1-What is Data Visualization?
A much advanced, direct, precise and ordered way of
viewing large volumes of data is called data visualization. It is the visual representation of data in the form of graphs and charts, especially when you can’t define it textually. You can show trends, patterns and correlations through various data visualization software and tools; Tableau is one such data visualization software used by businesses and corporates.
2-Define Dimensions & Measure?
Dimensions are the descriptive attribute values for multiple dimensions of each attribute, defining multiple characteristics. A dimension table, having reference to a product key form the fact table can consist of product name, product type, size, colour, description, etc.
Measure are quantitative measurements.
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Dimension
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Measure
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City
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Population
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Bilaspur
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5,000
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Korba
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4,000
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The behaviour of the dimension in Tableau:
In tableau dimensions always contains discrete values. Discrete values mean each and every
value is unique and it is independent of the remaining values.
The behaviour of the measures in Tableau:
Measures always contain continuous values. Continuous values mean all the values will
follow a specific order and it cannot be changed. It means each and every value is depending on other values.
3-What is Tableau?
Tableau is a business intelligence software that allows anyone to connect to respective data, and then visualize and create interactive, shareable dashboards
4-Name the file extensions in Tableau.
There are several file types and extensions in Tableau :
Tableau Workbook (.twb).
Tableau Packaged Workbook (.twbx).
Tableau Datasource (.tds).
Tableau Packaged Datasource (.tdsx).
Tableau Data extract (.tde).
Tableau Bookmark (.tdm).
Tableau Map Source (.tms).
Tableau Preferences (.tps)
5- Explain the difference between .twb and .twbx.
.twb is the most common file extension used in Tableau, which presents an XML format file and comprises all the information present in each dashboard and sheet-like what fields are used in the views, styles and formatting applied to a sheet and dashboard. But this workbook does not contain any data. The Packaged workbook merges the information in a Tableau workbook with the local data available (which is not on the server).
.twbx serves as a zip file, which will include custom images if any. Packaged Workbook allows users to share their workbook information with other Tableau Desktop users and let them open it in Tableau Reader.
6. 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.
Live: 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.
Extract: 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.
7. What are the 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 a specific data point in your view.
8. 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.
9. What is a hierarchical field?
A hierarchical field in the tableau is used for drilling down data. It means viewing your data at a more granular level.
10-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
Image Extract: – A Tableau workbook is in XML format. 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 another 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.
10. 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 a database.
The different filters in Tableau are: Quick, Context and Normal/Traditional filter are:
Normal Filter is used to restricting 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 filtering the data that is transferred to each individual worksheet. When a worksheet queries the data source, it creates a temporary, flat table that is used to compute the chart. This temporary table includes all values that are not filtered out by either the Custom SQL or the Context Filter.
11. Define parameters in Tableau and their working.
Tableau parameters are dynamic variables/values that replace the constant values in data calculations and filters. For instance, you can create a calculated field value returning true when the score is greater than 80 and otherwise false. Using parameters, one can replace the constant value of 80 and control it dynamically in the formula.
12. 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, a worksheet in an Excel file or tables in Oracle database
While blending requires two completely defined data sources in your report.
13.Data types in Tableau:
1. Global- Geographic
2. Textual fields
3. Hash (Numeric)
4. Date
5. Timestamp
14-Working with multiple measures:
Three ways are available to work with multiple measures in tableau.
1. Individual Axis
2. Blended Axis
3. Dual Axis
Individual Axis:
In the individual axis, tableau will create a separate axis for each measure which is part of the
data view.
Blended Axis:
Blending means mixing. In the tableau, if we mix the multiple measures into a single axis then such
a kind of axis is known as the blended axis.
Dual Axis:
Dual-axis is the third way to work with the multiple measures
15-Combination Charts:
If we combine multiple charts in the single worksheet then it is called a combination chart.
Combination charts are possible with the individual axis & dual axis because combination charts
require multiple marks cards.
16-Types of Maps-
In tableau 2 types of maps are available.
1. Symbol map.
2. Filled map.
Symbol map:
If we indicate each and every geographic location with a symbol then it is called a symbol map
and it is the default in tableau.
Filled map:
If we indicate the geographic value with the filled a portion in the map then it is called a filled map.
The default geographic roles are available in the tableau are
1. Country
2. State
3. City
4. District
5. Area code
6. Zipcode
7. Street
17-Default properties of textual dimension in tableau:
The default properties of textual dimensions are
1. Comment
2. Aliases
3. Colour
4. Shape
5. Sort
The default properties of a Date dimension are
1. Comment
2. Colour
3. Shape
4. Date format
5. Sort
6. Fiscal year start
The default properties of a Measure are:
1. Comment
2. Colour
3. Number format
4. Aggregation
5. Totals
18-Parameters:
Parameters allow the users to pass their own values in the tableau. Different types of
parameters are available in tableaus like float, integer, string, Boolean, date and date-time.
Values can be passed to parameters in 3 ways.
1. All: Which indicates any value can be passed.
2. List: in the list, we have to take the values manually or from an existing field.
3. Range: If the parameter of the type is number or range then the number can be passed in
the form of range.
If we create any parameter then the tableau will create the parameter under the parameter tab
of the data window.
A parameter is a reusable component in tableau.
19-Types of Charts
In the tableau, 3 types of charts are available.
1 Uni-variety charts
2 Bi-variety charts.
3 Multi-variety charts
Uni-variety charts:
If the chart is supporting only a single measure for the analysis then such a kind of chart is known
as uni-variety chart
Bi-variety Charts:
If the chart is supporting two measures for the analysis then it is known as the bi-variety chart.
Multi variety chart:
If the chart is supporting more than 2 measures for the analysis then such a kind of chart is
known as the multi-variety chart.
20-Bar Charts:
A bar chart is a great way to compare the categorical data. It is the default chart in tableau if you
want to compare any category against the measure. In Tableau 3 different kinds of bar chart are
available.
1. Horizontal bar chart
2. Stacked bar chart
3. Side by side
21-Line Charts
Line charts are the best way to compare the growth over the period.
If we take any data field in the table against any measure, Tableau automatically creates a line
chart. If the analysis contains any date or time fields then such a kind of analysis is known as
time-series analysis.
In the tableau, 2 different kinds of line charts are available.
1. Discrete lines
2. Continuous lines.
22. What is the Tableau Data Server?
Tableau server acts as 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.
23. What is the Tableau Data Engine?
Tableau Data Engine is a really cool feature in Tableau. It's 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 The engine is not really in-memory technology. The data is stored in disk after it is imported and the RAM is hardly utilized.
24-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.
25-What is the difference between a treemap and heat map?
A heat map can be used for comparing categories with colour and size. With heat maps, you can compare two different measures together.
Treemap 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.
26-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.
27. 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.
28. How to automate reports?
You need to publish the 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.
29. 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.
30. What is the 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.
31. 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 similarly in that they can take on any value. Continuous values are shown as green pills.
32. Mention what is the difference between published data sources and embedded data sources in Tableau?
The difference between a published data source and an 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.
33-What is Filters in tableau-
Ans-Clik on Below link
All about the filter in tableau
