The main logical functions in Tableau

0:00Hey, it's Tim here. In today's video, we're

0:01going to be looking at some logical

0:04functions,

0:04specifically the if, then, else, and, and

0:08all functions inside of Tableau. Now, these

0:11are some

0:11of the most used functions. In fact, when

0:13you learn Tableau, this is probably the

0:15most fundamental

0:16function you can pick up. So in today's

0:18video, I'm going to be breaking them down

0:19and I'm going

0:20to be showing you how they work. Okay, so

0:22now to set this up, what I'm going to do is

0:23I'm going to

0:24connect to a previous mock data set that I

0:25'd used before. I'm going to put a link in

0:27the description

0:28so you can have a go at this yourself if

0:30you'd like to. I'm going to hit excel here

0:31and I'm

0:32going to connect to the mock data set. I'm

0:34going to hit open and we're pretty much

0:36good to go. Now,

0:37this data set is essentially about film

0:39genres and roughly how much revenue they're

0:42generating

0:42in each country. The values aren't

0:44realistic, it's just a sample data set. So

0:46let's go ahead in here

0:47to sheet one and we're pretty much good to

0:50go. Now, if I drag genre onto roads and

0:53then country

0:54just in front of genre, we get this nice

0:56hierarchy. We can start to understand the

0:58structure of our

0:59data. You can see that the genre field has

1:01this pipe separator where there is more

1:03than, you know,

1:05one type of film in the same genre. And

1:07then I can bring the revenue field here and

1:10put it next to ABC

1:11and you can also see that we have some null

1:13values. Essentially, we have some values

1:15that

1:16weren't entered into the database. So they

1:17're not nothing, they're not zero, they're

1:19just null. Okay,

1:20so we're not going to solve those problems

1:22right now. Maybe I'll show you how to do

1:23that a little

1:24later on. But what I want to now do is open

1:26up the calculation window to show you how

1:29to write

1:29the first IF expression. So let's go ahead

1:32in here and just type in IF and when we do

1:34that, you see

1:35that it auto completes. And if I select

1:37that, you'll see that on the right hand

1:39side, it shows

1:40us a summary. So Tableau is always trying

1:41to help you to make sure that you're doing

1:43the right thing.

1:44And if I look at this on the right hand

1:45side, it gives you an example of how this

1:47expression should

1:48be written. But I actually think it's

1:50better to think of an IF expression in

1:51another way.

1:52Think of it as if you're asking a question

1:54of Tableau. So for example, if I just put

1:57this in

1:58a comment block by just doing this, you can

2:00also use a new comment blocking feature in

2:032020.4,

2:04but we're just going to do a single line

2:05comment and we're just going to say,

2:06IF genre equals to action, then make it

2:12null. Otherwise, keep the value. Okay, so

2:18this is a

2:18basic thing we're going to do. We're going

2:20to basically create a condition that does

2:22a few things to the data set. And it's

2:24going to make it easy for us to work with

2:26because essentially

2:26I want to remove the values that relate to

2:28action. So let's go ahead here on a new row

2:31. And you'll

2:31see at the moment, calculation contains

2:33errors, we haven't written anything. So let

2:35's go ahead

2:36and actually write something. So now let's

2:38start typing IF, hit enter. And now what we

2:41can do is

2:42type our expression. Now our expression is

2:44essentially some sort of logical check

2:46against

2:47the data. In this case, we're checking

2:49genre equals to action. So the two things

2:51we have to

2:52be aware of is that genre is a string field

2:54. And we also have to make sure that the

2:56thing we're

2:57checking matches exactly to something we

2:59have in our data set. So if I just

3:00highlight that for you,

3:02if I just go here to the square, you can

3:04see the genre here is a string and action

3:07is spelled

3:08specifically this way, we're going to need

3:10to make sure that both of those make it

3:12into a calculation

3:14in the correct manner. So now I'm going to

3:15go ahead and do that straight away. So let

3:17's just

3:17go in here and type in genre. And you'll

3:19see that this comes up. And you can see

3:21that it also says

3:22here that it's a string with the ABC

3:23notation just to the left here, you can

3:25just see that there.

