41. What are the products offered by Tableau? Explain a few things about them.
Tableau has 4 main products.
- Tableau Prep: Tableau Prep is responsible for preparing data for analysis. This tool provides 3 coordinated views which provide us with a complete picture of data.
- Tableau Desktop: Tableau Desktop is the place where the analysis happens. It has powerful drag and drop analytics which is very easy to use. Through the desktop, you get your data insights quickly.
- Tableau Online: Tableau Online is a secure and scalable self-service analytics cloud tool. You can use it anywhere, anytime and it has eliminated the complexities of IT.
- Tableau Server: From small to large enterprises, Tableau server is used for fulfilling their BI requirements. This is an on-premise solution. This tool can take data from anywhere and shared it across the organization through the desktop or mobile browsers.
42. Differentiate parameters and filters in Tableau
Filters are the simpler and more straightforward feature in Tableau. It applies to dimensions or measures directly. For example, to only show Gujarat or Karnataka in a State dimension, we can apply the filter on that. In Tableau, there are multiple UI options available for filters like radio buttons, drop-down lists, checkboxes, sliders, and more. Filters on sheets are also available in Tableau. Parameters are like variables. They are complex and more powerful. Like a variable, a
parameter can be used in calculations. So, that means, it only allows a single value. Parameters have the same UI options except for checkboxes because checkboxes don’t have a single value. For example, we can create a parameter for interest rate and period, and then we can use these parameters to calculate interest and principal payments.
43. Explain how many types of filters are available in Tableau?
Filters are used to provide the correct information to viewers after removing unnecessary data. There are various types of filters available in Tableau.
- Extract Filters – Extract filters are used to apply filters on extracted data from the data source. For this filter, data is extracted from the data source and placed into the Tableau data repository.
- Datasource Filters – Datasource filters are the same as extract filters. They also work on the extracted dataset. But, the only difference is it works with both live and extract connections.
- Context Filters – Context Filters are applied on the data rows before any other filters. They are limited to views, but they can be applied on selected sheets. They define Aggregation and Disaggregation of data in Tableau
- Dimension Filters – Dimension filters are used to apply filters on dimensions in worksheets. Dimension filters are applied through the top or bottom conditions, formula, and wildcard match.
- Measure Filters – Measure filters are applied to the values present in the measures.
44. Differentiate between Tiled and Floating in Dashboards?
In a tiled layout, items don’t overlap. The layout will be adjusted according to the dashboard size. In the floating layout, items can be placed on some other layers. Floating items can have fixed positions and sizes.
45. Categorize dimensions in Tableau?
Dimensions are divided into 9 various categories
Slowly ever-changing dimension: The value of the dimension changes over an amount of time for slowly ever-changing dimensions.
Chop-chop ever-changing Dimension: Value in the dimension is rapidly changing for chop-chop ever-changing dimensions.
Unchanged Dimension: Values are constant for unchanged dimensions.
Shrunken Dimension: A set of 1 dimension is termed as Shrunken Dimension.
Junk Dimension: Junk values or unrelated dimensions are termed as Junk Dimension.
Conformed Dimension: If any dimension is provided by various business areas, then such a dimension is termed a Conformed Dimension.
Degenerated Dimension: Degenerated dimensions have primary keys only without any matter of info.
Role enjoying Dimension: If one dimension is employed in multiple roles, then they are termed as Role enjoying Dimensions.
Inferred Dimension: Empty dimensions are called inferred dimensions. They are usually used in ETL.
46. What is VIZQL in Tableau?
VIZQL is a Visual Inquiry Language. It is a combination of VIZ and SQL. It is similar to SQL language. But instead of SQL commands, the VIZQL language converts data queries into visual images.
47. Explain the disaggregation and aggregation of data in Tableau?
Aggregation → The process of summarizing the data and viewing a single numeric value is called aggregation. Example – sum/avg of salary for each employee
Disaggregation →The process of viewing each transaction for analyzing all the measures both dependently and independently. Example – individual salary transactions for each employee.
48. State the components of the Dashboard?
The dashboard consists of 5 components.
- Web: it consists of a web page embedded in the dashboard.
- Horizontal component: it is a horizontal layout container in which we can add objects.
- Vertical component: it is a vertical layout container in which we can add objects.
- Image Extract: it allows you to upload an image to the dashboard from a computer.
- Text: it is a small Wordpad where we can format and edit the text.
49. Differentiate discrete and continuous data roles in Tableau
Discrete data roles consist of values that are separate and distinct. Discrete data roles can take individual values within a range. For Example – cancer patients in the hospital, no. of threads in a sheet, state. Discrete values are displayed as blue icons in the data window and blue pills on shelves. Discrete fields can be sorted.
