Tableau Prep Builder: The Interface and philosophy (Part 2 of 7)

0:00Okay, so in the last video, I took you

0:04through inputting data into Tableau Prep.

0:07And at this point, now we're about to start

0:09to work with the main concept of Tableau

0:11Prep.

0:12So what I wanted to do first before diving

0:14into the product is just to do a little

0:16recap

0:17of the next step and also talk a bit about

0:19the interface.

0:20So we've covered how to connect to files as

0:23typically the first thing you want to do.

0:25Now what I want to do in this video is

0:27slightly different.

0:28I actually want to talk about Tableau Prep

0:30's philosophy, how you go about working with

0:32data in Tableau Prep.

0:33And I also want to introduce you to the

0:35visual dictionary that's used inside of

0:37Tableau Prep.

0:38So here we are in the Tableau Prep

0:40interface.

0:41On the very left-hand side, you've got what

0:43's called the connection pane.

0:45Here you'll find your connections.

0:46You saw this in the first video, and you

0:48can see here a list of the possible data

0:50sources

0:50you can connect to.

0:51As ever, these are constantly updated to

0:54look out for those over time.

0:56Now in this main section of the canvas, you

0:58've got your recent flow.

0:59So you can actually see some of the work

1:01flows I've been working on very recently.

1:04And at the very bottom here, you can see

1:06some sample flows.

1:07So this is a sample flow that everyone

1:09should have.

1:10You can simply click on these, open them,

1:12and you should have Tableau Prep open up

1:14that

1:14flow.

1:15Now if I just open up a new instance of

1:17Tableau Prep, I'll just show you one last

1:19thing, and

1:20that's the discover pane here on the right-

1:22hand side.

1:22If I just go to full screen here, the

1:24discover pane is really useful.

1:26If you're trying to learn Tableau, it has

1:27some really good starting points.

1:29You'll see here they actually have a very

1:31similar sort of introductory video.

1:33And in many ways, these are actually a must

1:34.

1:34It's really important videos to go have a

1:36look at, and they're great resources put

1:38together

1:39by Tableau themselves.

1:40Now if you want to change this view from a

1:42grid view, you can do.

1:43You can just click on this icon, and you

1:46get a list of workflows and what's going on

1:48.

1:48And you can also see how many outputs, the

1:50location of the file, when it was last

1:52opened.

1:52So in many ways, this might be a more

1:54useful view for you if you work with a lot

1:56of files.

1:56At the very top, you've obviously got the

1:58ability to open a flow that is already

2:00existing,

2:00or you can hop right into your process and

2:03just connect to some data.

2:05The last thing you'll see here is on the

2:06very bottom right, you'll see a prompt to

2:08update

2:08to a new version.

2:09Because Tableau Prep is constantly being

2:11updated, there's always this ability to

2:13update to a

2:13new version.

2:14So it's always worth checking that out.

2:16Okay.

2:17So we'll come out of the full screen, and

2:19we'll head back to our first flow that we

2:22opened up.

2:23Now, one thing to bear in mind is that

2:25unlike Excel, where you do your steps in

2:27this sort

2:28of flat structure, in Tableau Prep, you

2:31think of your data preparation and your

2:33sort of

2:34processing of data as a flow.

2:37It has a direction from the start to the

2:39end.

2:39You have your outputs on the left, the

2:41start, and you have your outputs on the

2:42right, the

2:43end.

2:44The end is basically the final output,

2:46whatever you then take on to another

2:48analytics tool

2:49or export to a database or send as a file

2:52to a colleague.

2:53That's always the final step.

2:55Now, in any particular flow, you can have

2:57multiple outputs, and therefore you can

2:58have

2:59multiple final steps.

3:01In this particular case, I could be

3:04creating a budget.

3:05And in this particular step, I could

3:07actually be aggregating the actual figures

3:09for a particular

3:10year, maybe because my future budget is

3:12based on a certain percentage of this year

3:14's performance,

3:15and this output is actually this year's

3:18performance in real time.

3:20Now, in between your output and your input,

3:23you have all these steps.

3:25And in Excel, what you have to do is you

3:27have to make sure you do things in the

3:28right order.

3:29And if you've done something wrong, you

3:31have to go back and change it, or you

3:33change your

3:33calculations and you make sure that

3:36everything references every single cell

3:38correctly.