3:26And now that I've selected that I can then

3:29say equals. And then to get action in here,

3:31if I just typed action, even though it

3:33matches the same spelling as our data set,

3:35this wouldn't work because I need to write

3:37a string in here. So let's go ahead and put

3:40a brackets

3:41in front of that, sorry, speech marks in

3:42front of that, and do that again. And then

3:44now we've closed

3:45that off. Now that's going to check the

3:47right thing. Okay, so now we've got our

3:49condition,

3:50we've got our sort of thing for it to check

3:51. Now we need to tell Tableau what we wanted

3:54to do.

3:54So if the genre equals action, then make it

3:57null. Okay, so we're going to go ahead and

4:00do exactly

4:00that. I'm just going to type in then and

4:03then type in null. Okay, otherwise keep the

4:06value. Okay,

4:07so to say otherwise, we essentially need to

4:10type in else. Okay. And now that we've done

4:13that,

4:13we just need to refer to the thing that it

4:15should be. So in this case, this is

4:16actually the revenue

4:17field. Let me just go ahead and show you

4:19this again. The revenue field is the thing

4:21that we're

4:22working with, okay. And this is actually

4:24also what's in here. If I just sort of show

4:26you this

4:26whole column is basically the revenue field

4:28. So we need to make sure that this then

4:31says revenue,

4:31not sum of revenue, because we're just

4:33doing a basic row level calculation here.

4:35But we basically just need to refer to that

4:38. And then now that we're done, we just need

4:40to hit

4:41end, tell us that we've stopped asking

4:43questions, hit enter. And now you'll see

4:45that the calculation

4:46is valid. So let's just go through that

4:48again. If the genre equals to action, which

4:51is a string,

4:52which is why I've got it in speech marks,

4:54then null else revenue. So essentially,

4:57if the genre is action, make this null.

4:59Otherwise, just return the value that's

5:02there in the first

5:03place. Notice I didn't type this properly,

5:05but Tableau is still quite permissive of

5:07how I've

5:07typed it. You can also just write it in

5:09like sentence case and it generally will

5:10still work.

5:11But now I'm going to call this new revenue.

5:13Okay, and hit apply. And then whilst this

5:18calculation

5:19window is open, I'm actually going to drag

5:21that in, in here. So you can see that I don

5:23't have to

5:23close my calculation window for this to

5:25stop working. I'll just drop it in there.

5:28And now

5:28that you'll see if you look very, very

5:30closely here, you'll see that action is

5:33actually null.

5:34So our new revenue calculation is doing the

5:36job that it's supposed to do. Now just to

5:38show you

5:38that this is dynamic, and you can change

5:41this, I'm actually going to go in here and

5:43change this

5:43from action to let's say action pipe comedy

5:46. I need to find the pipe character on my

5:48keyboard.

5:49Oh man, that's a real tough ask to do this

5:51whilst I'm recording live, but I think that

5:53's the one.

5:54And then comedy do that there. And now what

5:57we should see is that this value will come

5:59back

6:00and this value will go null. So let's hit

6:02apply. And that's exactly what's happened.

6:04So you can see

6:06that change is happening. This is our if

6:08statement working correctly. So just to

6:11summarize the basic

6:12function, you need to understand that this

6:14if is essentially starting the logical

6:16expression,

6:17that then essentially starts the bit of the

6:19question where we're saying what to do.

6:21And once we've figured out what to do for

6:24everything else, this is how you define

6:26what's

6:26going on. And so this is really good if you

6:28just want to ask one question of tableau,

6:30if you're just

6:30going to want to give it one condition, but

6:32then the next thing might be that you want

6:34to give it

6:34a range of condition. And that's where the

6:37next sort of tweet to this comes in the

6:39else if

6:39statement that allows you to keep asking

6:41questions. And that's what we're going to

6:43cover next. Okay,

6:44let's get stuck in. Okay, so we've written

6:47a basic function. Now let's make this a

6:50little bit more

6:51complex. Let's say that I want to check if

6:54something equals to action and comedy. Okay

6:58,

6:58so action and comedy as one genre and

7:00action as well. Okay, how do we do that?

7:03Well, there's a

7:04couple of ways to do it, you can either do

7:06it the way I just said it, which is to use

7:08an and

7:08expression to check if something is all

7:10secrets or something else. Or we can keep

7:13asking questions.