Continuous data roles consist of any value within the finite or infinite intervals. For Example – age, unit price, order quantity. Continuous values are displayed as green icons in the data window and green pills on shelves. Continuous fields cannot be sorted.
50. What is the difference between Traditional BI Tools and Tableau?
Traditional BI Tableau BI Architecture has hardware limitations. Tableau does not have dependencies. It does not support in-memory, multi-thread, and multi-core computing. It supports memory when using advanced technologies. It has a predefined view of data. It uses predictive analysis for various business operations. We should need a good knowledge of BI and skills. It is easy to work and understand without the knowledge of BI and the skills data security provides. Data security is not provided for the public, whereas in the professional version.
51. Define performance testing in terms of Tableau
We can check the performance of Tableau in the following 2 ways.
- We can create performance recordings to keep track of performance details of main events while interacting with workbooks. Then, these performance metrics can be viewed by the user and analyzed. Navigation to start/stop performance recording is Help→Settings and
Performance>→ Start Performance Recording Help→ Setting and Performance → Stop Performance Recording
- Review the logs created by Tableau Desktop. The location for log files is C: Users My DocumentsMy Tableau Repository.
- For live connection, check the log files log.txt and tabprotosrv.txt.
- For Extract connection, check the log file tdeserver.txt
52. What is the difference between .twb and .twbx extensions?
.twb: .twb means Tableau workbook. .twb is an XML sheet that stores the data about your documents, stories, and dashboards. This file is the reference to the source file such as Excel or tde. This file will be linked to your source file when you save the TWB file. If you want to share your workbook you need to send both the workbook and data source file.
.twbx: It is a compressed file, where you have all files. It includes data source files, twb, and other files to produce the workbook. TWBX is obsolete for sharing because it will share the copy of the file instead of an original source file. .twbx is used for reports and we can view them using the Tableau viewer.
53. Why Tableau?
- Tableau is very simple and user-friendly.
- Tableau helps in analyzing the data and using this one can change the raw data into an understandable format.
- Users can blend the data with the other data to create their own views on the data and to share it with the customers, and colleagues.
- Users can manage a large amount of data.
- It can easily integrate with multiple data sources.
- Tableau can create complex graphs which simply look like pivot table graphs in Excel.
- It gives quick calculations on datasets.
- Users can create the visuals easily and switch between the types, to find the model to represent the user messages.
54. How to create a calculated field in Tableau?
Step 1: Select Analysis -> drop down will open -> Select Create calculated field
Step 2: The Calculation Editor Box will open, and give the name to the calculated field.
Step 3: Enter a formula in the calculation editor.
Example: Sum(Profits)/Sum(Sales). (Calculation Editor validates the formula)
Step 4: Click, OK.
Now, the new calculated field is added to the data pane.
55. Are there any limitations of parameters in Tableau? If yes, give details.
Tableau dashboard allows the representation of parameters in four ways only. They don’t allow any multiple values like a filter can do. They only allow a single value.
56. State some reasons for the low performance of Tableau? Explain in detail.
The following are the reasons for low performance
- Filters – filters need to create an extra query and if it is used in large numbers and inefficiently then they can reduce the performance. So, it is advised to use filters whenever it is mandatory
- Live connection – Tableau extract works much better in comparison with a live connection.
- Data sources – a wrong query to a wrong data source can reduce performance. Also, the data source’s performance can also affect Tableau’s performance.
57. State some ways to improve the performance of Tableau.
Following are a few ways to improve the performance
- Use an Extract to make workbooks run faster
- Reduce the scope of data to decrease the volume of data
- Reduce the number of marks on the view to avoid information overload
- Try to use integers or Booleans in calculations as they are much faster than strings
- Hide unused fields
- Use Context filters
- Reduce filter usage and use some alternative way to achieve the same result
- Use indexing in tables and use the same fields for filtering
- Remove unnecessary calculations and sheets.
58. Tell me different ways to use parameters in Tableau
- Filters
- Calculated fields
- Actions
- Measure-swaps
- Changing views
- Auto-updates.
59. Can we see SQL generated by Tableau Desktop?
Tableau Desktop Log files are placed in C: UsersMy DocumentsMy Tableau Repository. In case of live connection to any data source, check the log file “log.txt” and “tabprotosrv.txt” files. In case of extract connection to any data source, check the “tdeserver.txt” file which has detailed information about queries.
60. If the owner of the published workbook license expires, then can other users see those workbooks?
If the owner of a published workbook license expires then his/her role will change to “Unlicensed”. He/She cannot access those workbooks, but others can. Only site admin can change the ownership of those workbooks.
