Data Visualization and Analytics Flashcards

What is the main advantage of a Tableau extract (.hyper) over a live connection?

Answer: Faster performance and offline access via in-memory data

Extracts load data into Tableau's Hyper engine for fast, compressed, offline querying.

Which type of join combines rows only where matching keys exist in both tables?

Answer: Inner join

An inner join returns only records with matches in both tables.

What does data blending in Tableau allow you to do?

Answer: Combine data from different sources on a common field

Blending links separate data sources on a shared dimension at the aggregate level.

In Tableau Prep, what is the purpose of a 'clean' step?

Answer: Transform, filter, and fix data such as renaming or splitting fields

Clean steps apply transformations like splits, renames, filters, and grouping to prepare data.

Which operation reshapes columns into rows in Tableau?

Answer: Pivot

Pivoting converts wide column data into a tall key-value row format.

What does a UNION do to data in Tableau?

Answer: Stacks rows from tables with the same structure

A union appends rows from tables that share the same fields, increasing row count.

Why might you choose a live connection instead of an extract?

Answer: To always reflect up-to-the-moment source data

Live connections query the source directly, showing the latest data without refresh schedules.