Untitled Deck

Question 1

What does DAX stand for?

Answer 1

Data Analysis Expressions.

Question 2

What are the three types of calculations you can add using DAX?

Answer 2

Calculated tables, calculated columns, and measures.

Question 3

Are row-level security (RLS) rules considered model calculations?

Answer 3

No, they are not considered model calculations.

Question 4

What language is used to define RLS rules?

Answer 4

DAX.

Question 5

What is a calculated table in Power BI?

Answer 5

A table created using a DAX formula within the model.

Question 6

Can calculated tables connect to external data sources?

Answer 6

No, they cannot.

Question 7

How is the data in calculated tables stored?

Answer 7

It is imported into the model.

Question 8

What is a drawback of using calculated tables?

Answer 8

They increase storage size and can prolong refresh time.

Question 9

What Power Query feature is needed to connect to external data?

Answer 9

You must use Power Query for external data connections.

Question 10

Name three use cases for calculated tables.

Answer 10

Date tables, role-playing dimensions, and what-if analysis.

Question 11

Why are date tables important?

Answer 11

They enable DAX time intelligence functions.

Question 12

Which DAX functions can you use to create a date table?

Answer 12

CALENDAR and CALENDARAUTO.

Question 13

What is a role-playing dimension?

Answer 13

A dimension table used multiple times with different relationships.

Question 14

Give an example of role-playing dimensions.

Answer 14

A Sales table with OrderDateKey and ShipDateKey both related to a Date table.

Question 15

How many active relationships can exist between two tables in Power BI?

Answer 15

Only one active relationship.

Question 16

What function activates an inactive relationship in DAX?

Answer 16

USERELATIONSHIP.

Question 17

What’s an alternative design to a role-playing dimension?

Answer 17

Create duplicate calculated tables for each date role (e.g., Ship Date table).

Question 18

What type of table is created when you use a What-if parameter?

Answer 18

A calculated table.

Question 19

Are What-if parameter tables connected to other tables?

Answer 19

No, they are disconnected tables.

Question 20

Why are What-if tables called ‘disconnected’?

Answer 20

They don’t propagate filters to other tables.

Question 21

What is a calculated column in Power BI?

Answer 21

A column added to a table using a DAX formula.

Question 22

How often are calculated columns evaluated in Import mode?

Answer 22

During model refresh.

Question 23

How are calculated columns evaluated in DirectQuery mode?

Answer 23

They are evaluated by the underlying source database at query time.

Question 24

What does each row in a calculated column return?

Answer 24

A single value.

Question 25

Do calculated columns increase storage size?

Answer 25

Yes, when used with Import mode.

Question 26

How are calculated columns indicated in the Fields pane?

Answer 26

With a special icon.

Question 27

Can you create a calculated column in any table?

Answer 27

Yes, in any table within the model.

Question 28

What is a measure in Power BI?

Answer 28

A DAX formula that summarizes data and returns a single value.

Question 29

When is a measure evaluated?

Answer 29

At query time.

Question 30

Do measures increase the size of your data model?

Answer 30

No, because results are not stored.

Question 31

How are measures indicated in the Fields pane?

Answer 31

With a calculator icon.

Question 32

Give three examples of measures in a Sales table.

Answer 32

Cost, Profit, Revenue.

Question 33

What’s another name for explicitly written DAX measures?

Answer 33

Explicit measures.

Question 34

What are implicit measures?

Answer 34

Aggregations like sum or count created automatically by visuals.

Question 35

How are implicit measures indicated in the Fields pane?

Answer 35

With a sigma symbol ( ∑ ).

Question 36

Can any column be used as an implicit measure?

Answer 36

Yes, when added to a visual.

Question 37

Is there a concept of a 'calculated measure' in Power BI?

Answer 37

No, there is no such term; only calculated tables/columns and measures.

Question 38

What distinguishes calculated columns from columns created in Power Query?

Answer 38

Calculated columns are created using DAX; Power Query columns are not.

Question 39

What distinguishes a calculated table from an imported table?

Answer 39

A calculated table is created using DAX, not from a direct data source.

Question 40

Which DAX function would you use to create a date series?

Answer 40

CALENDAR or CALENDARAUTO.

Question 41

What function do you use to activate an inactive relationship in DAX?

Answer 41

USERELATIONSHIP.

Question 42

What do calculated columns and measures have in common?

Answer 42

Both return a single value per evaluation.

Question 43

What's a major difference between a calculated column and a measure?

Answer 43

Calculated columns are evaluated at refresh; measures at query time.

Question 44

Which DAX calculation type stores results in the model?

Answer 44

Calculated columns and calculated tables.

Question 45

Which DAX calculation type does NOT store results in the model?

Answer 45

Measures.

Question 46

What icon indicates a calculated column?

Answer 46

A special column icon (unique to calculated columns).

Question 47

What icon indicates a measure?

Answer 47

A calculator icon.

Question 48

What icon indicates an implicit measure?

Answer 48

Sigma symbol ( ∑ ).

Question 49

What is a practical use of a What-if parameter?

Answer 49

Letting users select an exchange rate to see its effect on revenue.

Question 50

Why might you duplicate a Date table as a calculated table?

Answer 50

To handle role-playing dimensions with multiple active relationships.