Power Pivot: Fetches and cleans data and loads on to Power Query Power Query: Operates
on the loaded data
Power Q&A: Makes it possible
for users to interact with reports using simple English
language
Power View: This lets users create interactive charts, graphs, maps, and other visuals
Power Map: Enables the processing of accurate geographic
locations in datasets
Q2. How Power BI is different
from Tableau?
Ans. Below are some of the major differences between Power BI and Tableau:
Pricing:
Power BI is generally
less expensive than Tableau, especially
for larger teams.
Ease of use:
Power BI is generally
easier to use, especially for those who are already familiar
with Microsoft products. Tableau has a more robust
feature set.
Data sources:
Both Power BI and Tableau
can connect to a wide range of data sources, including
databases, Excel files, and web-based data. However, Tableau has more advanced features for connecting to and preparing data.
Visualizations:
Both Power BI and Tableau offer a wide range of visualization options. However, some users feel that Tableau
offers more flexibility and customization
options, while others prefer the simplicity of Power BI's visuals.
Q3.
How is Power BI different
from other BI tools?
Ans. Power BI provides better
features and data manipulation tools
as compared to other BI
tools like Tableau. A single user can connect
with multiple data sources without any experience in coding and data analytics. As a product of Microsoft,
Power BI is closely integrated with other
Microsoft tools such as Omce 365, SharePoint, and Bing.
In the free version of Power BI Desktop, the user can analyze datasets
of up to 1GB in storage along
with 10,000 rows of data steaming every
hour. Moreover, it provides features like Power Query
which allows the
user to easily visualize the datasets by giving the command in the natural
English language.
Q4. What is Dax Function?
Ans. It is a formula expression language
called (DAX) that can be used with various visualization tools like Power BI. It
is also known as a functional language,
where the full code is kept inside
a function.
Data types of Dax are:
1) Numeric, 2) Boolean, 3) Date Time, 4) String,
and 5) Decimal.
Q5. What are the types of fllters available
in Power BI Reports?
Ans. Important filters of Power BI reports
are:
Visual-level Filters Page-level Filters
Report-level Filters
Q6.Differentiate between
Power BI and Excel.
Ans. The key differences are:
Tabular reports-
Power
BI is not very good at handling
tabular reports. Excel is better at handling
tabular reports.
Duplicate table-
Power BI can’t display
duplicate tables.
Excel allows users
to display duplicate tables.
Reports-
Power BI allows interactive, personalized reports.
Excel users cannot
perform advanced cross-filtering between charts.
Analytics-
Power BI offers simple analytics. Excel
offers advanced analytics.
Applications-
Power BI is ideal for KPIs, alerts, and dashboards.
Excel has new charts now but they can’t connect
to data model.
Q7. What
is the CALCULATE function in DAX?
Ans. The CALCULATE function
helps calculate the sum of an entire
column.
It can be modified using
filters. Syntax:
(CALCULATE(<expression>[, <filter1> [, <filter2> [, …]]]) Expression: The expression that has to be evaluated.
Filter: The filter is a boolean
expression or a table expression that is
supposed to define
a filter.
Q8. What are the different challenges faced by a Power BI developer?
Ans. The challenges faced are:
Power BI does
not have a feature for
data cleansing It will create
problems with large
datasets
Power BI might face performance issues as it has been observed that it cannot process more than 20000-30000 rows without running into issues for some queries
Bulky user interface
Q9. How can you do automation
in Power BI?
Ans. Automation can be done
with Power Automate.
Power
Automate is a cloud-based service
that allows you to create
workflows to automate business processes. With Power Automate, you are able to use out-of-the-box
connectors that allow you to connect
to more than 200 services and automate repetitive tasks, saving you a considerable amount
of time and effort.
Q10. Can you explain the bookmark function
of Power BI?
Ans. If you want to capture a configured view of
your report’s current state, you can
use the bookmark feature to achieve this. Default bookmarks capture specific
elements of your reports, including
slicers and
filters.
Q.11. Explain the major concept of Power BI.
Ans. Power BI is a cloud-based, self-service
business intelligence solution. It is popularly used for data sharing and creating reports
and dashboards.
Power BI is a user-friendly software that offers an attractive graphical user interface with intuitive visualizations.
