Power BI & Tableau

Which language is used in Power Query?

A new programming language is used in power query called M-Code. It is easy to use and similar to other languages. M-code is case sensitive language.

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

A .twb is an xml document which contains all the selections and layout made you have made in your Tableau workbook. It does not contain any data. A .twbx is a 'zipped' archive containing a .twb and any external files such as extracts and background images.

What are groups?

A group is a combination of dimension members that make higher level categories. For example, if you are working with a view that shows average test scores by major, you may want to group certain majors together to create major categories

What is the difference between a tree map and heat map?

A heat map can be used for comparing categories with color and size. With heat maps, you can compare two different measures together. A tree map also does the same except it is considered a very powerful visualization as it can be used for illustrating hierarchical data and part-to-whole relationships.

What is a hierarchical field?

A hierarchical field in tableau is used for drilling down data. It means viewing your data in a more granular level.

What are Building Blocks in Power BI?

Visualizations: Datasets: Reports: Dashboards: Tiles:

What are the different connections you can make with your dataset?

We can either connect live to our data set or extract data onto Tableau.

What are some benefits of using Variables in DAX ?

By declaring and evaluating a variable, the variable can be reused multiple times in a DAX expression, thus avoiding additional queries of the source database. Variables can make DAX expressions more intuitive/logical to interpret. Variables are only scoped to their measure or query, they cannot be shared among measures, queries or be defined at the model level.

What are some of differences in data modeling between Power BI Desktop and Power Pivot for Excel?

Here are some of the differences: Power BI Desktop supports bi-directional cross filtering relationships, security, calculated tables, and Direct Query options. Power Pivot for Excel has single direction (one to many) relationships, calculated columns only, and supports import mode only. Security roles cannot be defined in Power Pivot for Excel.

What are the different Tableau Products and what is the latest version of Tableau?

Here is the Tableau Product family.

Tableau Server:

It is more of an enterprise level Tableau software. You can publish dashboards with Tableau Desktop and share them throughout the organization with web-based Tableau server. It leverages fast databases through live connections.

Power BI

It is the online solution that enables you to share the interactive reports and queries that you have created using the Excel BI Toolkit.

Tableau Reader:

It's a free desktop application that enables you to open and view visualizations that are built in Tableau Desktop. You can filter, drill down data but you cannot edit or perform any kind of interactions.

What is Tableau Data Engine?

Tableau Data Engine is a really cool feature in Tableau. Its an analytical database designed to achieve instant query response, predictive performance, integrate seamlessly into existing data infrastructure and is not limited to load entire data sets into memory. If you work with a large amount of data, it does takes some time to import, create indexes and sort data but after that everything speeds up. Tableau Data Engine is not really in-memory technology. The data is stored in disk after it is imported and the RAM is hardly utilized.

What is TDE file?

TDE is a Tableau desktop file that contains a .tde extension. It refers to the file that contains data extracted from external sources like MS Excel, MS Access or CSV file. There are two aspects of TDE design that make them ideal for supporting analytics and data discovery. Firstly, TDE is a columnar store. The second is how they are structured which impacts how they are loaded into memory and used by Tableau. This is an important aspect of how TDEs are "architecture aware". Architecture-awareness means that TDEs use all parts of your computer memory, from RAM to hard disk, and put each part to work what best fits its characteristics.

Limitations: Filter parameters can only operate on a single column at a time. (TRUE OR FALSE)

TRUE

What are the different datatypes in Tableau?

Tableau Desktop:

TRUE OR FALSE The filter is not saved as part of the report. Whenever you open a report, you can begin to play with visual filters but there is no way to store the filter in the saved report.

TRUE

TRUE OR FALSE: DAX works on column values.

TRUE

TRUE OR FALSE: We can create calculated column and measures with DAX but we can not calculate rows using DAX.

TRUE

What is the DRIVE Program Methodology?

Tableau Drive is a methodology for scaling out self-service analytics. Drive is based on best practices from successful enterprise deployments. The methodology relies on iterative, agile methods that are faster and more effective than traditional long-cycle deployment. A cornerstone of this approach is a new model of partnership between business and IT.

What is Tableau?

Tableau is a business intelligence software. It allows anyone to connect to the respective data. Visualizes and creates interactive, shareable dashboards.

What is the maximum no. of rows Tableau can utilize at one time?

Tableau is not restricted by the no. of rows in the table. Customers use Tableau to access petabytes of data because it only retrieves the rows and columns needed to answer your questions.

What is Tableau Data Server?

Tableau server acts a middle man between Tableau users and the data. Tableau Data Server allows you to upload and share data extracts, preserve database connections, as well as reuse calculations and field metadata. This means any changes you make to the data-set, calculated fields, parameters, aliases, or definitions, can be saved and shared with others, allowing for a secure, centrally managed and standardized dataset. Additionally, you can leverage your server's resources to run queries on extracts without having to first transfer them to your local machine.

