Common LOD use cases (customer first purchase, cohorts) in Tableau - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does LOD stand for in Tableau?

LOD stands for Level of Detail. It lets you control the granularity of your calculations independently from the view.

beginner

How can you find a customer's first purchase date using LOD expressions?

Use a FIXED LOD expression like { FIXED [Customer ID] : MIN([Order Date]) } to get the earliest purchase date per customer.

beginner

What is a cohort in business intelligence?

A cohort is a group of customers who share a common characteristic, often grouped by their first purchase date or signup period.

intermediate

Why use FIXED LOD expressions for cohort analysis?

FIXED LOD expressions let you calculate metrics like first purchase date per customer regardless of the current view filters or dimensions.

intermediate

Give an example of a cohort calculation using LOD in Tableau.

You can create a cohort by fixing the first purchase month: { FIXED [Customer ID] : DATETRUNC('month', MIN([Order Date])) } to group customers by their first purchase month.

What does the FIXED keyword do in a Tableau LOD expression?

A Filters data before aggregation

B Changes the data source connection

C Aggregates data only for visible marks

D Calculates the value at a specified dimension level regardless of the view

FIXED calculates the expression at the specified dimension level, ignoring the view's dimensions.

Which LOD expression finds the first purchase date per customer?

A { INCLUDE [Customer ID] : MIN([Order Date]) }

B { FIXED [Customer ID] : MIN([Order Date]) }

C { FIXED [Customer ID] : MAX([Order Date]) }

D { EXCLUDE [Customer ID] : MIN([Order Date]) }

MIN([Order Date]) fixed by Customer ID returns the earliest purchase date per customer.

What is a cohort analysis typically used for?

A Grouping customers by their first purchase or signup date

B Calculating total sales per product

C Filtering out inactive customers

D Changing data source connections

Cohort analysis groups customers by shared characteristics like first purchase date to analyze behavior over time.

Which LOD type ignores the view filters except context filters?

A FIXED

B EXCLUDE

C INCLUDE

D FILTER

FIXED LOD expressions ignore dimension filters in the view except context filters.

How can you group customers by their first purchase month in Tableau?

A Use DATETRUNC('month', [Order Date]) directly

B Use { INCLUDE [Customer ID] : MAX([Order Date]) }

C Use { FIXED [Customer ID] : DATETRUNC('month', MIN([Order Date])) }

D Use { EXCLUDE [Customer ID] : MIN([Order Date]) }

This LOD expression fixes the first purchase month per customer for cohort grouping.

Explain how you would use LOD expressions to find each customer's first purchase date in Tableau.

Think about fixing the calculation at the customer level and finding the earliest date.

Describe what a cohort is and how LOD expressions help analyze cohorts in Tableau.

Focus on grouping customers by first purchase and how LOD controls granularity.