Model Data - 2 Flashcards
What are role-playing dimension tables?
Role-playing dimension tables are tables that have multiple relationships with fact tables.
For example, a date (in the dimension table) is used to create a relationship with an order date, ship date, and due date (in the fact table).
What are the are two ways to edit a relationship?
go to the Home Ribbon and then select ‘Manage relationships’, then select edit.
The second way is to double click on the line connecting the two tables.
What storage modes can you define roles for?
Import & DirectQuery
When using Analysis Services data model, where is RLS configured at?
RLS is configured in the source
Where are you able to view user roles?
In Power BI service & Desktop
What does dynamic row-level security do?
Dynamic Row Level security allows you to display different data to users within the same role.
What must the data model contain to utilize dynamic row-level security?
Your data model must contain the usernames of people who should have access to the relevant rows of data.
What two functions does Power BI have that allow you to get the user name of the current user for Dynamic Row-Level security?
USERNAME
USERPRINCIPALNAME
What will the DAX function USERNAME return?
DOMAIN\User
What will the DAX function USERPRINCIPALNAME return?
UPN (like email) - when you have a column in your data that contains the email address you can filter using USERPRINCIPALNAME
What is Object-level security?
Object Level Security hides tables, columns, and measures but also secures them
What 3rd party application is used to implement object-level security?
Tabular Editor
What view of Power BI should you be in to implement the Q&A visual?
You must be in Report View to start using Q&A
Where can you add other words your organization uses to describe the data fields for Q&A?
In the “Field synonyms” option (under Modeling, Q&A setup)
What is an implicit measure?
Measures automatically created by Power BI such as average, sum, count, etc…
What is an explicit measure?
A measure you create using DAX.
What’s the difference between measures and calculated columns?
You can see the results of calculated columns immediately but have to add measures to visuals to see the results.
What is the purpose of a variable?
A variable stores the result of an expression, which is passed as an argument to other expressions
What does the USERRELATIONSHIP function with CALCULATE activate?
USERRELATIONSHIP with CALCULATE activates an inactive relationship
What does the CROSSFILTER function with CALCULATE change?
the CROSSFILTER function with CALCULATE changes the filter direction
What DAX functions can you use as CALCULATE modifiers to ignore all filters?
ALL
ALLEXCEPT
ALLSELECTED
What can the function ALL remove filters from?
- One or more columns from the same table
- An entire table
- The whole data model (when ALL is used with no parameters)
If you want to remove filters from a column that’s sorted by another column, what you should you do to prevent getting unexpected results?
You should remove filters from both columns to prevent unexpected results.
What are the parameters of the ALL function?
TableNameOrColumnName (The name of an existing table or column.) - Optional
ColumnName (A column in the same base table. The column can be specified in optional parameters only when a column is used in the first argument, too.) - Optional Repeatable
How does the ALL function work?
Returns all the rows in a table, or all the values in a column, ignoring any filters that might have been applied.
How does the ALLEXCEPT function work?
Returns all the rows in a table except for those rows that are affected by the specified column filters.