What are the three Edit Interactions options of a visual tile in Power BI Desktop?

The 3 edit interaction options are Filter, Highlight, and None. Filter: It completely filter a visual/tile based on the filter selection of another visual/tile. Highlight: It highlight only the related elements on the visual/tile, gray out the non-related items. None: It ignore the filter selection from another tile/visual.

How is the FILTER function used?

The FILTER function returns a table with a filter condition applied for each of its source table rows. The FILTER function is rarely used in isolation, it's generally used as a parameter to other functions such as CALCULATE. FILTER is an iterator and thus can negatively impact performance over large source tables. Complex filtering logic can be applied such as referencing a measure in a filter expression. FILTER(MyTable,[SalesMetric] > 500)

How to remove 'All' options from a Tableau auto-filter?

The auto-filter provides a feature of removing 'All' options by simply clicking the down arrow in the auto-filter heading. You can scroll down to 'Customize' in the dropdown and then uncheck the 'Show "All" Value' attribute. It can be activated by checking the field again.

What are the data sources for Power Map?

The data can either be present in Excel or could be present externally. To prepare your data, make sure all of the data is in Excel table format, where each row represents a unique record. Your column headings or row headings should contain text instead of actual data, so that Power Map will interpret it correctly when it plots the geographic coordinates. Using meaningful labels also makes value and category fields available to you when you design your tour in the Power Map Tour Editor pane. To use a table structure which more accurately represents time and geography inside Power Map, include all of the data in the table rows and use descriptive text labels in the column headings, like this: Example of correct table format - Power BI Interview Questions -Edureka In case you wish to load your data from an external source: In Excel, click Data > the connection you want in the Get External Data group. Follow the steps in the wizard that starts. On the last step of the wizard, make sure Add this data to the Data Model is checked.

Mention what is the difference between published data sources and embedded data sources in Tableau?

The difference between published data source and embedded data source is that, Published data source: It contains connection information that is independent of any workbook and can be used by multiple workbooks. Embedded data source: It contains connection information and is associated with a workbook.

How would you create trailing X month metrics via DAX against a non-standard calendar?

The solution will involve: CALCULATE function to control (take over) filter context of measures. ALL to remove existing filters on the date dimension. FILTER to identify which rows of the date dimension to use. Alternatively, CONTAINS may be used: CALCULATE(FILTER(ALL('DATE'),.......))

What are the different types of refreshing data for our published reports?

There are four main types of refresh in Power BI. Package refresh, model or data refresh, tile refresh and visual container refresh. Package refresh This synchronizes your Power BI Desktop, or Excel, file between the Power BI service and OneDrive, or SharePoint Online. However, this does not pull data from the original data source. The dataset in Power BI will only be updated with what is in the file within OneDrive, or SharePoint Online. Model/data refresh It referrs to refreshing the dataset, within the Power BI service, with data from the original data source. This is done by either using scheduled refresh, or refresh now. This requires a gateway for on-premises data sources. Tile refresh Tile refresh updates the cache for tile visuals, on the dashboard, once data changes. This happens about every fifteen minutes. You can also force a tile refresh by selecting the ellipsis (...) in the upper right of a dashboard and selecting Refresh dashboard tiles. Visual container refresh Refreshing the visual container updates the cached report visuals, within a report, once the data changes. To know more about data refresh and understand how to implement data refresh, you can check the following link.

What is DAX?

To do basic calculation and data analysis on data in power pivot, we use Data Analysis Expression (DAX). It is formula language used to compute calculated column and calculated field.

Organizational content packs provide users, BI professionals, and system integrator the tools to build their own content packs to share purpose-built _____________, _______________, and _______________ within their organization.

dashboards, reports, and datasets

TRUE OR FALSE: DAX can modify or insert data.

FALSE: DAX can not modify or insert data.

What is story in Tableau?

A story is a sheet that contains a sequence of worksheets or dashboards that work together to convey information. You can create stories to show how facts are connected, provide context, demonstrate how decisions relate to outcomes, or simply make a compelling case. Each individual sheet in a story is called a story point.

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

According to your question you must have state, city, profit and sales fields in your dataset. Step 1: Double click on the state field Step 2: Drag the city and drop it into Marks card. Step 3: Drag the sales and drop it into size. Step 4: Drag profit and drop it into color. Step 5: Click on size legend and increase the size. Step 6: Right click on state field and select show quick filter. Step 7: Select any state now and check the view.

How to add Custom Color to Tableau?

Adding a Custom Color refers to a power tool in Tableau. Restart you Tableau desktop once you save .tps file. From the Measures pane, drag the one you want to add color to Color. From the color legend menu arrow, select Edit Colors. When a dialog box opens, select the palette drop-down list and customize as per requirement.