3:39In Tableau Prep, that mistake is slightly

3:41harder to make because everything happens

3:43in a sequential order.

3:45The visual nature of the product means that

3:47you have to actually think about the way

3:48you're

3:48going to process your data in a much more

3:51logical way.

3:52You can see the relationships between how

3:54your data comes together, and you start to

3:56get some visual cues about what's going on.

3:59And so your flow is essentially the whole

4:01journey of your data from start to finish,

4:04and that's what we're looking at now.

4:05Again, if you're new to Prep, don't worry.

4:07I'm going to go through all of this at some

4:09point throughout this series, so just tune

4:12in.

4:13And what I want you to do is pay attention

4:15to the visual dictionary.

4:16Now Tableau call this the visual dictionary

4:18because it's basically a visual information

4:21system that allows you to understand what's

4:24going on.

4:25But what exactly do they mean by that?

4:27Well, they have this sort of mechanism

4:29whereby every single process or every

4:31single tool

4:32that you will add here in Tableau Prep has

4:35its own visual sort of design.

4:37So if you look at this, you have the main

4:40data types here, so you have branches,

4:42aggregate

4:43steps, pivots, joins, unions.

4:47You have the capability to do some

4:49scripting with Python or R, and also the

4:51ability to

4:52output a file.

4:53So if I just relate that a little bit to

4:55Excel, these are the kind of things you

4:57might do.

4:58For example, the aggregation step, you

5:00might highlight a column and then add it

5:02all up

5:02to get a particular number.

5:04You might pivot your data because it's in

5:06the wrong shape.

5:07You might do a VLOOKUP in Tableau or in

5:09databases, that's typically a join of some

5:12sort.

5:12Or you might want to put, let's say, three

5:15tabs with the same data, but in each tab

5:17you

5:17have data from different months.

5:19You might decide to union them together.

5:21As you start to see, each of these

5:23processes has a particular name in Tableau,

5:25and these

5:26names are typically derived from the

5:28database world, so the data architecture

5:30and so on

5:31and so forth.

5:32So if they're new terms, don't worry, these

5:34are terms that exist in other tools and

5:35philosophies,

5:36so it's worth investing a bit of time

5:38understanding these.

5:40Now the second thing to understand is that

5:42Tableau Prep uses this concept of a flow,

5:45and a flow is essentially what we're

5:46looking at now.

5:47So if you go from left to right, you have

5:49your input here on the left-hand side, and

5:52on the very far right-hand side you have

5:54your output.

5:55Now you will notice that there are two

5:57outputs in this particular flow.

5:59That makes sense because in some processes

6:01you might want data captured from a

6:03particular

6:03point.

6:04So if you're doing a budget process, you

6:06might want an output of your budget, but

6:08then you'll

6:09also might want an output at the end of

6:10your process to show you how you're doing

6:12against

6:13the budget.

6:14And so these two outputs make a lot of

6:16sense, and those might then go into a Table

6:18au workbook

6:19or into some other sort of data system like

6:22a database or some other analysis.

6:24Now between your outputs and inputs, you

6:27have what are called steps, and these steps

6:30are

6:30actually these individual icons you can see

6:33here, and the main thing to understand is

6:36these steps do different things.

6:38So as you saw before, each step sort of has

6:41its own grouping, but this particular step

6:44is a simple calculation step.

6:46So if I go in here and I just say, I

6:48actually have to go and make sure I do this

6:50on a line

6:51because I've already got an output.

6:53So if I click on the line, I insert a step,

6:58okay?

6:59If I go back one step and instead I click

7:01on the very end of the object, I insert a

7:04branch.

7:05So Tableau is understanding the difference

7:07between me intercepting this path and me

7:10spinning

7:11off this path.

7:12So it's about sort of taking your data

7:13processing into different directions.

7:16If you think of an Excel, this is like

7:17copying all the data in one particular tab,

7:19putting

7:20it on a new tab, and then trying out a new

7:22calculation.

7:23This is the exact same step here in Tableau

7:27Prep.

7:27If I zoom out a little bit, you'll see that

7:31each of these flows has a line, and these

7:34lines essentially dictate the direction in

7:37which the data is moving.