Business users can collect data from multiple
data sources at a time and work with it to create
reports for analysis.
Power BI has on-premise, web-based, cloud-based as well as mobile platforms to share the reports created for other users. The users with whom you share these
Power BI reports and dashboards can
interact with it by filtering and using slicers
according to their needs.
Q12. What is Power
BI Desktop?
Ans.
Power BI Desktop
is a Microsoft Windows desktop
application for Power BI. It is free-of-cost software
that can be installed on any device like a laptop
or PC. The Power BI Desktop is loaded with tools and capabilities to import, cleanse,
design, and model data. Also, it has
many attractive as well as interactive visualizations to represent data graphically in reports. The Power BI Desktop works in association with the Power BI Service. You can save
the reports/files that you create in Power BI or publish
them on the Power BI Workspace/site or with other business users.
Q13. What is Get Data in Power BI?
Ans. The get Data feature offers data
connectivity to a number of different data sources. The Get Data option is on the Menu bar of the Power BI Desktop main
page. We can click on this option
to connect our Power BI Desktop app with a preferred data source.
You can connect to data files on your local system, Excel files, Azure SQL Database,
Facebook, Google Analytics, Power BI datasets,
etc.
Q14. What are the building
blocks of Power BI?
Ans. Power BI consists of some key components that can also be called
its building blocks.
Five key components
of Power BI are the Visualizations, Datasets,
Reports, Dashboards, and Tiles.
Q15. What are the visualizations in Power BI?
Ans. Visualizations are the visual representation
of data. Power BI offers a wide range
of attractive visualizations. We can create reports and dashboards using both simple
as well as complex visualizations to represent the data set.
There is also a
library available for custom visualizations. We can format and customize the visualizations as per liking
and edit every
detail from the appearance to the data labels finely.
In Power BI, we can create visualizations such as, Bar charts, Column
charts, Line
chart, Area chart,
Pie chart, Stacked
area chart, Ribbon
chart, Waterfall chart,
etc.
Q16. What are reports
in Power BI?
Ans. Reports in Power BI are a combination and collection of different kinds of visualizations relevant to a particular business
topic. A report
is a graphical and structured presentation of datasets used in the analysis. They are informative and reveal
important insights from the data.
Users can easily share and publish
reports created in Power BI with other
users via Power BI Desktop and Power BI website,
cloud-based platforms and mobile platforms.
Q17. What do you understand by dashboards in Power BI?
Ans. A Power BI dashboard
is a canvas on which we can bring together
different elements
or visualizations to represent datasets. A dashboard gives us a graphical overview
of the story that lies in the
detailed BI report. It contains all the important
elements from a report.
A dashboard is always a single page. The
consumers use the dashboard for analytical purposes
like getting a quick insight
into their business, making
an important decision based on the information given on a dashboard, etc.
Q18. What are the KPIs in Power BI?
Ans. KPIs are the Key Performance
Indicators. The KPIs evaluates an organization’s performance in different areas by evaluating values and measurable goals. A KPI always has a base value or measure which is evaluated
against a target
value. You can evaluate the performances in an analysis just by seeing the KPI as they graphically represent the evaluation. Thus, KPIs will show whether the goals you have set are met or not.
Q19.How many versions of Power BI are available as of
now? How are they different?
Ans. There are presently three versions or editions of Power
BI i.e. Power BI Desktop,
Power BI Pro and Power BI Premium.
Power BI Desktop: Power BI Desktop is a free of cost development, authoring
and publishing tool of Microsoft Power BI. It is a user interaction platform from where users can connect
to multiple data sources, transform and clean data,
visualize and create reports.
Power BI Pro: Power BI Pro is a modern self-service BI having advanced features for collaboration, publishing, report sharing, and ad hoc analysis. It costs $9.99 per month per user.
Power BI Premium: Power BI Premium is an enterprise BI solution with features and tools for advanced analytics, big data support, on-premises and cloud reporting, etc. It
also provides dedicated cloud
computing and storage facilities. It costs $ 20 per month per user.
Q20. What are Slicers
in Power BI?
Ans. Slicers in Power BI are visual
filters that are present in the report
page. The slicers
let us sort and filter information on a packed
report. Unlike filters,
slicers are present
as a visual on the report and we can select values
on it while we are analyzing the data in the report.