Extract: connections

An extract will make a static snapshot of the data to be used by Tableau's data engine. The snapshot of the data can be refreshed on a recurring schedule as a whole or incrementally append data. One way to set up these schedules is via the Tableau server. The benefit of Tableau extract over live connection is that extract can be used anywhere without any connection and you can build your own visualization without connecting to database.

How does SSRS integrate with Power BI?

Below are some of the way through which SSRS can be integrated with Power BI: Certain SSRS Report items such as charts can be pinned to Power BI dashboards. Clicking the tile in Power BI dashboards will bring the user to the SSRS report. A subscription is created to keep the dashboard tile refreshed. Power BI reports will soon be able to be published to SSRS portal

What are some ways that Excel experience can be leveraged with Power BI?

Below are some of the ways through which we can leverage Power BI: The Power BI Publisher for Excel: Can be used to pin Excel items (charts, ranges, pivot tables) to Power BI Service. Can be used to connect to datasets and reports stored in Power BI Service. Excel workbooks can be uploaded to Power BI and viewed in the browser like Excel Services. Excel reports in the Power BI service can be shared via Content Packs like other reports. Excel workbooks (model and tables) can be exported to service for PBI report creation. Excel workbook Power Pivot models can be imported to Power BI Desktop models.

What are the different Excel BI add-in?

Below are the most important BI add-in to Excel: Power Query: It helps in finding, editing and loading external data. Power Pivot: Its mainly used for data modeling and analysis. Power View: It is used to design visual and interactively reports. Power Map: It helps to display insights on 3D Map.

How to use group in calculated field?

By adding the same calculation to 'Group By' clause in SQL query or creating a Calculated Field in the Data Window and using that field whenever you want to group the fields. Using groups in a calculation. You cannot reference ad-hoc groups in a calculation. Blend data using groups created in the secondary data source: Only calculated groups can be used in data blending if the group was created in the secondary data source. Use a group in another workbook. You can easily replicate a group in another workbook by copy and pasting a calculation.

What is a calculated column in Power BI and why would you use them?

Calculated Columns are DAX expressions that are computed during the model's processing/refresh process for each row of the given column and can be used like any other column in the model. Calculated columns are not compressed and thus consume more memory and result in reduced query performance. They can also reduce processing/refresh performance if applied on large fact tables and can make a model more difficult to maintain/support given that the calculated column is not present in the source system.

What are some common Power Query/Editor Transforms?

Changing Data Types, Filtering Rows, Choosing/Removing Columns, Grouping, Splitting a column into multiple columns, Adding new Columns ,etc.

How to create a calculated field in Tableau?

Click the drop down to the right of Dimensions on the Data pane and select "Create > Calculated Field" to open the calculation editor. Name the new field and create a formula.

Live: connections

Connecting live to a data set leverages its computational processing and storage. New queries will go to the database and will be reflected as new or updated within the data.

Mention what are different Tableau files?

Different Tableau files include: Workbooks: Workbooks hold one or more worksheets and dashboards Bookmarks: It contains a single worksheet and its an easy way to quickly share your work Packaged Workbooks: It contains a workbook along with any supporting local file data and background images Data Extraction Files: Extract files are a local copy of a subset or entire data source Data Connection Files: It's a small XML file with various connection information

What is default Data Blending Join?

Data blending is the ability to bring data from multiple data sources into one Tableau view, without the need for any special coding. A default blend is equivalent to a left outer join. However, by switching which data source is primary, or by filtering nulls, it is possible to emulate left, right and inner joins.

Files: data source in Power BI

Data can be imported from Excel (.xlsx, xlxm), Power BI Desktop files (.pbix) and Comma Separated Value (.csv).

What are Extracts and Schedules in Tableau server?

Data extracts are the first copies or subdivisions of the actual data from original data sources. The workbooks using data extracts instead of those using live DB connections are faster since the extracted data is imported in Tableau Engine.After this extraction of data, users can publish the workbook, which also publishes the extracts in Tableau Server. However, the workbook and extracts won't refresh unless users apply a scheduled refresh on the extract. Scheduled Refreshes are the scheduling tasks set for data extract refresh so that they get refreshed automatically while publishing a workbook with data extract. This also removes the burden of republishing the workbook every time the concerned data gets updated.

What is a dual axis?

Dual Axis is an excellent phenomenon supported by Tableau that helps users view two scales of two measures in the same graph. Many websites like Indeed.com and other make use of dual axis to show the comparison between two measures and their growth rate in a septic set of years. Dual axes let you compare multiple measures at once, having two independent axes layered on top of one another. This is how it looks like:

What are the differences between a Power BI Dataset, a Report, and a Dashboard?

