Intermediate Level

Differentiate parameters and filters in Tableau

Filters are the simpler and straightforward feature in Tableau. It applies
to dimensions or measures directly. For example, to only show Gujarat
or Karnataka in a State dimension, we can apply the filter on that. In
Tableau, there are multiple UI options available for filters like radio
buttons, drop-down lists, checkboxes, sliders, and more. Filters on sheets
are also available in Tableau.

Parameters are like variables. They are complex and more powerful.
Like a variable, a parameter can be used in calculations. So, that means, it
only allows a single value. Parameters have the same UI options except
for checkboxes because checkboxes don’t have a single value. For
example, we can create a parameter for interest rate and period, and then we can use these parameters to calculate interest and principal
payments.

Explain how many types of filters are available in Tableau?

Filters are used to provide the correct information to viewers after
removing unnecessary data. There are various types of filters available in
Tableau.
Extract Filters - Extract filters are used to apply filters on extracted
data from the data source. For this filter, data is extracted from the data
source and placed into the Tableau data repository.
Datasource Filters – Datasource filters are the same as extract filters.
They also work on the extracted dataset. But, the only difference is it
works with both live and extract connections.
Context Filters – Context Filters are applied on the data rows before any
other filters. They are limited to views, but they can be applied on
selected sheets. They define Aggregation and Disaggregation of data in
Tableau
Dimension Filters – Dimension filters are used to apply filters on
dimensions in worksheets. Dimension filters are applied through the top
or bottom conditions, formula, and wildcard match.
Measure Filters – Measure filters are applied to the values present in
the measures.

Differentiate between Tiled and Floating in dashboards?

In a tiled layout, items don’t overlap. The layout will be adjusted
according to dashboard size. In the floating layout, items can be placed
on some other layers. Floating items can have fixed positions and sizes.

Categorize dimensions in Tableau?

Dimensions are divided into 9 various categories

Slowly ever-changing dimension: The value of the dimension changes
over an amount of time for slowly ever-changing dimensions.
Example – student of worker
Chop-chop ever-changing Dimension: Value in the dimension is rapidly
changing for chop-chop ever-changing dimensions.
Example – Age (It changes every second)
Unchanged Dimension: Values are constant for unchanged dimensions.
Example – Traffic Signals
Shrunken Dimension: A set of 1 dimension is termed as Shrunken
Dimension.
Example – A week is Shrunken dimension for the month
Junk Dimension: Junk values or unrelated dimensions are termed as
Junk Dimension.

Conformed Dimension: If any dimension is provided by various
business areas, then such a dimension is termed as Conformed
Dimension.
Example – Time (9-5) for any company or hospital or college
Degenerated Dimension: Degenerated dimensions have primary keys
only without any matter of info.
Role enjoying Dimension: If one dimension is employed in multiple
roles, then they are termed as Role enjoying Dimensions.
Example – Date for e-commerce site order (Date of Order, Date of
Shipment, Date of delivery)
Inferred Dimension: Empty dimensions are called inferred dimensions.
They are usually used in ETL.
Example – Customer email which he may not enter while submitting any
form will be filled as null.

What is VIZQL in Tableau?

VIZQL is Visual Inquiry Language. It is a combination of VIZ and SQL. It is
similar to SQL language. But instead of SQL commands, the VIZQL
language converts data queries into visual images.

Explain the disaggregation and aggregation of data in Tableau?

Aggregation → The process of summarizing the data and viewing a
single numeric value is called aggregation. Example – sum/avg of salary
for each employee

Disaggregation → The process of viewing each transaction for analyzing
all the measures both dependently and independently. Example –
individual salary transactions for each employee.

State the components of the dashboard?

The dashboard consists of 5 components.
• Web: it consists of a web page embedded in the dashboard.
• Horizontal component: it is a horizontal layout container in
which we can add objects.
• Vertical component: it is a vertical layout container in which we
can add objects.
• Image Extract: it allows you to upload an image to the dashboard
from a computer.
• Text: it is a small Wordpad where we can format and edit the text.

