88.Describe the Tableau Architecture?
Tableau Server has a highly scalable, n-tier client-server architecture that serves mobile clients, web
clients, and desktop-installed software. Each of the components is explained below.
89.Data Layer:
One of the fundamental characteristics of Tableau is that it supports your choice of data architecture.
Tableau does not require your data to be stored in any single system, proprietary or otherwise. Most
organizations have a heterogeneous data environment: data warehouses live alongside databases,
whether on premise or in the cloud. Cubes and flat files like Excel are still very much in use. Tableau can
work with all of these simultaneously.
90.Data Connectors:
Tableau includes over 40 optimized data connectors for data sources such as Microsoft Excel, SQL Server,
Google BigQuery, Amazon Redshift, Oracle, SAP HANA, Salesforce.com, Teradata, Vertica, Cloudera and
Hadoop. There is also a generic ODBC connector for any systems without a native connector.
Tableau provides two modes for interacting with data: live connection or in-memory. Users can switch
between a live and in-memory connection as they choose.
91.Live connection:
Tableau’s data connectors leverage your existing data infrastructure by sending dynamic SQL or MDX
statements directly to the source database rather than importing all the data. This means that if you’ve
invested in a fast, analytics-optimized database like Vertica, you can gain the benefits of that investment
by connecting live to your data. This leaves the detail data in the source system and sends the aggregate
results of queries to Tableau.
92.In-memory:
Tableau offers a fast, 64-bit ready, columnar in-memory Data Engine that is optimized for analytics. You
can connect to your data and then, with one click, extract your data to bring it in-memory to perform
queries in Tableau up to 100x faster. Tableau’s Data Engine fully utilizes your entire system to achieve
fast query response on hundreds of millions of rows of data on commodity hardware.
Tableau Server Main Components:
The work of Tableau Server is handled with the following four server processes:
93.Application Server:
Application Server processes (wgserver.exe) handle content browsing, server administration and
permissions for the Tableau Server web and mobile interfaces. When a user opens a view in a client
device, that user starts a session (workgroup_session_id) on Tableau Server. The default timeout for this
session is easily configuration by an administrator.
94.VizQL Server:
Once the user is authenticated via the application server, the user can open a view. The client sends a
request to the VizQL process (vizqlserver.exe). The VizQL process then sends queries directly to the data
source, returning a result set that is rendered as images and presented to the user. In many cases,
Tableau Server leverages client-side rendering and caching to reduce the load on the server.
95.Data Server:
Unlike traditional approaches to meta data management, the Tableau Data Server is a key component
that allows IT administrators to enable monitoring, meta data management and control for IT, while
enabling self-service analytics for business users. It lets you centrally manage and store Tableau data
sources and provides end users with secure access to trusted data in a self-service analytics deployment.
96.Backgrounder:
The backgrounder refreshes scheduled extracts, delivers notifications and manages other background
tasks. The backgrounder is designed to consume as much CPU as is available so as to finish the
background activity as quickly as possible.
97.Gateway/ Load Balancer:
The Gateway routes requests to other components. Requests that come in from the client first hit an
external load balancer, if one is configured, or the gateway and are routed to the appropriate process. In
the absence of an external load balancer, if multiple processes are configured for any component, the
Gateway will act as a load balancer and distribute the requests to the processes.
98.Clients: Web Browsers and Mobile Apps
Tableau Server provides interactive dashboards to users via zero-footprint HTML5 in a web or mobile
browser, or natively via a mobile app.
99.Tableau Desktop
Tableau Desktop is the rapid-fire business analytics authoring environment used to create and publish
views, reports and dashboards to Tableau Server. Using Tableau Desktop, a report author can connect to
multiple data sources, explore relationships, create dashboards, modify metadata, and finally publish a
completed workbook or data source to Tableau Server
100. What are the different data security levels?
Tableau provides several ways for you to control which users can see which data. For data sources that
connect to live databases, you can also control whether users are prompted to provide database
credentials when they click a published view. The following three options works together to achieve
different results:
Database login account: When you create a data source that connects to a live database, you choose
between authenticating to the database through Windows NT or through the database’s built-in security
mechanism.