Dataset: The source used to create reports and visuals/tiles. A data model (local to PBIX or XLSX) or model in an Analysis Services Server Data could be inside of model (imported) or a Direct Query connection to a source. Report: An individual Power BI Desktop file (PBIX) containing one or more report pages. Built for deep, interactive analysis experience for a given dataset (filters, formatting). Each Report is connected to atleast one dataset Each page containing one or more visuals or tiles. Dashboard: a collection of visuals or tiles from different reports and, optionally, a pinned. Built to aggregate primary visuals and metrics from multiple datasets.

Microsoft has two parts for Self-Service BI

Excel BI Toolkit and Power BI

Limitations: Filter parameters can reference a metric.(TRUE OR FALSE)

False: Filter parameters cannot reference a metric.

TRUE OR FALSE The filter is not always visible. Sometimes you want a filter for the entire report, but you do not want any visual indication of the filter being applied.

False: The filter is always visible

What data sources can Power BI connect to?

Files: Content Packs: Connectors

What are the primary requirement for a table to be used in Power Map?

For a data to be consumed in power map there should be location data like: Latitude/Longitude pair Street, City, Country/Region, Zip Code/Postal Code, and State/Province, which can be geolocated by Bing The primary requirement for the table is that it contains unique rows. It must also contain location data, which can be in the form of a Latitude/Longitude pair, although this is not a requirement. You can use address fields instead, such as Street, City, Country/Region, Zip Code/Postal Code, and State/Province, which can be geolocated by Bing.

What is data management gateway and Power BI personal gateway?

Gateway acts a bridge between on-premises data sources and Azure cloud services. Personal Gateway: Import Only, Power BI Service Only, No central monitoring/managing. Can only be used by one person (personal); can't allow others to use this gateway. On-Premises Gateway: Import and Direct Query supported. Multiple users of the gateway for developing content. Central monitoring and control.

Name the components of a Dashboard.

Horizontal - Horizontal layout containers allow the designer to group worksheets and dashboard components left to right across your page and edit the height of all elements at once. Vertical - Vertical containers allow the user to group worksheets and dashboard components top to bottom down your page and edit the width of all elements at once. Text - All textual fields. Image Extract - A Tableau workbook is in XML format. In order to extracts images, Tableau applies some codes to extract an image which can be stored in XML. Web [URL ACTION] - A URL action is a hyperlink that points to a Web page, file, or other web-based resource outside of Tableau. You can use URL actions to link to more information about your data that may be hosted outside of your data source. To make the link relevant to your data, you can substitute field values of a selection into the URL as parameters.

Explain when would you use Joins vs. Blending in Tableau?

If data resides in a single source, it is always desirable to use Joins. When your data is not in one place blending is the most viable way to create a left join like the connection between your primary and secondary data sources.

Suppose my license expires today, will users be able to view dashboards or workbooks which I published in the server earlier?

If your server license expires today, your username on the server will have the role 'unlicensed' which means you cannot access but others can. The site admin can change the ownership to another person so that the extracts do not fail.

What are the different filters in Tableau and how are they different from each other?

In Tableau, filters are used to restrict the data from database. The different filters in Tableau are: Quick , Context and Normal/Traditional filter are: Normal Filter is used to restrict the data from database based on selected dimension or measure. A Traditional Filter can be created by simply dragging a field onto the 'Filters' shelf. Quick filter is used to view the filtering options and filter each worksheet on a dashboard while changing the values dynamically (within the range defined) during the run time. Context Filter is used to filter the data that is transferred to each individual worksheet. When a worksheet queries the data source, it creates a temporary, flat table that is uses to compute the chart. This temporary table includes all values that are not filtered out by either the Custom SQL or the Context Filter.

What do you understand by blended axis?

In Tableau, measures can share a single axis so that all the marks are shown in a single pane. Instead of adding rows and columns to the view, when you blend measures there is a single row or column and all of the values for each measure is shown along one continuous axis. We can blend multiple measures by simply dragging one measure or axis and dropping it onto an existing axis.

What is Power BI Designer?

It is a stand alone application where we can make Power BI reports and then upload it to Powerbi.com, it does not require Excel. Actually, it is a combination of Power Query, Power Pivot, and Power View.

What is Assume referential integrity?

In some cases, you can improve query performance by selecting the option to Assume Referential Integrity from the Data menu. When you use this option, Tableau will include the joined table in the query only if it is specifically referenced by fields in the view.

Excel BI Toolkit

It allows users to create an interactive report by importing data from different sources and model data according to report requirement.

Content Packs: data source in Power BI

It is a collection of related documents or files that are stored as a group. In Power BI, there are two types of content packs, firstly those from services providers like Google Analytics, Marketo or Salesforce and secondly those created and shared by other users in your organization.

What is Power Pivot Data Model?

It is a model that is made up of data types, tables, columns, and table relations. These data tables are typically constructed for holding data for a business entity.

