Intermediate Level

Can we see SQL generated by Tableau Desktop?

Tableau Desktop Log files are placed in C: UsersMy DocumentsMy
Tableau Repository. In case of live connection to any data source, check
the log file “log.txt” and “tabprotosrv.txt” files. In case of extract
connection to any data source, check the “tdeserver.txt” file which has
detailed information about queries.

If the owner of the published workbook license expires, then can other users see those workbooks?

If the owner of a published workbooks license expires then his/her role
will change to “Unlicensed”. He/She cannot access those workbooks, but
others can. Only site admin can change the ownership of those
workbooks

Can we remove the All options from a Tableau auto-filter?

Follow few steps
1. Go to the Segment filter, Click on the small drop arrow which is on
the right side.
2. Select Customize.
3. Then we can visible a small dropbox under customize, uncheck the
option for “ All” Value.

Which one is better? Extract or Live connection?

Extract connection is better than live connection because extract
connection can be used from anywhere, anytime without connecting to
the database. We can construct our own visualizations on it irrespective
of the database connection.

Tell me something about the workbook version controlled in
Tableau.

Versioning of workbooks can be done in 2 ways in Tableau.
• At the desktop level, you keep copies of your changes and files or
using 3rd party system like Microsoft TFS.
• At the server level, where you publish the data source and version
will be saved in revision history on Tableau Server or Online.
Reverting to a previous version is also possible here.

Where can we apply global filters?

Global filters can be applied to sheets, stories, and dashboards.

How to add custom color to Tableau?

To add custom color in Tableau, we need to follow 3 steps
• Generate custom color code and create it in “Preferences.tps”
• Navigate to Documents→ My Table Repository→ Preferences.tps
• Add a note for custom color code

Can we create cascading filters without using context filters?

Cascading filters means filter2 values are dependent on filter1 values.
For Example, filter1 is country and if we select “India” for filter1, filter2
values should show all Indian states. This feature we can achieve by
using the option “Only Relevant Values”.

How can we display the top and bottom 5 of records in a single
Tableau view?

To achieve this, we need to create 2 views
• View1 which contains the top 5 records
• View2 which contains the bottom 5 records
• View3 which is a join of View1 and View2

State a few charts which we should not use with valid reasons

Below here are few charts which we should avoid.
• 3D Charts: Visual representation of numbers in 3D charts will be
skewed and it makes it difficult to compare and analyze.
• Pie Charts: Pie charts are not that much accurate as bar charts. In
Pie charts, we have areas and angles to compare instead of length
in a bar chart. Areas and angles cannot be analyzed with ease.
• Donut Charts: This is the same as Pie chart, but here, we have a
hole in the middle to make it look like a donut. Due to that hole, we
need to compare arc length with other arcs to analyze the values.
Comparing arcs lengths is also a difficult task for our eyes.

Do we have any way to handle null values in Tableau?

Tableau cannot plot null values on-axis. So, it will display an indicator at
the lower right corner of the view. Once you click on that indicator, you
have options to handle null values. Below are the options available to
handle null values.
• Filter Data – If you choose this option, null values will be filtered
out from the view.
• Show Data at Default Position – It replaces the null value with the
default value and shows the data at the default position on-axis.
These default values depend on the data type of field. Below here
are the defaults of a specific data type.
• Numbers →0
• Dates → 12-31-1899
• Geographic Location → (0,0)
• Negative Values → 1

Do we have any data limitations in Tableau Public?

Yes, Tableau Public can only allow 10 million rows to users for data
visualization.

Can we download views or workbooks from the server? If yes, in
which data formats?

We can download views or workbooks from the server. But, data formats
available to us depend on the permissions granted by site administrators
or content owners.
• Image: .png format
• Data: .csv file.
We can also download selected sheets into PDF format, but while
generating PDF, web page objects won’t be included.

Can we use unused columns (Columns that are not used in reports
but data source has columns) in Tableau Filters?

Yes, we can use unused columns in tableau filters.
Let us consider one example.
In data source, I have column like emp_id, emp_name, emp_sal, emp_dep,
emp_designation. But, in reports, I am using emp_name in columns and
emp-sal in rows. I can use emp_designation on filters.

What is the benefit of the Tableau extract file over the live
connection?

Extract files can be used without any connections and you can build your
own visualization without connecting to the database.

How many tables join are possible in Tableau?

We can join 32 tables in Tableau.

Can we place an excel file in a shared location and use it to develop a report and refresh it in regular intervals?