Authentication mode: When you publish a data source or a workbook with a live database connection,
you can choose an Authentication mode. Which modes are available depends on what you choose above.
User filters: You can set filters in a workbook or data source that control which data a person sees in a
published view, based on their Tableau Server login account.
101. What is Authentication on Server?
Authorization refers to how and what users are allowed to do with content hosted on Tableau Server
(including projects, sites, workbooks, data sources) after authentication has been verified.
These actions are determined by a combination of the user's site role and permissions associated with
content.
102. What are different site roles we can assign to a user?
Site roles are permission sets that are assigned to a user, such as System Administrator, Publisher, or
Viewer. The site roles define collections of capabilities (delete, save, view, and others) that can be granted
to users or groups on Tableau Server.
- Server Administrator: The server administrator has full access to all servers and site
functionality, all content on the server, and all users.
- Site Administrator: Site administrators can manage groups, projects, workbooks, and data
sources for the site.
- Publisher: Publishers can sign in, interact with published views and publish dashboards to Tableau
server from the desktop.
- Interactor: Interactors can sign in, browse the server, and interact with the published views, but
are not allowed to publish to the server.
- Viewer: Viewers can sign in and see published views on the server but cannot use any interaction
features like filtering and sorting.
- Unlicensed: Unlicensed users cannot sign in to the server. Users are assigned this role when
licenses are not available.
103. What are permissions and how can we set them on various resources?
Permissions determine whether a given user is allowed or denied to perform a specific action on a specific
resource.
There are six areas where permissions can be set:
Site: Sites are at the top of the content hierarchy and provide a way to partition your server into separate
environments for users. Each site is administered separately and has its own Groups, Users, Projects,
Workbooks and Data Sources.
Project: Projects exist within Sites, and are also used to separate content in the server and typically used
to split content into logical groupings, for example around department or function etc.
Group: Groups are collections of Users within a site. They help to organize and manage sets of users for
administration purposes.
User: Users are the individual named users accessing a Site. Every user added to Tableau Server must
have an associated site role. The site role determines the levels of permissions allowed for a user,
including whether a user can publish, interact with, or only view content published to the server.
Workbook: Workbooks use the default permissions from their project. Unless permissions are locked, the
publisher of the dashboard has final control over who sees their data when it is published.
Data Source: Similar to Workbooks, Data Source permissions can be determined by either the Publisher,
if publishing to an unlocked project, or by the project permissions, if publishing a data source to a locked
project.
104. Why do you publish a data sources and workbooks?
Suppose you create a view that exposes a new range of questions in the data you’re using, and you want
to share this analysis with other people using this data. Or maybe you are your team’s Data Steward, in
charge of building the data models approved for use by analysts, and meeting your organization’s
requirements for security, compliance, performance, and so on.
You can share your work with the rest of your team by publishing it to Tableau Server or Tableau Online.
After it’s published, you and your team can access it through your web browser or the Tableau mobile
app. Publishing data sources can also help you to centralize data management.
105. What are the Best Practices for Published Data Sources
Publishing data sources to Tableau Online or Tableau Server is integral to maintaining a single source for
your data. Publishing also enables sharing data among colleagues; including those who don’t use Tableau
Desktop but have permission to edit workbooks in the web editing environment.
Updates to a published data source flow to all connected workbooks, whether the workbooks themselves
are published or not.
106. What makes up a published data source
The data connection information that describes what data you want to bring in to Tableau for analysis.
When you connect to the data in Tableau Desktop, you can create joins, including joins between tables
from different data types. You can rename fields on the Data Source page to be more descriptive for the
people who work with your published data source.
An extract, if you decide to create one. Guidelines for when to create an extract are included below, as
well as in the additional resources.
Information about how to access or refresh the data. The connection also includes access
information.
107. How can you schedule the Reports in tableau?
When you publish workbooks that connect to extracts you can schedule the extracts to be refreshed
automatically. That way you don't have to republish the workbook every time the underlying data is
updated and you can still get the performance of a data extract.
This increases performance and avoids queries to the live database. Then you can add that workbook to a
schedule so that the extract is refreshed at regular intervals with updated data from the data warehouse.