Tableau Desktop:

It is a self service business analytics and data visualization that anyone can use. It translates pictures of data into optimized queries. With tableau desktop, you can directly connect to data from your data warehouse for live upto date data analysis. You can also perform queries without writing a single line of code. Import all your data into Tableau's data engine from multiple sources & integrate altogether by combining multiple views in a interactive dashboard.

What is the difference between joining and blending in Tableau?

Joining term is used when you are combining data from the same source, for example, worksheet in an Excel file or tables in Oracle database While blending requires two completely defined data sources in your report.

What are many-to-many relationships and how can they be addressed in Power BI ?

Many to Many relationships involve a bridge or junction table reflecting the combinations of two dimensions (e.g. doctors and patients). Either all possible combinations or those combinations that have occurred. Bi-Directional Crossfiltering relationships can be used in PBIX. CROSSFILTER function can be used in Power Pivot for Excel. DAX can be used per metric to check and optionally modify the filter context.

What are Measures and Dimensions?

Measures are the numeric metrics or measurable quantities of the data, which can be analyzed by dimension table. Measures are stored in a table that contain foreign keys referring uniquely to the associated dimension tables. The table supports data storage at atomic level and thus, allows more number of records to be inserted at one time. For instance, a Sales table can have product key, customer key, promotion key, items sold, referring to a specific event. Dimensions are the descriptive attribute values for multiple dimensions of each attribute, defining multiple characteristics. A dimension table ,having reference of a product key form the table, can consist of product name, product type, size, color, description, etc.

What are the parts of Microsoft self-service business intelligence solution?

Microsoft has two parts for Self-Service BI

Is Power BI available on-premises?

No, Power BI is not available as a private, internal cloud service. However, with Power BI and Power BI Desktop, you can securely connect to your own on-premises data sources. With the On-premises Data Gateway, you can connect live to your on-premises SQL Server Analysis Services, and other data sources. You can also scheduled refresh with a centralized gateway. If a gateway is not available, you can refresh data from on-premises data sources using the Power BI Gateway - Personal.

Can we have more than one active relationship between two tables in data model of power pivot?

No, we cannot have more than one active relationship between two tables. However, can have more than one relationship between two tables but there will be only one active relationship and many inactive relationship. The dotted lines are inactive and continuous line are active.

How to do Performance Testing in Tableau?

Performance testing is again an important part of implementing tableau. This can be done by loading Testing Tableau Server with TabJolt, which is a "Point and Run" load generator created to perform QA. While TabJolt is not supported by tableau directly, it has to be installed using other open source products.

What is Power BI Q&A?

Power BI Q&A is a natural language tool which helps in querying your data and get the results you need from it. You do this by typing into a dialog box on your Dashboard, which the engine instantaneously generates an answer similar to Power View. Q&A interprets your questions and shows you a restated query of what it is looking from your data. Q&A was developed by Server and Tools, Microsoft Research and the Bing teams to give you a complete feeling of truly exploring your data.

How is data security implemented in Power BI ?

Power BI can apply Row Level Security roles to models. A DAX expression is applied on a table filtering its rows at query time. Dynamic security involves the use of USERNAME functions in security role definitions. Typically a table is created in the model that relates users to specific dimensions and a role.

What is Power BI?

Power BI is a cloud-based data sharing environment. Once you have developed reports using Power Query, Power Pivot and Power View, you can share your insights with your colleagues. This is where Power BI enters the equation. Power BI, which technically is an aspect of SharePoint online, lets you load Excel workbooks into the cloud and share them with a chosen group of co-workers. Not only that, but your colleagues can interact with your reports to apply filters and slicers to highlight data. They are completed by Power BI, a simple way of sharing your analysis and insights from the Microsoft cloud.

What are the different types of filters in Power BI Reports?

Power BI provides variety of option to filter report, data and visualization. The following are the list of Filter types. Visual-level Filters: Page-level Filters: Report-level Filters:

What is Power Map?

Power Map is an Excel add-in that provides you with a powerful set of tools to help you visualize and gain insight into large sets of data that have a geo-coded component. It can help you produce 3D visualizations by plotting upto a million data points in the form of column, heat, and bubble maps on top of a Bing map. If the data is time stamped, it can also produce interactive views that display, how the data changes over space and time.

What is Power Pivot?

Power Pivot is an add-in for Microsoft Excel 2010 that enables you to import millions of rows of data from multiple data sources into a single Excel workbook. It lets you create relationships between heterogeneous data, create calculated columns and measures using formulas, build PivotTables and PivotCharts. You can then further analyze the data so that you can make timely business decisions without requiring IT assistance.

Why do we need Power Query when Power Pivot can import data from mostly used sources?