For example, if we have a sales analysis report, you can make a slicer for years. From that slicer,
we can select the year for which we want to see the sales metrics such as 2017, 2018 etc. The
report visuals will automatically and instantly change to
show the information for the selected year.
Q21. Discuss
about the Content
Packs in Power BI.
Ans. The Power BI content
packs are packages
or pre-build solutions
that contain several
Power BI objects such as reports, dashboards,
datasets, Excel workbooks, etc. A user can deploy
their data/objects to the content packs and share them with
others in an organization. Content
packs are shared and accessed via the Power BI site (Workspace).
There
are two types
of content packs;
the service provider
content packs and user-created content
packs.
Q22. What are Custom
visuals in Power
BI?
Ans. Custom visuals
are customized visualizations like charts, KPIs, etc. that are created by developers from scratch using custom visuals
SDK. Power BI offers a rich library of custom visuals which you can select, import and use in your Power BI
report. Developers use JavaScript libraries such as jQuery, D3,
R-language scripts, etc. to create custom visuals.
Q23. What
data sources can you connect to Power BI?
Ans. The Power BI data sources
are divided as follows:
Files: Data can be imported from Power BI Desktop files (.pbix), Excel (.xlsx, xlxm),
and Comma Separated Value (.csv).
Content Packs: It refers to the collection of related files or documents that are stored as a group.
There are two types of content packs in Power BI: those from service
providers including Google
Analytics, Salesforce, and those
created and shared by other users in the organization.
Connectors: To connect databases and other
datasets, including Database, Azure SQL, and SQL Server Analysis Services tabular data, etc.
Q24.How are a Power BI dashboard and a report different from each other?
Ans. Differences are :
1.
Number of pages
Dashboard - Consists of one page only. Report - Can be of one or more pages.
2.
Data sources
Dashboard - Can have data tiles from one or more datasets or reports.
Report - It has a single dataset
per report.
3.
Filtering
Dashboard - Cannot perform filtering or
slicing. Report - Can perform
filtering, slicing and highlighting.
4. Set alerts
Dashboard - Enables you to set alerts for emails. Report - No option for setting alerts.
5.
Accessing dataset
Dashboard - Does not allow viewing or accessing underlying datasets tables
and fields.
Report - Provides
the option for viewing dataset
tables, fields and values.
Q25. What is Power Pivot ?
Ans. Power Pivot is an
in-memory component that enables storing compressed data. It is used to build data models, relationships, create formulas, calculate columns from different
resources.
Q26. What is Power
View?
Ans.
Power View is a data visualization technology, which lets you create interactive graphs, charts, maps,
and other visuals to bring life to your data. It is available in Excel,
SQL Server, SharePoint, and Power BI.
Q27. Deflne Power Query?
Ans. Power Query is an ETL tool to clean, shape, and transform data without any code using
intuitive interfaces. With this:
You can import data from various sources
like databases from files Append
and join data from a wide range of sources
You can shape data as needed by adding and removing it
Q28. What is the major difference
between a Filter and a Slicer?
Ans. Using Normal
filters users are not allowed
to interact with dashboards
or reports, but using slicers we can interact with dashboards and reports.
Q29. What is the Power BI Service?
Ans. Power BI Service is a cloud-based
analytics solution that helps you to create dashboards and publish, design
reports, collaborate and share the reports with internal and external stakeholders.
Q30. Tell us about the Excel add-ins for Power BI.
Ans. The Excel BI Toolkit for Microsoft self-service BI has got a number of add-ins:
Power Query for data mash-up
and transformation. Power
View for viewing
data visualizations.
Power Pivot for in-memory tabular
data modeling. Power
Map for visualizing 3D geo-spatial data.
Q 31. Share some key points
about DAX usage
in Power BI?
Ans. Some key points about DAX:
DAX is a functional language.
So its complete code is always a function.
An executable DAX expression generally contains conditional statements, nested functions, value references, etc.
DAX formulas have two primary
data types- Numeric
and Non- numeric.
The numeric data type includes integers, decimals, currency, etc. And, the non-numeric consists of strings
and binary objects.
DAX expressions are evaluated in an inward
to outward fashion.
It starts from the innermost
function going to the
outermost function at the last.
We can use values of mixed data types as inputs in a DAX formula.