7:38So if I was to remove this step and then

7:41just hit run, you'll see that my data goes

7:44from

7:44left to right, okay?

7:46When it's actually running the flow, my

7:48data streams from left to right, when it's

7:50done,

7:51I get the output over here.

7:53Now when I click on this particular line

7:55and I just bring this down, you'll see that

7:58I

7:58get this pane that pops up and I get these

8:01scrolling lines coming out across the top.

8:04What this shows me here in this particular

8:07section is a preview of the data at this

8:10particular

8:10point.

8:12So unlike Excel where I have to capture

8:14each tab and the process for each tab, and

8:16then

8:17I have to spread that across multiple

8:19sheets or I run some sort of SQL in the

8:21background

8:21that isn't visible, Tableau Prep actually

8:24shows you each of the single steps required

8:26.

8:26So here you can see that I've got two steps

8:30.

8:31One is a rename.

8:32In fact, I've got two removed steps and one

8:34is a rename, three steps in total.

8:37And if I go over here to the left-hand side

8:39pane, I actually get the detail of those

8:41and

8:41the order in which they're applied.

8:43I can move these around and it just changes

8:45the order of the process.

8:47But it's important to bear in mind that if

8:49I was, for example, to move this rename

8:51option

8:51to the top, it might fail because what

8:54happens here is that this step might need

8:57to happen

8:58before this step.

8:59So these steps are sequential.

9:00You have to bear that in mind in terms of

9:03the way you process.

9:04The other thing you can do, which is quite

9:06hard to do in Excel, is you can actually go

9:08back several steps.

9:09Let's say you do a calculation or an

9:11aggregation and you're not happy with it.

9:13By just simply clicking on the first step,

9:15I actually go back to that original step

9:17and

9:17I can undo that step without interfering

9:19with some of the future steps.

9:21So removing this top selection here doesn't

9:24actually interfere with any of these two

9:26steps.

9:27Okay?

9:28And of course, I can always go back and

9:30undo that.

9:31Now, if we look throughout the entire flow,

9:34you'll see that this visual information

9:37system

9:37remains broadly the same.

9:39For every single step, you'll always have

9:42the preference pane here on the left-hand

9:44side, a toolbar that goes across the top, a

9:47view that shows you the results summarized.

9:50And if I push this up a little bit, a view

9:53below here that shows you the table, the

9:55tabular

9:56detail.

9:58If I go to another flow, let's click on the

10:01union, you'll see this step has a slightly

10:04different settings pane because it's trying

10:07to show you the way in which the data

10:09unions.

10:10I can also see any changes that have been

10:12made during the step here.

10:13Again, I still have my toolbar, I have my

10:16summary, and again, I have my table.

10:18Now, if I want to change what's in this

10:20view, I can actually go over to this

10:22toolbar here

10:24and you'll see several things.

10:26This view is the one I'm currently on.

10:28If I click on the second option here and I

10:30show the data grid, it actually hides the

10:32summary and I just get to see the data as

10:35it almost looks like in Excel.

10:37Imagine these as column headers and these

10:40are simply my rows.

10:42And then maybe I might want to view where I

10:44don't want to see my data, I actually just

10:45want to see the column headers and I want

10:47to see what changes have been applied to

10:49them

10:49if at all any.

10:51And I can also get this sort of visual

10:53system that shows me the color of the

10:54streams where

10:55this data has come from.

10:57You see, in this particular step, I have a

11:01purple, a green, a blue, and I'm going to

11:04say a teal color.

11:06So you can see these four colors here.

11:08Those actually correlate with these colors

11:11up here.

11:12So this visual system is not only

11:14communicating the particular sort of paths

11:16that things are

11:17coming from, it matches what's actually in

11:20the flow.

11:21So I can look at this and say file paths

11:23are only coming from the green flow.

11:25If I just zoom into that, you can see that

11:27's the color green.

11:27And then if I zoom back out, you'll see

11:30that this is the only particular output

11:32that's

11:32giving me a file path.

11:34And you can see the columns right there.

11:36And then if I want to see what's actually

11:38in there, I can go back to my data grid by

11:40clicking the second icon here on the right-

11:42hand side.

11:43And then if I want to go back to my summary

11:45view as well with the data grid, I can do

11:47that as well.