7:14So let me show you the first and maybe

7:16simpler way to understand this. Okay, over

7:18here where I

7:18said else, essentially, what I'm going to

7:20do is I'm going to change this, I just

7:22copied it there

7:23by mistake there. So if I go back here, and

7:25I just say where it says else revenue,

7:27essentially,

7:28after this, we basically have an

7:30opportunity to keep asking questions. Okay,

7:33so if the genre

7:34equals action, comedy, then NOS, okay. But

7:37what if here I do this, I put this on a new

7:40line. And

7:41instead of just saying else, I say else if,

7:43and then hopefully, you see where this is

7:46going,

7:46I can now ask the next question. So I'm a

7:48bit lazy, as you all know, I'm going to

7:50copy this,

7:51I'm going to copy this exact statement, I'm

7:54going to put it right here. Okay, because

7:56now I'm about

7:57to check the next thing, okay. And then I'm

8:00going to go on to a new line and put the

8:02else that was

8:03there before here. So essentially, the last

8:06time I checked something, I always have to

8:09end this with

8:09an else statement. Notice this calculation

8:11is valid, but we're not done yet. We always

8:14have to

8:14end the last question with a single else

8:16not an else if you can't just keep writing

8:18else if,

8:19but if you want to ask another question,

8:22then you just keep on going with else if so

8:24,

8:24if you see where this is going, I'm going

8:27to add a couple more questions into this.

8:29But the reason

8:30I'm copying and pasting is because I'm

8:31using the calculation I've already written,

8:33I'm trying to

8:33save some time. And so now we're in a good

8:36place. What I'm going to do is I'm also

8:38going to ask that

8:39question of action. Okay, we'd already done

8:41that before. But now you can see that

8:43happening. And

8:45then what I might do is I might also do

8:46something here in the view. So action,

8:48adventure and drama.

8:50Now let's let's really test my spelling

8:52here. So let's go adventure. I now know

8:54where the pipe

8:55character is. And the what were you doing

8:58drama? Here we go. Okay, so I didn't do a

9:01capital D. So

9:02I've already failed the spelling test. So

9:04action, adventure, drama, then now so what

9:07should we expect

9:08to see? Let's just highlight what we're

9:10going to see first, I'm going to expect to

9:12see action and

9:13comedy as now so that's this one over here,

9:16which is already now action should be also

9:19now so the

9:19value on the right should be now here, then

9:22action adventure and drama should also be

9:24now so what

9:24we're expecting when we hit enters for

9:26those rows to be empty, essentially on this

9:29right hand side,

9:30new column that we've created, let's exit

9:32out of that hit apply, and you'll see they

9:34all go blank.

9:35So this is how you ask multiple questions.

9:38Okay, this is how you sort of start to

9:40stage things. But

9:41this is how you use else if and you know, I

9:43've seen some really nasty things. Okay, I

9:46've opened

9:46up workbooks where they've been like

9:48something silly, like, you know, 50 else if

9:51statements in

9:51a row because they're 50 elements inside of

9:54a dimension. And so people are just asking

9:57the

9:57else if question for every single variant.

9:59I've also seen this used to clean up

10:01datasets, let's

10:02say you've got a category that's misspelled

10:03, you can essentially change the spelling of

10:05that

10:05category with a modified category

10:07calculation. Okay, so whatever you do here,

10:10you just got to

10:11remember that this is the skeleton

10:13framework for asking questions, it doesn't

10:16limit what you can do.

10:17Okay, because what I could do is I can

10:19always replace this null statement with a

10:22whole

10:22calculation. Okay, I can literally do this,

10:25it's quite common for people to do this to

10:27make it

10:27easier to read their calculation, although

10:29say net, then they'll open up sort of a

10:31double space

10:32here. And then they'll go up one line, and

10:35then they'll indent just so that the

10:37question they're

10:38asking is actually there. And then you

10:40guessed it, some people will even do this.

10:43If and then

10:44start asking another if question inside of

10:47this else if statement, okay, so you can

10:49nest these

10:50things to create really complicated logic.

10:53But I always say to people like, you know,

10:55try and solve

10:56that in data prep tools if you possibly can

10:58, because then it makes this aspect so much

11:01easier

11:01to deal with. But if you can't solve it,

11:03and this is the only tool you've got to fix

11:05a problem,

11:06then this is where you should do it. Okay,

11:08so just remember, you can turn any of these

11:11sort of

11:12actions that you do after a then statement

11:14into a whole calculation, you could do an L

11:17OD, you can

11:18use any of the other functions we talked

11:19about previously, you're just simply stip

11:21ulating how

11:22Tableau should treat that portion of the

11:25data that you've defined right here. Okay,

11:27so that's one way

11:29of basically asking multiple questions. Now

11:31, the other way is the more natural way that

11:34is using

11:34something like and or or statements, okay.