Schedules are created and managed on the server by an administrator. However, an administrator can
allow you to add a workbook to a schedule when you are publishing from Tableau Desktop.
1. As you are publishing a workbook, in the Publish Workbook to Tableau Server dialog box, click
Scheduling & Authentication.
2. In the Scheduling & Authentication dialog box, select a schedule for the workbook:
All data sources that require authentication must have an embedded password so that the extract
can be refreshed. This includes data sources that are not extracts
108. What is Hyper?
Hyper is a high-performance in-memory data engine technology that helps customers analyze large or
complex data sets faster, by efficiently evaluating analytical queries directly in the transactional database.
A core Tableau platform technology, Hyper uses proprietary dynamic code generation and cutting-edge
parallelism techniques to achieve fast performance for extract creation and query execution.
With Hyper, transactions and analytical queries are processed on the same column store, with no postprocessing needed after data ingestion. This reduces stale data and minimizes the connection gap
between specialized systems. Hyper's unique approach allows a true combination of read-and write-heavy
workloads in a single system. This means you can have fast extract creation without sacrificing fast query
performance.
109. What are the performance benefits of Hyper?
Starting in 10.5, Hyper technology is integrated with Tableau Data Engine to give you the following key
benefits:
Faster extract creation: With Hyper technology, extracts are generated almost as fast as the source
system can deliver data, no sorting needed.
Support for larger extracts: Prior to this release, you might have not been able to get all your data into
a single extract. With the new Hyper technology, much larger amounts of data can be included in a single
extract.
Faster analysis of extracts: In many cases you will see faster querying of data for larger extracts, or
workbooks with complex calculations.
Hyper technology is memory-optimized. This means that when needed, all data lives in memory. This
results in fast data access times.
Hyper is a compiling query engine. Queries are either interpreted or compiled to the machine code for
maximum performance and allowing the Data Engine to get most performance out of modern hardware
(CPU, large main-memory capacities).
110. What is VizQL?
At the heart of Tableau is a proprietary technology that makes interactive data visualization an integral
part of understanding data. A traditional analysis tool forces you to analyze data in rows and columns,
choose a subset of your data to present, organize that data into a table, then create a chart from that
table.
VizQL skips those steps and creates a visual representation of your data right away, giving you visual
feedback as you analyze. As a result, you get a much deeper understanding of your data and can work
much faster than conventional methods–up to 100 times faster.
111. Where can we find Tableau Repository?
Tableau Repository will be found under the “Documents”
It contains number of folders.
It will be automatically created while we install Tableau in our system. Those folders contain logs, where
every hit of Tableau will be recorded in the form of logs in the notepad files also it contains some of the
information like map sources, Bookmarks, etc.
112. What is an increment refresh and full refresh?
Incremental refresh and Full refresh are the classification of scheduling. Incremental refresh will refresh
only the incremental records of data during refresh in scheduling whereas the full refresh will refresh the
full data during refresh in scheduling.
Thought process /Client Communication questions:
These questions will be asked to understand how to communicate with clients, how you build and maintain
relations with them.
113. Given a scenario where we have multiple stakeholders for a dashboard, how to you
interact?
If a dashboard has consumers at different levels, example CEO, regional manager, and field staff, I try to
meet and get requirements from them individually given that every individual role will have specific
business questions to answers.
Every role has some specific KPI’s to look at, specific business questions to answer, specific data to
analyze, display and granularity of data detail. There is no one size fits all. It’s a good practice to tailor
dashboards as per client requirements.
114. Do you tend to create multiple variations of the same visualization for different
stakeholders, if yes why and no why, what’s the rationale behind that?
I believe that if we are speaking to everyone, we are not speaking to anyone. There is no solution that fits
everyone’s needs. If you create one dashboard for all the consumers in the company, no one person will
benefit from it.
The solution has to be customized to fit the needs of the consumer. The more we can understand their
needs, the better we can build a solution to solve their problems.
115. How do you enable reports access for both internal and external customers?
We design and use a combination of row level security, custom tables, roles and permissions to enforce
the required security for customers. That will be an architecture and server level discussion we would have
with our internal team, internal and external customers and design a best solution that fits the need.