Power Query is a self-service ETL (Extract, Transform, Load) tool which runs as an Excel add-in. It allows users to pull data from various sources, manipulate said data into a form that suits their needs and load it into Excel. It is most optimum to use Power Query over Power Pivot as it lets you not only load the data but also manipulate it as per the users needs while loading.

What is Power View?

Power View is a data visualization technology that lets you create interactive charts, graphs, maps, and other visuals which bring your data to life. Power View is available in Excel, SharePoint, SQL Server, and Power BI. The following pages provide details about different visualizations available in Power View: Charts Line charts Pie charts Maps Tiles Cards Images Tables Power View Multiples Visualizations Bubble and scatter charts Key performance indicators (KPIs)

What is Power Query?

Power query is a ETL Tool used to shape, clean and transform data using intuitive interfaces without having to use coding. It helps the user to: Import Data from wide range of sources from files, databases, big data, social media data, etc. Join and append data from multiple data sources. Shape data as per requirement by removing and adding data.

What is query folding in Power Query?

Query folding is when steps defined in Power Query/Query Editor are translated into SQL and executed by the source database rather than the client machine. It's important for processing performance and scalability, given limited resources on the client machine.

What are query parameters and Power BI templates?

Query parameters can be used to provide users of a local Power BI Desktop report with a prompt, to specify the values they're interested in. The parameter selection can then be used by the query and calculations. PBIX files can be exported as Templates (PBIT files). Templates contain everything in the PBIX except the data itself. Parameters and templates can make it possible to share/email smaller template files and limit the amount of data loaded into the local PBIX files, improving processing time and experience .

What is self-service business intelligence?

SSBI is an approach to data analytics that enables business users to filter, segment, and, analyze their data, without the in-depth technical knowledge in statistical analysis, business intelligence (BI). SSBI has made it easier for end users to access their data and create various visuals to get better business insights. Anybody who has a basic understanding of the data can create reports to build intuitive and shareable dashboards.

What are the most common DAX Functions used?

SUM, MIN, MAX, AVG, COUNTROWS, DISTINCTCOUNT IF, AND, OR, SWITCH ISBLANK, ISFILTERED, ISCROSSFILTERED VALUES, ALL, FILTER, CALCULATE, UNION, INTERSECT, EXCEPT, NATURALINNERJOIN, NATURALLEFTEROUTERJOIN, SUMMARIZECOLUMNS, ISEMPTY, VAR (Variables) GEOMEAN, MEDIAN, DATEDIFF

What is the common table function for grouping data?

SUMMARIZE(): Main groupby function in SSAS. Recommended practice is to specify table and group by columns but not metrics. You can use ADDCOLUMNS function. SUMMARIZECOLUMNS: New group by function for SSAS and Power BI Desktop; more efficient. Specify group by columns, table, and expressions.

What are sets?

Sets are custom fields that define a subset of data based on some conditions. A set can be based on a computed condition, for example, a set may contain customers with sales over a certain threshold. Computed sets update as your data changes. Alternatively, a set can be based on specific data point in your view.

What does the Power BI features allow you to do:

Share presentations and queries with your colleagues. Update your Excel file from data sources that can be on-site or in the cloud. Display the output on multiple devices. This includes PCs, tablets, and HTML 5-enabled mobile devices that use the Power BI app. Query your data using natural language processing (or Q&A, as it is known).

What are the different types of joins in Tableau?

The joins in Tableau are same as SQL joins. Take a look at the diagram below to understand it.

What is xVelocity in-memory analytics engine used in Power Pivot?

The main engine behind power pivot is the xVelocity in-memory analytics engine. It can handle large amount of data because it stores data in columnar databases, and in memory analytics which results in faster processing of data as it loads all data to RAM memory.

What is disaggregation and aggregation of data?

The process of viewing numeric values or measures at higher and more summarized levels of the data is called aggregation. When you place a measure on a shelf, Tableau automatically aggregates the data, usually by summing it. You can easily determine the aggregation applied to a field because the function always appears in front of the field's name when it is placed on a shelf. For example, Sales becomes SUM(Sales). You can aggregate measures using Tableau only for relational data sources. Multidimensional data sources contain aggregated data only. In Tableau, multidimensional data sources are supported only in Windows. According to Tableau, Disaggregating your data allows you to view every row of the data source which can be useful when you are analyzing measures that you may want to use both independently and dependently in the view. For example, you may be analyzing the results from a product satisfaction survey with the Age of participants along one axis. You can aggregate the Age field to determine the average age of participants or disaggregate the data to determine what age participants were most satisfied with the product.

Why might you have a table in the model without any relationships to other tables?

There are mainly 2 reasons why we would have tables without relations in our model: A disconnected table might be used to present the user with parameter values to be exposed and selected in slicers (e.g. growth assumption.) DAX metrics could retrieve this selection and use it with other calculations/metrics. A disconnected table may also be used as a placeholder for metrics in the user interface. It may not contain any rows of data and its columns could be hidden but all metrics are visible.