11:36And this is a more natural way because that

11:39's how we

11:39talk today. You know, when you go to

11:42someone and say, hey, I'd love to see this

11:44and this, or I

11:45wouldn't mind seeing this or that, okay,

11:47that's how we talk naturally. So this is

11:49another way you can

11:50sort of build the question. So what I'm

11:52actually going to do is I'm probably going

11:55to just leave

11:55this as null here, I'm going to make this

11:57valid, I'm going to hit apply, and we're

11:59just going to

12:00leave it as is so we can open it later on.

12:02I'm going to hit OK. And now I'm going to

12:04open up a

12:05new calculation. Okay. So for this one, I'm

12:07also going to call this and or revenue,

12:14okay, because

12:14we're basically going to try and do some

12:16basic calculations with this. And so we're

12:18going to do

12:19the same thing. I'm going to put my

12:21question right at the top. So I want to say

12:24, if genre equals

12:26action, or action and adventure, then null,

12:33else, revenue. And you can see I almost

12:39fell into the

12:40trap myself, I'm writing it as if it's a

12:42Tableau calculation. Then null, otherwise,

12:44let's just

12:45write this like a human being, you can see

12:47I've been using Tableau for too long.

12:48Otherwise,

12:49revenue, just to keep it sort of, you know,

12:51correct. Obviously, it's going to complain

12:52about a syntax error because we haven't

12:54written anything. But now I think we're

12:56ready to do this.

12:56So let's go ahead and do this. If genre,

12:59okay, let's just make sure this is auto

13:02completed equals

13:04and then what we want to do is action again

13:06, like we did before, I can't spell, you'll

13:09know that. So

13:10we should turn that into a meme or

13:12something. If genre equals action, and then

13:15or action and

13:17adventure, so one or the other, okay, then

13:20let's type in the or statement, you can see

13:23that Tableau

13:24automatically completes that action or and

13:27now this is the this is slightly tricky bit

13:30,

13:30I have to go and ask the whole question

13:32again, the Tableau is not smart, I can't

13:34just say

13:35action or and then the next thing I have to

13:38say, if genre equals action, or genre

13:40equals action slash

13:43adventure. Yeah, I'm just going to put it

13:47like this. And then we're going to do one

13:50more for

13:50drama. So we can actually see the change.

13:53Okay, then. So we've done our or statement,

13:56then no,

13:57else, revenue, like exactly as we did

14:00before, and then we're going to end that

14:02statement. Okay.

14:03And now that's a valid connection

14:06calculation. So let's just break this down

14:09into slightly more

14:10sort of easy to digest things. So let's say

14:13this, if a genre equal action, I'm going to

14:15enter here,

14:16or genre equals action and adventure and

14:18drama, then now else revenue, and so by

14:24doing it this way,

14:25what I've done is I've made it much easier

14:27for someone to come in and just understand

14:29this

14:29as a basic question. In fact, I'd almost do

14:31this, I'd almost put this in on a new line.

14:34And then you

14:34could format it like this, so that it's

14:36easier for someone to just break this down,

14:38yeah, into

14:39its own sort of setup. So when someone

14:42comes in to edit this, they know that all

14:45they're really

14:46dealing with are these sections of the

14:48calculation. I think I just put one tab too

14:52many. I can't get

14:52that perfectly aligned. It's really

14:55annoying me. But if someone comes into this

14:56like this,

14:57it's suddenly easier for them just to

14:58change this. Okay. They just, they know

15:00exactly what's going

15:01on. They don't need the or statement. They

15:04can just get rid of that in one bulk. And

15:05it makes

15:06it so much easier to work with. So this is

15:08one way you can ask the question. And let's

15:10just hit apply

15:11so that it turns up here and or revenue. I

15:14'm going to put it right next to our new

15:16revenue.