11:49Now this tool pane, we'll go into this in

11:50more detail throughout this series, but it

11:52's

11:53always important to bear in mind that it

11:55changes depending on what you selected.

11:57If I click on the canvas, the tool pane

11:59actually disappears altogether.

12:01If I click on a particular step, it reapp

12:04ears.

12:05But the number of options that you get here

12:07in this pane change depending on what you

12:09select.

12:10Now if I want to hide this pane, even

12:12though I've got this particular tool

12:13selected, I

12:14can just hit this down button and it

12:16disappears.

12:17Now, the last thing I want to introduce you

12:19to is this little summary window here on

12:21the

12:22bottom right-hand side.

12:23You can actually see that I can collapse it

12:26and close it just by clicking this arrow to

12:28the bottom left-hand side of this square.

12:31I can also take this icon here, and this

12:34will get the flow to fit in my view.

12:36Let's say that I zoom out too far.

12:39If I click that, it goes back to almost 100

12:42%.

12:42If I zoom in, I can again hit that button

12:45there to go back to how I like it.

12:48Another shortcut you can do is hold Ctrl+

12:50to zoom in and Ctrl- to zoom back out, and

12:53that will work.

12:54If you're on a Mac, it's Command- and

12:57Command+.

12:58Okay?

12:59I hit that icon again to go back to 100%,

13:03and then we'll go back out.

13:05Now, the last thing I want to show you in

13:08this sort of step is the Alerts pane.

13:11The Alerts pane is over here to the top

13:13right-hand side.

13:14This is where you'll typically see errors.

13:16If there are any errors in your flow, for

13:19example, if I was to duplicate this step

13:23and

13:23paste it, I'm going to get an error.

13:26If I click on this tool, you'll see the

13:28error is actually highlighted here.

13:30The issue here is that I've created another

13:32output that writes to the file that I'm

13:34already

13:35writing to, so I can't possibly write to

13:37one file from two different places.

13:39So Tableau has thrown me an error.

13:42It will try and categorize them for you as

13:44well.

13:44So there are also warnings.

13:46Warnings are typically things you should be

13:48aware of, but don't necessarily cause an

13:49issue

13:50in terms of the way the flow works.

13:51So this is also something to bear in mind.

13:54Now, the last thing I want to highlight are

13:57these lines that go in between these

13:59individual

14:00steps.

14:01If I just remove this output so we don't

14:04get an error.

14:05As I showed you before, when we click on a

14:07particular column, let's say we go to our

14:10data summary view and we click on the

14:12Discount column.

14:13They go darker to show where a particular

14:17column is coming from.

14:19So this Discount column that I've selected

14:21is making this flow go darker on these

14:23particular

14:24lines because a Discount column actually

14:27comes from all four of our files that have

14:29gone

14:29into this.

14:30So we have our input steps, we have our

14:33cleansing steps here.

14:34We then have a union step, then a join step

14:37, another cleansing step, an aggregation

14:40step,

14:41another join step, and then an output.

14:44And that's where the discount field is sort

14:47of flowing from and flowing to, if that

14:50makes

14:50sense.

14:51Now, as we work throughout this series, I

14:53'll jump into way more detail about each of

14:55these

14:56steps and we'll be able to sort of dissect

14:58them.

14:59This visual system is new.

15:01Tableau Prep itself is a very new product

15:03at the time of this recording.

15:04It's been out for about a year.

15:06So this is going to change very, very, very

15:08quickly.

15:09In fact, I already know that there's

15:11another version at the time of this

15:12recording, which

15:13adds a few bits of functionality to Prep.

15:17So it's really, really important to stay in

15:19tune with all the updates so you know what

15:21's

15:21going on.

15:22Wherever possible, I'll try and link the

15:24updates and notification cards in the top

15:27of all the

15:27videos.

15:28So if you see those, tune in.

15:30Otherwise, I'll drop something in the

15:31description linking to where you can find

15:33the latest updates

15:33about Tableau Prep.

15:34All right.

15:35Join us in the next video where we're going

15:37to start talking about our first tool,

15:39which

15:39is the cleansing step, this line step here

15:43that you see me selecting.

15:46If you enjoy the video, hit subscribe.

15:47If not, drop a comment.

15:49Let us know what you'd like to see on the

15:51channel and I'll catch you in the next one.