How to create stories in Tableau?

There are many ways to create story in Tableau. Each story point can be based on a different view or dashboard, or the entire story can be based on the same visualization, just seen at different stages, with different marks filtered and annotations added. You can use stories to make a business case or to simply narrate a sequence of events. Click the New Story tab. In the lower-left corner of the screen, choose a size for your story. Choose from one of the predefined sizes, or set a custom size, in pixels. By default, your story gets its title from its sheet name. To edit it, double-click the title. You can also change your title's font, color, and alignment. Click Apply to view your changes. To start building your story, drag a sheet from the Story tab on the left and drop it into the center of the view Click Add a caption to summarize the story point. To highlight a key takeaway for your viewers, drag a text object over to the story worksheet and type your comment. To further highlight the main idea of this story point, you can change a filter or sort on a field in the view, then save your changes by clicking Update above the navigator box.

What are the data destinations for Power Queries?

There are two destinations for output we get from power query: Load to a table in a worksheet. Load to the Excel Data Model.

What is the difference between discrete and continuous in Tableau?

There are two types of data roles in Tableau - discrete and continuous dimension. Discrete data roles are values that are counted as distinct and separate and can only take individual values within a range. Examples: number of threads in a sheet, customer name or row ID or State. Discrete values are shown as blue pills on the shelves and blue icons in the data window. Continuous data roles are used to measure continuous data and can take on any value within a finite or infinite interval. Examples: unit price, time and profit or order quantity. Continuous variables behave in a similar way in that they can take on any value. Continuous values are shown as green pills.

What is special or unique about the CALCULATE and CALCULATETABLE functions?

These are the only functions that allow you modify filter context of measures or tables. Add to existing filter context of queries. Override filter context from queries. Remove existing filter context from queries.

Page-level Filters:

These filters work at the report-page level. Different pages in the same report can have different page-level filters.

Visual-level Filters:

These filters work on only an individual visualization, reducing the amount of data that the visualization can see. Moreover, visual-level filters can filter both data and calculations.

Report-level Filters:

These filters work on the entire report, filtering all pages and visualizations included in the report. We know that Power BI visual have interactions feature, which makes filtering a report a breeze. Visual interactions are useful, but they come with some limitations:

What are shelves?

They are Named areas to the left and top of the view. You build views by placing fields onto the shelves. Some shelves are available only when you select certain mark types.

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

This happens when a user is trying to publish a workbook that is connected to an internal server or a file stored on a local drive, such as a SQL server that is within a company's network. I hope that this Tableau Interview Questions were helpful to you. I will be coming up with more blogs on Tableau for you all very soon.

Tableau Public:

This is a free Tableau software which you can use to make visualizations with but you need to save your workbook or worksheets in the Tableau Server which can be viewed by anyone.

Tableau Online:

This is a hosted version of Tableau server which helps makes business intelligence faster and easier than before. You can publish Tableau dashboards with Tableau Desktop and share them with colleagues.

What is the difference between Traditional BI Tools and Tableau?

Traditional BI Tools 1. Architecture has hardware limitations. 2. Based on a complex set of technologies. 3. Do not support in-memory, multi-thread, multi-core computing. 4. Has a predefined view of data. Tableau 1. Do not have dependencies. 2. Based on Associative Search which makes it dynamic and fast 3. Supports in memory when used with advanced technologies. 4. Uses predictive analysis for various business operations.

tree map

also does the same except it is considered a very powerful visualization as it can be used for illustrating hierarchical data and part-to-whole relationships.

How to view underlying SQL Queries in Tableau?

Viewing underlying SQL Queries in Tableau provides two options: Create a Performance Recording to record performance information about the main events you interact with workbook. Users can view the performance metrics in a workbook created by Tableau. Help -> Settings and Performance -> Start Performance Recording Help -> Setting and Performance -> Stop Performance Recording. Reviewing the Tableau Desktop Logs located at C:\Users\\My Documents\My Tableau Repository. For live connection to data source, you can check log.txt and tabprotosrv.txt files. For an extract, check tdeserver.txt file.

What are some of the differences in report authoring capabilities between using a live or direct query connection such as to an Analysis Services model, relative to working with a data model local to the Power BI Desktop file?

With a data model local to the PBIX file (or Power Pivot workbook), the author has full control over the queries, the modeling/relationships, the metadata and the metrics. With a live connection to an Analysis Services database (cube) the user cannot create new metrics, import new data, change the formatting of the metrics, etc - the user can only use the visualization, analytics, and formatting available on the report canvas. With a direct query model in Power BI to SQL Server, for example, the author has access to the same features (and limitations) available to SSAS Direct Query mode. Only one data source (one database on one server) may be used, certain DAX functions are not optimized, and the user cannot use Query Editor functions that cannot be translated into SQL statements.