15:16And you can see that action exists, which

15:19is there. And it is also null. Okay. It's

15:21actually

15:22over here. I forgot to change the order. So

15:24let me drag this down here on the bottom of

15:27this measure

15:27values pane. And now you can see this is

15:29our and or revenue. I'm going to expand

15:31this so we can see

15:31the names more clearly. There we go. That's

15:33a lot better. So now you can see new

15:35revenue and

15:35and or revenue are doing the same thing.

15:37And the key thing here is action and

15:39adventure drama

15:41should also be empty. Okay. And that was

15:43the same one we used before. So you're

15:44probably thinking,

15:45Hey, Tim, come on. How can I know this

15:47works? So let's change it to drama and add

15:50an extra pipe

15:51and add war. Okay. And now this time and or

15:54revenue should have the value here and not,

15:58sorry, the value here and not handle

16:00revenue war. So there you go. You see that

16:02switched around and

16:03now pretty much good to go. So that's one

16:05way of using the all statements ask more

16:08complicated

16:08questions. But here's the thing. The all

16:11statement works specifically if one or the

16:16other statements

16:17is true. Only one of them has to be true

16:19for this to function properly. So if you

16:21say genre equals

16:22action, but there is no other genre that

16:24says action, adventure, and drama, let's

16:26just say,

16:27let's say there's no genre here called fish

16:29. Let's type in fish. Let's not top a fish

16:32fish.

16:33Hit apply the function still going to work.

16:36Okay. Because only one of these has to

16:39match.

16:39Now watch what happens when I say and okay,

16:43let's type in and so there isn't a genre

16:47that says

16:47action and but there isn't a genre that

16:50says fish. So now that I've done that, let

16:53me hit apply and

16:54see what happens. You see our action

16:56category now returns the value. There isn't

16:59, there is a genre

17:00called action, but there isn't a genre

17:02called fish. And so this whole statement

17:05doesn't match,

17:05which means it goes onto the next line and

17:08returns the revenue. It doesn't do this,

17:11which is what we

17:12asked it to do if both of these are true.

17:14Okay. Now for the more attentive of you,

17:17you'll notice

17:17there is also another big problem with this

17:19calculation is that this could never be

17:21true.

17:22There is no way in this data set that any

17:25single row can both simultaneously have a

17:28genre called

17:29action and a separate genre called fish.

17:32Even if I chose another value that did

17:34exist, for example,

17:35action adventure and sci-fi, it couldn't

17:37simultaneously have the same values at the

17:40same time because they're on different rows

17:42. So the other catch with the am function is

17:44you have

17:45to make sure you are checking different

17:47things. And that's why here in the second

17:49one, you actually

17:50have to change this to check a different

17:52column of data or a different condition. It

17:54could be a

17:54different expression, but it just has to be

17:57different in some way to this first item,

18:00because if you're checking for something

18:02that is essentially going to happen on the

18:03same row,

18:04then this am function will never compute

18:06anything back. And so nothing will ever

18:08match.

18:09So let's change this one here to a country.

18:12Okay. And what I'm going to do is I'm going

18:15to check if

18:15the country equals France. Okay. And what I

18:18will do is not double equals, single equals

18:20. I'll just

18:21do this F A R A N C. Shout out to anyone

18:24watching the video from France. So here we

18:27are. If genre

18:28equals action and country equals France,

18:31then return null, otherwise revenue. Now,

18:34in order

18:34to do this, what we have to do is go to the

18:37action area and just select keep only.

18:39There's three

18:40items which just have action. So let's keep

18:43only. And now you can see we get France,

18:45Japan,

18:46South Africa, United States. I actually had

18:48four items. I think I was already selecting

18:49one. And so

18:50there's three more. So now here, if we go

18:53and check this genre equals action and

18:55country equals France,

18:57what we should see is a null here on this

18:59line. So let's go ahead, apply. And now you

19:03see the

19:03am function is working. So the am function

19:05allows you to check two different things.

19:08Also note again,

19:09this is again quite permissive. I didn't

19:10put the square brackets. I always like to

19:12put the square

19:12brackets just because that's how Tableau

19:15itself types it. But if you just type it as

19:17a word and

19:18you know, spell it exactly like the colon

19:19name, Tableau will sort of let you get away

19:21with it.