Q32. Which table functions
will you use to group data in Power BI?
Ans. We can use two main DAX functions to group data in Power BI - SUMMARIZE() and SUMMARIZECOLUMNS:
The SUMMARIZE function is used to group data by columns.
The SUMMARIZECOLUMNS function is generally used in Power
BI to group data by columns,
expressions, and tables.
Q33. Explain
the concept of Power BI DAX?
Ans. The three fundamental concepts
of Power BI DAX are Syntax, Context, and Functions.
1.
Syntax:
It comprises of various components that make up the formula.
For
e.g. - Total Sales = SUM(Sales[SalesAmount])
Total Sales is the Measure
name.
The equals sign
(=) indicates the start of the DAX formula. SUM is used to add the values of a given field.
The parenthesis () is used to enclose and define arguments in an expression
Sales are the table referenced
The referenced column
[SalesAmount] is an argument with which the SUM function identifies the column on
which it has to aggregate a SUM.
2.
Context:
It is one of the essential concepts
of DAX. There are two types of Contexts - Row Context
and Filter Context.
The Row-Context is applied whenever
a formula has a function
that filters
to identify a single row in a table.
Filter-Context is used when one or more filters are applied in a calculation.
3.
Functions:
Functions are structured, predefined, and ordered formulae.
They complete calculations using arguments passed
on to them.
Q34. Explain some commonly
used DAX functions.
Ans. Some of the most commonly used DAX functions are: Date and Time Functions
-
These
functions carry out calculations on the date and time values. Ex: DATE, CALENDER, HOUR, MINUTE
Time Intelligence Functions -
These functions are used to evaluate values over a fixed period.
Ex: DATESBETWEEN, ENDOFQUARTER, CLOSINGBALANCEMONTH
Logical Functions -
These functions are used to evaluate an argument or expression logically. Ex: AND, FALSE, IFERROR,
IF
Mathematical and Trigonometric Functions -
These functions are used to perform
all sorts of mathematical functions on the reference values.
Ex: DIVIDE, FACT, ACOS
Statistical Functions -
These
functions carry out statistical and aggregation functions on data values in a DAX expression. Ex: AVERAGE, COUNT, GENERATE
Text Functions -
These are similar to the string
functions of Excel. Ex: FIND, LEFT, FIXED, FORMAT
Table functions -
In DAX formulas, these functions are used to apply operations and conditions on entire tables.
Ex: FILTER, VALUES,
DISTINCT
Q35. What is a summarize function
in DAX?
Ans. Summarize is a DAX function that gives an aggregated result from a table. This is how summarize function
is used:
Summarize(<table>,<grouping column>,[<name>,<expression>)
table - a DAX expression that returns a table
grouping column - the column
name you want to use for grouping
name - the name of the new aggregated column
expression - generates
the aggregated column.
Q36. What are DAX Calculation types?
Ans.
DAX in Power BI has two types of calculations or formulas. These are:
Calculated Columns: These are used to merge new columns into existing ones with filters. These columns can be created
from the Modeling tab in Power BI Desktop, where
new columns can be created by entering their names and formula.
Calculated Measures: They enable the user to create
fields with aggregate values like average, ratio,
percentage, etc. The measures are also created from the modeling
tab of Power BI Desktop.
Q37. Explain Power BI Query Editor.
Ans. Power BI Query Editor is used to
transform or edit data files before
they are loaded. The Query Editor plays the role of an intermediate data container where you can transform data by selecting
rows and columns,
splitting rows and columns, pivoting
and unpivoting columns, etc.
The modifications done by the Query
Editor are not reflected in the actual
datasheet.
Q38. Are Power View and Power Query the same?
Ans. Power Query can be used to download data to Excel as well as make nice transformations. Example: Filter, merge multiple sources,
calculate, etc.
Power View enables
you to present the data in reports.
Q39. What is
parameter in Power BI?
Ans. A parameter serves as a way to
easily store and manage a value that can be reused. Parameters give you the flexibility to dynamically change
the output of your queries
depending on their
value. And can be
used for Changing the argument values for particular transforms and data source
functions.
Q40. How to sort data in Power BI?
Ans. Sorting is available in multiple formats.
In the data view, there is a common
sorting option of alphabetical order.
