Tableau Flashcards
Define LOD Expression
LOD expressions give you control on the level of granularity you want to compute independent of the values used in the visualization.
It allows you to run complex queries involving dimensions at the data source level instead of bringing all the data to the Tableau interface
What is the difference between dimensions and measures?
Dimensions
- contain qualitative values (such as names, dates, or geographical data)
- used to categorize or segment
Measures contain numeric, quantitative values and can be aggregated
What is Meant by ‘discrete’ and ‘continuous’ in Tableau?
Discrete - “individually separate and distinct” represented as blue and create headers or categories when brought into the view
Continuous - “forming an unbroken whole without interruption” represented as green forms a new axis
What is the Difference Between Joining and Blending?
data joining combining the data between two or more tables or sheets within the same data source
data blending is combining the data from two or more different sources where each data source contains its own set of dimensions and measures
What is the Difference Between a Live Connection and an Extract?
Tableau Data Extracts are snapshots of data optimized for aggregation and loaded into system memory to be quickly recalled for visualization
Live connections offer the convenience of real-time updates, with any changes in the data source reflected in Tableau
Difference Between Groups and Sets in Tableau
group is one dimensional, used to create a higher level category by using lower-level category members
sets can have conditions and can be grouped across multiple dimensions/measures.
What is a Parameter in Tableau?
A parameter is a dynamic value that lets the end user replace constant values in calculations, filters, and reference lines
What are the data types supported in Tableau?
Text (string) values. Date values. Date and time values. Numerical values. Boolean values (relational only) Geographical values (used with maps)
What are the different filter types in Tableau?
Extract Filters. Data Source Filters. Context Filters. Dimension Filters. Measure Filters. Table Filters.
Types of joins
Inner - resulting table on contains values that have matches in both tables
Left - all values in left table and corresponding matching values from right table
Full outer - all values from both tables
What is a Calculated Field?
A calculated field is a new field created form existing data in the data source that is used to create more robust visualizations and doesn’t affect the original dataset
What is the difference between Treemaps and Heat maps?
They are similar in that they both use color and size, but
Tree map is used to represent hierarchical data as parts of a whole where
Heat map compares values across categories
What is the difference between .twbx and .twb?
.twbx is a packaged workbook that contains all the information along with the data source.
.twb is just the xml document that contains instructions on how to interact with the data source but not the data itself
When would you apply a blended axis?
You can use two measures to share an axis when they have the same scale.
Example seeing sales and profit over time
What is the use of dual-axis?
Dual axis allows you to compare measures that have different scales. Because dual axis gives you 2 different marks cards, you can have different mark types, for example a line and bar chart.