19:21So you'll see that still works. So that's

19:24the and or all function. Essentially, they

19:26do two

19:27different things. An all function lets you

19:29check items within the same dimension as

19:31well as other

19:32conditions that can be across multiple

19:34dimensions. But the am function won't let

19:36you check the same

19:38thing if it happens to happen on the same

19:39row. In this particular instance, we're

19:41writing only

19:42row level calculations. Essentially, this

19:44is not aggregating anything. There's no sum

19:46here. There's

19:47no average. We do aggregate the eventual

19:49values here on the left hand side. But we

19:51're not doing

19:52that in our calculation. So at a row level,

19:54there's no way that you could ever have two

19:57genres on the same row, if that makes sense

20:01. So that is the if and else else if and the

20:04all

20:05functions that have covered in one video.

20:07Now, there is one more if function that I'm

20:10just going

20:10to quickly sneak into this if that's okay.

20:14And that is essentially the if null item.

20:17So if I

20:17just type in if you'll see that there is

20:19this if null and actually there's also the

20:21IIF. So I never

20:23know how to say this. If someone has had to

20:24say this correctly, let me know. It's kind

20:26of like if

20:27or IF or I don't know. I don't know. How

20:30should you say double IF? Who knows what

20:33that should be

20:33called? Because that does need to be a

20:35different name. So you can sort of name it

20:37appropriately when

20:37you're talking to people about it. But I'm

20:39going to show you those two next. We're

20:40going to get

20:41stuck in and just very quickly show you how

20:43those works. They don't take long to cover

20:45at all. And

20:45in fact, the if function, the second one

20:48here is actually a sort of a super speedy

20:50hack for writing

20:52the slightly longer versions that we've

20:53been writing all along. If you're only

20:55going to be

20:55checking something small. Let's go ahead

20:57and try that out. Okay, so what I'm going

20:59to do is I'm

20:59going to hit okay. I'm going to close this

21:01calculation. I'm going to open up a brand

21:02new

21:03sheet. I'm going to build out the same view

21:05, country, genre and revenue. I'm going to

21:08bring

21:08the old value for revenue that we had. Okay

21:12, now to try this first one. So the if null,

21:15let's create a calculated field and let's

21:17just go in here and type if. I'm just going

21:19to double

21:20click if null and it will bring it into the

21:22view for us. And then we're just going to

21:24check revenue.

21:25Okay, and basically what this allows you to

21:27do if you look at how it's been written on

21:29the right

21:30and here on the left. It's telling you. So

21:32it's basically checking the first

21:33expression. If this

21:34first expression is null, then you just

21:36answer a comma and then you tell it what it

21:37should be

21:38if it is null. So if null, then just put in

21:41a zero. Okay, and I'm just going to call

21:43this revenue

21:45if null. Yeah, so let's just go in here and

21:49do this. And you can see the calculation is

21:52valid.

21:53Hit apply. And now you'll see that that's

21:55in there. Let's drag it into our view. Let

21:58's make

21:58sure it goes into the box. And now you'll

22:00see, especially in this particular row, let

22:02me just

22:02annotate this for you. So in this row here,

22:05and in this row there, you will see that it

22:07's actually

22:08returning a zero. So it's a lot simpler and

22:10it's a lot easier than writing something

22:12like this.

22:13This is actually what you would have

22:15written if revenue. In fact, that's not

22:18what you would have

22:20said if is null. In fact, let me just do

22:23this. This is what you would have written

22:26to get the

22:27same result. Let me just comment that out

22:29so you can see the actual if is null. There

22:34you go.

22:35Is null revenue. So you can see the actual

22:37calculation. If is null revenue, then

22:40zero else revenue. Okay, end. So this is

22:49what you would have written to do the same

22:51thing. And you

22:52can see how much shorter and efficient this

22:54is. It's just much easier to write. Does

22:56exactly the

22:56same thing. If I hit apply, you'll see the

22:59same result comes back out. Okay, so that

23:02is a very,

23:02very sort of nice thing to have and be

23:04aware of. If all you're doing is checking

23:06if something is

23:06missing a value, you can just very simply

23:09replace it. You'll also remember that this

23:11actually does

23:12exactly the same thing as a function we did

23:14before, which is the ZN function, which

23:16essentially

23:16goes and looks after nulls for us in our

23:19data set. So again, that's another thing

23:22you can do if you

23:23were sort of want to optimize for this

23:25particular check. There's three ways of

23:26writing the same thing

23:28in one. So that's the if null function

23:29covered off. Now let's have a look at the

23:32double IF. I'm just going to call it the

23:33double IF function. So let's go hit apply

23:36and hit okay

23:37to close that off. And now that's in the

23:38workbook. I'm going to have this workbook

23:40in the same folder

23:41as the mock data that you're downloading.