Can we refresh our Power BI reports once uploaded to cloud (Share point or Powebi.com)?

Yes we can refresh our reports through Data Management gateway(for sharepoint), and Power BI Personal gateway(for Powerbi.com)

Is Tableau software good for strategic acquisition?

Yes! For sure. It gives you data insight to the extent that other tools can't. Moreover, it also helps you to plan and point the anomalies and improvise your process for betterment of your company.

Can Tableau be installed on MacOS?

Yes, Tableau Desktop can be installed on both on Mac and Windows Operating System.

Can SQL and Power Query/Query Editor be used together?

Yes, a SQL statement can be defined as the source of a Power Query/M function for additional processing/logic. This would be a good practice to ensure that an efficient database query is passed to the source and avoid unnecessary processing and complexity by the client machine and M function.

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

Yes, one can create relational joins in tableau without creating a new table.

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

Yes, we can do it. But for better performance we should use Extract.

How to embed views onto Webpages?

You can embed interactive Tableau views and dashboards into web pages, blogs, wiki pages, web applications, and intranet portals. Embedded views update as the underlying data changes, or as their workbooks are updated on Tableau Server. Embedded views follow the same licensing and permission restrictions used on Tableau Server. That is, to see a Tableau view that's embedded in a web page, the person accessing the view must also have an account on Tableau Server. Alternatively, if your organization uses a core-based license on Tableau Server, a Guest account is available. This allows people in your organization to view and interact with Tableau views embedded in web pages without having to sign in to the server. Contact your server or site administrator to find out if the Guest user is enabled for the site you publish to. You can do the following to embed views and adjust their default appearance: Get the embed code provided with a view: The Share button at the top of each view includes embed code that you can copy and paste into your webpage. (The Share button doesn't appear in embedded views if you change the showShareOptions parameter to false in the code.) Customize the embed code: You can customize the embed code using parameters that control the toolbar, tabs, and more. For more information, see Parameters for Embed Code. Use the Tableau JavaScript API: Web developers can use Tableau JavaScript objects in web applications. To get access to the API, documentation, code examples, and the Tableau developer community, see the Tableau Developer Portal.

How many maximum tables can you join in Tableau?

You can join a maximum of 32 tables in Tableau.

What is the Power BI Publisher for Excel?

You can use Power BI publisher for Excel to pin ranges, pivot tables and charts to Power BI. The user can manage the tiles - refresh them, remove them, in Excel. Pinned items must be removed from the dashboard in the service (removing in Excel only deletes the connection). The Power BI Publisher for Excel can also be used to connect from Excel to datasets that are hosted in the Power BI Service. An Excel pivot table is generated with a connection (ODC file) to the data in Azure. The Publisher installs all necessary drivers on local machine to establish connectivity .

How to automate reports?

You need to publish report to tableau server, while publishing you will find one option to schedule reports.You just need to select the time when you want to refresh data.

What are content packs in Power BI?

for services are pre-built solutions for popular services as part of the Power BI experience. A subscriber to a supported service, can quickly connect to their account from Power BI to see their data through live dashboards and interactive reports that have been pre-built for them. Microsoft has released content packs for popular services such as Salesforce.com, Marketo, Adobe Analytics, Azure Mobile Engagement, CircuitID, comScore Digital Analytix, Quickbooks Online, SQL Sentry and tyGraph.

Datasets: The Building Blocks in Power BI

is a collection of data that Power BI uses to create its visualizations. Example: Excel sheets, Oracle or SQL server tables.

Reports: The Building Blocks in Power BI

is a collection of visualizations that appear together on one or more pages. Example: Sales by Country, State, City Report, Logistic Performance report, Profit by Products report etc.

What is Power BI Desktop?

is a free desktop application that can be installed right on your own computer. Power BI Desktop works cohesively with the Power BI service by providing advanced data exploration, shaping, modeling, and creating report with highly interactive visualizations. You can save your work to a file or publish your data and reports right to your Power BI site to share with others.

Tiles: The Building Blocks in Power BI

is a single visualization in a report or on a dashboard. Example: Pie Chart in Dashboard or Report.

Visualizations: The Building Blocks in Power BI

is a visual representation of data. Example: Pie Chart, Line Graph, Side by Side Bar Charts, Graphical Presentation of the source data on top of Geographical Map, Tree Map, etc.

Dashboards: The Building Blocks in Power BI

is single layer presentation of multiple visualizations, i.e we can integrate one or more visualizations into one page layer. Example: Sales dashboard can have pie charts, geographical maps and bar charts.

Connectors data source in Power BI

to databases and other datasets such as Azure SQL Database, and SQL Server Analysis Services, tabular data, etc.