Differentiate discrete and continuous data roles in Tableau

• Discrete data roles consist of values that are separate and distinct.
Discrete data roles can take individual values within a range. For
Example – cancer patients in the hospital, no. of threads in a sheet,
state. Discrete values are displayed as blue icons in the data
window and blue pills on shelves. Discrete fields can be sorted.
• Continuous data roles consist of any value within the finite or
infinite intervals. For Example – age, unit price, order quantity.
Continuous values displayed as green icons in the data window and
green pills on shelves. Continuous fields cannot be sorted.

What is the difference between Traditional BI Tools and Tableau?

Traditional BI Tableau BI Architecture has hardware limitations. Tableau
does not have dependencies. It does not support in-memory, multi-thread, and multi-core computing. It supports memory when using
advanced technologies. It has a predefined view of data. It uses
predictive analysis for various business operations. We should need a
good knowledge of BI and skills. It is easy working and understanding
without the knowledge of BI and the skills data security is provided data
security is not provided for the public, whereas in the professional
version.

Define performance testing in terms of Tableau

• We can create performance recordings to keep track of
performance details of main events while interacting with
workbooks. Then, these performance metrics can be viewed by the
user and analyzed. Navigation to start/stop performance recording
is Help→Settings and Performance>→ Start Performance Recording
Help→ Setting and Performance → Stop Performance Recording
• Review the logs created by Tableau Desktop. The location for log
files is C:UsersMy DocumentsMy Tableau Repository.
• For live connection, check the log files log.txt and tabprotosrv.txt.
• For Extract connection, check the log file tdeserver.txt

What is the difference between .twb and .twbx extensions?

• .twb: .twb means Tableau workbook. .twb is an XML sheet, it stores
the data about your documents, stories, and dashboards. This file is
the reference to the source file such as Excel or tde. This file will be
linked to your source file when you save the TWB file. If you want
to share your workbook you need to send both the workbook and
data source file.

• .twbx: It is a compressed file, where you have all files. It includes
data source files, twb, and other files to produce the workbook.
TWBX is obsolete for sharing because it will share the copy of the
file instead of an original source file. .twbx is used for reports and
we can view using the tableau viewer.

Why Tableau?

• Tableau is very simple and user-friendly.
• Tableau helps in analyzing the data and using this one can change
the raw data into an understandable format.
• Users can blend the data with the other data to create their own
views on the data and to share it with the customers, and
colleagues.
• Users can manage a large amount of data.
• It can easily integrate with multiple data sources.
• Tableau can create complex graphs which simply look like pivot
table graphs in Excel.
• It gives quick calculations on datasets.
• Users can create the visuals easily and switch between the types, to
find the model to represent the user messages.

How to create a calculated field in Tableau?

Step 1: Select Analysis -> drop down will open -> Select create calculated
field.
Step 2: Calculation Editor Box will open, give the name to the calculated
field.
Step 3: Enter a formula in the calculation editor.
Example: Sum(Profits)/Sum(Sales). (Calculation Editor validates the
formula)
Step 4: Click, Ok.
Now, the new calculated field added to the data pane.

Are there any limitations of parameters in Tableau? If yes, give
details.

Tableau dashboard allows the representation of parameters in four ways
only. They don’t allow any multiple values like a filter can do. They only
allow a single value.

State some reasons for the low performance of Tableau? Explain in detail.

Following are the reason for low performance
• Filters - filters need to create an extra query and if it used in large
numbers and inefficiently then they can reduce the performance.
So, it is advised to use filters whenever it is mandatory
• Live connection - Tableau extract works much better in
comparison with a live connection.
• Data sources - a wrong query to a wrong data source can reduce
performance. Also, the data source’s performance can also affect
Tableau’s performance.

State some ways to improve the performance of Tableau.

Following are the few ways to improve the performance
• Use an Extract to make workbooks run faster
• Reduce the scope of data to decrease the volume of data
• Reduce the number of marks on the view to avoid information
overload
• Try to use integers or Booleans in calculations as they are much
faster than strings
• Hide unused fields
• Use Context filters
• Reduce filter usage and use some alternative way to achieve the
same result
• Use indexing in tables and use the same fields for filtering
• Remove unnecessary calculations and sheets

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