23:43So you can go ahead and download that too.

23:45Okay, now the

23:46next calculation we're going to write is

23:47create a calculation field. We're going to

23:49keep everything

23:50as is. And this time I'm going to go in

23:52here, type in if, and you'll see that this

23:54I, double IF is

23:56just right there. I'm just going to bring

23:57that in. And this now has three parts.

23:59Essentially,

24:00this allows us to ask to write, this allows

24:03us to write an if then else statement in

24:06basically three

24:07expressions. So the first thing is the test

24:09. So I'm going to do, I'm going to do a

24:11little check.

24:12So just say genre equals action. Let's do

24:18this action. Okay. And instead of writing

24:21then,

24:22all you need to do is a comma. Okay. And

24:24now you just need to say what would happen

24:26if this is the

24:28case. So in this case, I'm just going to

24:30write null. Okay. And then the else

24:31statements comes

24:32after the next comma. And in this case, we

24:35're just going to do revenue. Okay. Just to

24:37keep that nice

24:38and simple. And then what I'll do is I'll

24:41call this IAF revenue. Spell out correctly.

24:45And now

24:45that's basically the statement. And it

24:47basically saved us the trouble of having to

24:49write one of the

24:50previous functions we did. So if I just go

24:53in here and pick out the new revenue here,

24:55if you actually

24:56write a calculation, then you put your

24:58cursor into it. It shows you what's inside

25:00of that calculation

25:02over here on the right side. So you can see

25:04we built this out a little bit, but you see

25:06,

25:06we had to write if genre equals action,

25:08whatever comedy, then null, else, revenue,

25:12end. And this

25:13just allows us to avoid having to do that.

25:15You can't do multiple checks, but if you're

25:17only

25:17doing one check, this is the much faster

25:19and efficient way of doing it without sort

25:22of

25:22getting yourself in a twist. So that's

25:25pretty much it for the if functions, the I

25:28FF,

25:28double IF even, that's an athletics

25:31association. I think that's an athletics

25:34association,

25:34but nevertheless, this is a very nice,

25:37simple function you can use. The if

25:39statements,

25:40you use them all the time. I probably use

25:42this function two or three times a day when

25:45I'm deep

25:45inside a Tableau workbooks daily. And if

25:47not, I use it to fix very quick problems. I

25:50sometimes

25:50even use it to create filters in workbooks.

25:53I use it to create conditional coloring

25:56sometimes.

25:56It's a very functional, very useful

25:59function that if you don't know how to use

26:01this,

26:02you're going to struggle with Tableau. It's

26:04literally a core foundational function.

26:06Everyone needs to know how to use this. If

26:08this is the first thing you learn, great.

26:10If you've just

26:10started Tableau and this is where you are

26:12and you understand this, you're going to be

26:14great

26:15with Tableau. Okay, that's pretty much it

26:17for the video. This has been a little bit

26:18of a long one,

26:19but I didn't want to sort of bring out all

26:21these sort of side topics. And so I've

26:24covered a whole

26:24bunch of functions in one video. Hence, the

26:27length is a little bit longer and hopefully

26:29you go off

26:29and find new ways and exciting ways of

26:31using this. In a lot of these videos, I'm

26:33keeping the

26:34explanation simple and in tables. I'm not

26:36building visualization because if I start

26:38to add in the

26:39complexity of building visualizations as

26:41well, these videos will go on for half an

26:43hour and 40

26:43minutes. And to be honest, there's lots of

26:45other people doing whole built out examples

26:48on YouTube

26:48for you to go and find out. But if you're

26:50just getting started and you just want to

26:51understand

26:52the fundamentals, this is where to be. Okay

26:54, thanks for watching. You know what to do

26:56at the

26:56end of the video. If you've enjoyed it,

26:58please subscribe, please like, please share

27:00. And if you

27:01haven't, let me know in the comments what

27:03you'd like to see instead. So I am working

27:05through a

27:05whole load of content. At the moment, it's

27:07functions. So please definitely let us know

27:09what you'd like to see. And we'll get there

27:10in the end. Alright, thanks for watching.