116. How do you design architecture to be both secure, scalable and robust?
It depends on various factors like the number of users who are going to interact with dashboards, user
roles, user types (both external and internal), the server model (term or perpetual), licensing model (core
based or user based) etc.
117. How do you communicate with stakeholders and how do you form relations?
The key thing here is to understand client’s requirement and make sure we design and build dashboards
to solve the problems. It’s always recommended to keep client’s in the loop of what’s going on in the
project and be up-front if there is any change in the project delivery. Client doesn’t like any last-minute
surprises.
118. How do you set and manage their expectations?
a) Be Honest from the get-go
b) Set goals, and point to these goals during every single conversation
c) Under- Promise and Over-Deliver.
d) Constant Communication
e) Weekly/ fortnightly status reporting.
f) Be transparent about what you can accomplish
g) Be upfront about what happens if plans change
119. How do you capture requirements?
We capture dashboard/report requirements in a business specifications document, technical specifications
document (high level and low level), wireframe, storyboard, user stories etc. You can read more
120. How do you capture business questions, what to be solved?
Those can be captured as user stories. Each business question that needs to be answered is captured here
which forms as a foundation for dashboard design and building.
121. How do you communicate with clients when there is delay or issue that impacts delivery?
It is highly recommended and I follow swift communicate with the clients as soon as I have visibility of the
change or slip in the schedule. This ensures both of us are on the same page and client can make
changes/ inform their customers in case of any business impact.
122. How do you convince and make clients understand about technical stuff or benefits of a
particular design choice?
I always show them visually by creating a quick proof of concept and explaining the benefits of a new
approach if that is the way to go.
123. How do you roll out delivery across the whole organization?
We identify a few power users who understand the business well and showcase and train them first to
make sure they understand the benefit. Once they are comfortable with the solution, they can help the
people in the field in their respective regions to adopt the solution. We also identify and release the
solution phase wise so it is easy for us to support new requests and user questions if any.
124. Is documentation process important in the project?
Yes, it is absolutely necessary to have proper documentation for a few reasons below.
A. It will be easy for other/new team members to pick up the report and make changes if needed.
B. This serves as a document for auditing and change control purpose.
C. This can be used to refer when impact analysis of a new change (adding a new field, removing,
changing etc.) is raised.
It’s wise to use tools that document the workbooks saving a lot of resource time and more efficient in
capturing all the details.
125. How do you make sure the branding is consistent throughout the delivery?
We follow the company specifications including logo, colors, formatting, font and any other branding
materials to make sure the dashboards are all consistent across the board. We try to specify everything in
a document for everyone to follow.
126. How do you communicate with stakeholders during the design and building of
dashboards?
We usually have a weekly showcase with the stakeholders and the team to present the report, brainstorm,
seek feedback and iterate the changes to make sure we are on the right path.
127. What is the difference between showing data and storytelling data?
Showing data is all about presenting data as a self-serve analytics dashboard for users to explore and find
answers. Here we are not presenting any key takeaways for action, but giving them the power to analyze
data.
Storytelling the data is about we, analysts doing exploratory analysis to find story in the data and
presenting the facts to the stakeholders to understand quickly and easily that prompts an action for them
to make a better decision.
128. Did you maintain server administration, users?
Yes, I did maintain tasks server administration to perform tasks such as but not limited to adding new
users, maintaining users, Active directory configuration, SSO, licensing, creating and modifying schedules,
installation of new server instances.
129. Did you ever lost your hold on best practices and compromised to follow what client
says?
Sometimes we have to follow what client insist regardless of they are standard data visualizations or not.
It’s common. We try to explain them the pros and cons of the process, but it is up to their decision to tell
us what to follow.
130. Did you ever receive any out of the report requests and how did you prioritize?
We do receive ad hoc reporting requests from various teams time to time. We do receive, we will politely
ask them to route them through our manager so he/she can assign the work based on priorities.
131. What 3rd party tools have you used in the Tableau/Data visualization project?
We used:
Rapidox for workbook documentation.
Tabjolt for load testing
Powertools for Performance tuning and best practices.
Tabmon for Performance monitoring.
Tabmigarte to migrate data between multiple environments.
