Explain what is Tableau Data Extract?

A table data extract is a compressed snapshot of data stored on disk and loaded into memory as required to render a Tableau. A TDE is a columnar store and reduce the input/output required to access and aggregate the values.

List the difference between parameters and filters in Tableau.

The difference actually lies in the application. Parameters allow users to insert their values, which can be integers, float, date, string that can be used in calculations. However, filters receive only values users choose to ‘filter by’ the list, which cannot be used to perform calculations.
Users can dynamically change measures and dimensions in parameter but filters do not approve of this feature.

Mention when to 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.

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.

Mention what are the characteristics to distinguish data source?

The data source are distinguished on the basis of following characteristics

• Icon/Name
• Connection Type
• Connects to 
• Live or Last extract

Define Data Modeling.

Data Modeling in Tableau allows rapid analysis of operational data that produce visual prints of data to help users identify consumer trends, sales targets and operational improvement. Data modeling processes minimize the use of manual changes in the data structure but promote automatic adaption to the changing environment.
It also allows real-time modeling by letting users share their analysis in the collaborative working environment.