Yes, we can place an excel file in a shared location and we can use it to
develop a report, but for better performance, we need to extract the file.

How do we do testing in Tableau?

Yes, we can do testing in Tableau by using tools and the easiest way is
using the desktop application. We need to check it before we publish it
on the Tableau server.

Can you get values from two different sources as a single input into a parameter?

Tableau, currently not supporting the multi-valued parameters. As
Tableau parameters are not dynamic, we cannot filter the list of values at
runtime.

Design a view in a map such that if a user selects any state the cities under that state have to show profit and sales.

If you want to show the profit and sales of each and every city under the
state in the same worksheet, then follow a few steps.
The data which you want to display under the state, it must be in the
same worksheet.
• Double click on the state filed.
• Drag the city and drop it under the state(Mark Card).
• Drag the Sales and drop into the size.
• Drag the Profit and drop it into the color.
• Click on the size legend and increase the size (75%).
• Give a right-click on State filed and select show filter.
• Select the state and check whether you got the required view or
not.
In the View, Size indicates the Sales, and Color indicates the profit of the
respective state(which you have selected).

How can u set permissions or protect the data in tableau public?

Tableau does not have any security permissions or to protect the data in
Tableau public. Whatever we shared in Tableau public those files,
workbooks can be viewed by all users. There is no security option in
Tableau public.

If I delete a workbook from tableau public and there are links to
other blogs and other web locations. What happens to them?

Tableau public is like a repository, if you delete anything in the Tableau
public the data will be lost, even if links are in other locations and blogs.
We cannot access those links.

Mention whether you can create relational joins in Tableau without creating a new table?

Yes, we can create relational joins in Tableau without creating a new
table.

When publishing workbooks on Tableau online, sometimes an
error about needing to extract appears. Why does it happen
occasionally?

It happens when the user is trying to publish the workbook which is
connected to the internal or local server that means the company’s
network.

Can parameters have a drop-down list?

Yes, Parameters have their own drop-down list, which enables the users
to view the data entries which are available in the parameter during the
creation.

How do you optimize the performance of the dashboard?

1. Minimize the number of fields.
2. Minimize the number of records.
3. Reduce the marks (data points) in your view( remove unneeded
dimensions).
4. Reduce the number of filters.
5. Use an include filter.
6. Use a continuous data filter.
7. Use action filters and parameters.
8. Reduce the number of nested calculations.
9. Remove custom SQL.
10. Clean up your workbooks.

How to use group in calculations field?

Option 1:
We can create the group by using the calculated field.
• Step 1: Select Analysis-> click the calculated field
• Step 2: Enter the field name (a dialogue box will appear)
• Step 3: Enter the calculation -> Click Ok.
Example:
IF [Container]=’Jumbo Box’ then ‘Big Containers’
ELSEIF [Container]=’Jumbo Drum’ then ‘Big Containers’
ELSEIF [Container]=’Large Box’ then ‘Big Containers’
ELSEIF [Container]=’Medium Box’ then ‘Midsize Containers’
ELSEIF [Container]=’Wrap Bag’ then ‘Midsize Containers’
ELSEIF [Container]=’Small Box’ then ‘Little Containers’
ELSEIF [Container]=’Small Pack’ then ‘Little Containers’
END
The above calculation creates the group with four values: Little
Containers, Big Containers, Small Containers, Midsize Containers.
Option 2:
Create a set from the group, and use the set in the calculated field.
Step 1: Right-click on the Data Pane and then select Create Set.
Step 2: Create a set dialogue box that will open,
Enter the field name.
Select the group, on the general tab.
Step 3: Click Ok.

Can Tableau be installed on macOS?

Yes, Tableau can be installed on both the Windows Operating system and
macOS.

How to automate reports in Tableau?

When we are publishing the reports to Tableau Server, there we will find
an option to schedule the report, just select the time when you want to
refresh the data.

Which databases give the best performance when connected live?

Native Database gives the best performance when connected live.

What are the challenges faced when working with huge volumes of
data?

1. View running will be slow.
2. Data Extraction.
3. Alignment issues with data.
4. Testing Data.

State limitation of context filters in Tableau

Whenever we set a context filter, Tableau generates a temp table that
needs to refresh each and every time the view is triggered. So, if the
context filter will be changed, the database needs to recompute and
rewrite the temp table, which in turn slows down the performance.

What is a marks card in Tableau?

There is a card to the left of the view where we can drag fields and
control mark properties like color, size, type, shape, detail, label, and
tooltip.

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