We have the option of Sorting by column,
where one can sort a column based
on another column.
Sort by ascending and descending option by the fields and measure present
in the visual is also available.
Q41. How to combine two columns in Power BI?
Ans. To combine two columns in Power BI, you need to select a new calculated column using the DAX expression.
For example, if you need to add the values of two columns & make the third
column, then you can do it by the Following DAX Expression: Total=Sheet Name(Col1) +sheet Name(Col2).
Q42. What is Power BI Data Gateway? How can we use it?
Ans. Power BI Data Gateway is software used to access the data connected to a premise- network
from the cloud.
On-premises data gateway acts as a
bridge to provide quick and secure data transfer between
on-premises data (data that isn't
in the cloud) and several Microsoft cloud services. These cloud
services include Power BI, PowerApps, Power Automate, Azure
Analysis Services etc.
To use Data Gateway, you need first to
install it in your system; add the
users to this who will be accessing the data from on-premise sources.
Give authentication & request and get connected
to the On- Premise
Data sources.
Q43.How is the fllter function used in Power BI?
Ans. You can use FILTER to reduce the number of rows in the table
that you are working with, and use only specific
data in calculations.
FILTER is not used independently, but
as a function that is embedded in other functions that require a table as an argument.
Power BI Service (Basic to Intermediate Level).
Some Additional Questions.
Q: What is Power BI Service, and how does it differ
from Power BI Desktop?
A: Power BI Service is a cloud-based analytics
platform, while Power BI Desktop is a local data preparation and reporting
tool.
Q: How can you share a Power BI report with others
using the Power BI Service?
A: You can share reports by publishing them to a
workspace, and setting permissions for users or groups.
Q: What are Workspaces in Power BI Service, and how are
they used?
A: Workspaces are collaborative environments in Power
BI Service, where teams can create, edit, and share reports and dash
Q: Explain the role of Row-Level Security (RLS) in
Power BI Service.
A: RLS restricts data access for specific users based
on assigned roles, ensuring data confidentiality within shared reports.
Q: What is the purpose of Dataflows in Power BI
Service?
A: Dataflows allow users to prepare and manage data
within Power BI Service for reuse across reports.
Q: Describe the types of licenses available for Power
BI Service.
A: Power BI offers Free, Pro, and Premium licenses,
each with different levels of sharing and collaboration capabilities.
Q: How do scheduled data refreshes work in Power BI
Service?
A: Scheduled refreshes allow users to automatically
update data at specified intervals, ensuring current information.
Q: What are dashboards in Power BI Service, and how are
they created?
A: Dashboards are single-page summaries of report
visuals created by pinning elements from various reports.
Q: How can you collaborate on reports and dashboards
within Power BI Service?
A: You can collaborate by sharing dashboards, adding
comments, and using workspaces for teamwork.
Q: What are Content Packs, and how do they function
within Power BI Service?
A: Content
Packs are pre-built collections of reports, datasets, and dashboards, which can
be shared with other users. Power BI
Mobile Apps
Q:
How can you interact with reports and dashboards on Power BI Mobile Apps?
A: Power BI Mobile Apps allow you to view, filter, and
interact with data reports and dashboards on mobile devices.
Q: Describe the offline capabilities of Power BI Mobile
Apps.
A: Power BI Mobile Apps support offline access to
cached reports, enabling data review without an internet connection.
Practical Power BI Questions for Newbies
Q: How would you optimize a slow report in Power BI
Service?
A: To optimize, reduce the dataset size, use data
aggregations, limit visuals, and optimize DAX calculations.
Q: How do you handle data refresh errors in Power BI?
A: Start by checking your data gateway and data source
connection, then verify the refresh schedule and any applied credenti
Q: What steps would you take to set up Row-Level
Security (RLS) in Power BI?
A: Define roles with DAX filters in Power BI Desktop,
assign users to roles, and publish to Power BI Service for secure data ac
Q: How can you improve the performance of DAX
calculations?
A: Use calculated columns wisely, avoid complex
measures in visuals, and use variables to simplify DAX expressions.
Q: How do you troubleshoot visualizations that are not
displaying correctly?
A: Check the data model, filters applied, and any
relationships between tables; ensure visuals are properly configured.
Reviewed by Nitesh Kumar Khichi
on
November 10, 2024
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