you think we need to know about first? May seem like an obvious answer, but we actually need objects to ask questions about.

We can't make a branching database without thinking about the things that the branching database is going to say about those objects.

We can't describe cars if we don't know what cars look like.

We can't compare different animals if we don't know what animals we're looking for.

We're gonna use some software now to create your own branching databases.

This link here takes you to a branching database piece of software on a website.

I want you to use that tool because it's got images of objects you can use to build your own branching database and think about the questions that you need to ask.

When you get onto the software, you are going to select your own template.

The easiest one to choose is blank, because we've got to think about not distracting us from the information that we need to read.

Sometimes backgrounds can make it difficult to understand the information that we need to read.

You're then gonna choose your own library set.

Now what this is, is all the different objects that you are gonna classify with your branching database.

So we've got some examples there.

We can choose to categorise different aliens and looking at their different features, what they look like, their colour and so on.

Or you can choose to categorise body parts, clothes or food and drink.

I'm gonna choose food and drink, and when I click on that, it gives me lots of different objects that I can choose from to be able to create my branching database, thinking about the attributes of each of these that they have in common or don't have in common.

Now, it'd be quite a lot of work to have to choose to do all of the objects that you can see.

So I want you to choose between six to eight objects to sort.

I'm going to use the cucumber, the orange, the pepper, the pear, the carrot, the banana, the apple, and the broccoli.

Once I've selected my items, I'm now ready to start building my questions about the attributes that these things have in common or the attributes they don't have in common.

There's a little button in the bottom right hand corner called Sort.

If you click on that, it lets you then start sorting these into different categories.

A question box will appear, and then if I click in the question box and type my first question, that helps me categorise some of these things and it'll divide the objects into two similarly sized groups.

So one of my questions could be, is it a fruit? I then need to drag my objects into both a positive and negative response.

So I look at all my objects and I find the ones that I think are fruits.

Then you are going to drag the objects from the top to the correct response at the bottom.

So for my first question, is it a fruit, I drag the objects to the left hand side with the thumbs up where I think they're fruits, and I drag the ones that I don't think are fruits to the right hand side with the thumbs down because I know that they're not going to be fruits.

Sometimes some of the questions can be a bit tricky.

You might not always get exactly the right answer.

So think carefully about what the answer to your question should be.

When you've put all the objects into either the positive or negative response, then you are ready to create your branching database.

So you need to click on Okay, and then repeat the process, asking different questions to sort the objects until you see a message that says your tree is now complete.

Once that's complete, we'll obviously need to test that it works, and we can test our branching database by clicking on the Play button again in the bottom right hand corner.

What you'll see is that your chosen objects will end up in a box like this.

It's important to test as many outcomes as possible, so try and get to each of the different objects following the different branches of your database.

Once you are happy that that works, I'm gonna ask you to answer the following questions.

Do all the questions focus on the correct attributes, have the objects been organised into the correct groups and what could make the database better? Pause the video here and try and build that branching database and then answer these questions.

If you need to, go back and have a look at the instructions again.

Well done, that was quite tricky in places, but you did really well.

Jun has also had a go.

He made a branching database to identify different animals.

So we can see along the bottom of Jun's branching database, he has a sheep, a pig, a fox, a dog, a heron, a bird, an octopus, and a swordfish, and he ended up creating seven different questions.

Does it have four legs, is it a farm manual, does it have wool, does it meow, does it fly, does it eat fish, does it have tentacles? And he was able to categorise using all those questions linked together.

Now, Jun's thinking back to what he did, and he's quite pleased because he thought that the questions were focused on the correct attributes and the objects were organised into the correct groups.

He did spot a problem though.

He thought the fox picture was a cat, and that's okay.

You make mistakes when you use computers, and the good thing about using a computer is it allows you to correct your mistakes quite easily.

He got to that point because he noticed the mistake when it got to the question, does it meow? So he clicked no on the is this answer correct box.

So Jun could have done two different things.

What he chose to do was to delete the fox image and added the cat image to make the branching database work properly.

We can see here now to the positive response for does it meow, we've got a cat, so we've got to the correct place in the database.

Another change he could have made to keep the objects the same was to change the question instead.

Importantly as well, once you are happy with how something works, you should always be thinking about how to make it better.

Jun did the same.

He said he wanted to make the branching database better by including the animal names.

He thought that that would help people to name the objects once they had identified them, which is a really good idea.

Now, some of you may have spotted this already, but there's an Edit button in the corner of each image before you click Play, looks like a pencil.

Once Jun clicked on that, it gave him two fields that he could fill in, title and description.

He was able then to add in a title and a description and then click on Okay.

He was really pleased with how that worked because it improved what he'd done and made his branching database even better for people to use.

So we can see what he did with the stork, he put stork as the title, and in the description box he put a long-legged wading bird, which is a really good description for a stork.

That's the end of the lesson today.

We covered quite a lot and you did a lot of practical activities, but let's just summarise what we've learned today.

We found out that we can select objects to use in a branching database, and it's important to have those objects in mind before we create the different branches.

Without knowing those objects, we don't know what questions to ask.

Once we do have those objects though, we can group them using yes or no questions, and we know that certain objects will follow the yes path and certain objects will follow a no path based on the different questions.

We might not always get that right, so branching databases should be tested, and if we test a branching database and it doesn't do what we need it to do, we definitely need to go back and make changes.

Don't get discouraged if you do have to make changes because we can't get everything right first time.

But computers allow us to make changes to what we've done in an easy way, rather than having to scrap it all and start again.