RELATED for cross-table values in Power BI - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the DAX formula to get the related product name from the Products table.

Power BI

ProductName = RELATED([1][ProductName])

Drag options to blanks, or click blank then click option'

ACustomers

BSales

CProducts

DOrders

Attempts:

3 left

💡 Hint

Common Mistakes

Using the current table name instead of the related table.

Confusing RELATED with LOOKUPVALUE.

The RELATED function fetches a value from a related table. Here, Products is the related table containing the ProductName column.

2fill in blank

medium

Complete the DAX formula to get the related customer city from the Customers table.

Power BI

CustomerCity = RELATED([1][City])

Drag options to blanks, or click blank then click option'

ACustomers

BProducts

CSales

DOrders

Attempts:

3 left

💡 Hint

Common Mistakes

Selecting a table that does not contain the City column.

Using the current table name instead of the related table.

The RELATED function retrieves the City from the Customers table, which is related to the current table.

3fill in blank

hard

Fix the error in the DAX formula to correctly get the related category name.

Power BI

CategoryName = RELATED([1][CategoryName])

Drag options to blanks, or click blank then click option'

ACategory

BCategories

CProducts

DSales

Attempts:

3 left

💡 Hint

Common Mistakes

Using singular instead of plural table names.

Using unrelated table names.

The correct related table is Categories. Using 'Category' or other names causes errors because the table name must match exactly.

4fill in blank

hard

Fill both blanks to create a measure that sums sales amount using RELATED to get the product price.

Power BI

TotalSales = SUMX(Sales, Sales[Quantity] * RELATED([1][[2]]))

Drag options to blanks, or click blank then click option'

AProducts

BPrice

CCost

DSalesAmount

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong table or column names.

Confusing Cost with Price.

The measure multiplies Quantity by the related Price from the Products table to calculate total sales.

5fill in blank

hard

Fill all three blanks to create a calculated column that shows the customer country from the related Customers table and the order year.

Power BI

CustomerCountryYear = RELATED([1][[2]]) & " - " & YEAR([3][OrderDate])

Drag options to blanks, or click blank then click option'

ACustomers

BCountry

COrders

DSales

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong table for OrderDate.

Mixing up column names.

This formula gets the Country from the related Customers table and combines it with the year extracted from the OrderDate in the Orders table.

Practice

1. What does the RELATED function do in Power BI?

easy

A. It creates a new relationship between two tables.

B. It fetches a value from a related table based on existing relationships.

C. It deletes rows from a related table.

D. It aggregates data within the same table.

Solution

1. Step 1: Understand the purpose of RELATED

   The RELATED function is designed to retrieve a value from another table that is connected through a relationship in the data model.

2. Step 2: Differentiate from other functions

   RELATED does not create relationships or delete data; it only fetches values from an existing related table.

3. Final Answer:

   It fetches a value from a related table based on existing relationships. -> Option B

4. Quick Check:

   RELATED fetches related values = A [OK]

Hint: RELATED pulls data from linked tables only [OK]

Common Mistakes:

• Thinking RELATED creates relationships
• Assuming RELATED works without a relationship
• Confusing RELATED with aggregation functions

2. Which of the following is the correct syntax to use RELATED in a calculated column to get the 'CategoryName' from a related 'Product Categories' table?

easy

A. RELATED('Product Categories'[CategoryName])

B. RELATED(Product Categories[CategoryName])

C. RELATED Product Categories[CategoryName]

D. RELATED[Product Categories.CategoryName]

Solution

1. Step 1: Recall correct RELATED syntax

   The RELATED function requires the table name in single quotes if it contains spaces or special characters, followed by the column name in square brackets.

2. Step 2: Check each option

   RELATED('Product Categories'[CategoryName]) uses the correct syntax. Without quotes around the table name with space it fails, missing parentheses fails, and bracket notation is invalid.

3. Final Answer:

   RELATED('Product Categories'[CategoryName]) -> Option A

4. Quick Check:

   RELATED syntax with quotes = B [OK]

Hint: Use single quotes around table names with spaces [OK]

Common Mistakes:

• Omitting quotes around table names
• Using dot notation inside RELATED
• Missing parentheses after RELATED

3. Given two tables: Orders with columns OrderID, ProductID, and Quantity, and Products with columns ProductID and Price. There is a relationship between Orders[ProductID] and Products[ProductID]. What will the following calculated column in Orders return?

OrderValue = Orders[Quantity] * RELATED(Products[Price])

medium

A. The total price for each order line by multiplying quantity with product price.

B. The sum of all product prices in the Products table.

C. The quantity multiplied by the total number of products.

D. An error because RELATED cannot be used in calculated columns.

Solution

1. Step 1: Understand the relationship and calculation

   RELATED fetches the price of the product for each order line by matching ProductID. Multiplying by Quantity gives the total value for that order line.

2. Step 2: Trace the calculation

   The formula computes the total price for each order line row-by-row by multiplying Quantity with the RELATED product Price. It does not aggregate or error out.

3. Final Answer:

   The total price for each order line by multiplying quantity with product price. -> Option A

4. Quick Check:

   Quantity * RELATED(Price) = line total = C [OK]

Hint: RELATED pulls matching row value for each row [OK]

Common Mistakes:

• Thinking RELATED aggregates values
• Assuming RELATED cannot be used in calculated columns
• Confusing multiplication with aggregation

4. You wrote this calculated column in the Sales table:

ProductCategory = RELATED(Product[Category])

But you get an error saying "The column 'Category' either doesn't exist or is not related." What is the most likely cause?

medium

A. The Sales table has duplicate rows causing RELATED to fail.

B. The RELATED function cannot be used in calculated columns.

C. There is no relationship between Sales and Product tables on the relevant keys.

D. The column name 'Category' is misspelled in the Product table.

Solution

1. Step 1: Analyze the error message

   The error indicates that RELATED cannot find a related row, usually because the tables are not connected by a relationship.

2. Step 2: Check other possibilities

   RELATED can be used in calculated columns. Misspelling would cause a different error, and duplicates don't cause this error.

3. Final Answer:

   There is no relationship between Sales and Product tables on the relevant keys. -> Option C

4. Quick Check:

   RELATED needs relationships = D [OK]

Hint: Check relationships if RELATED gives column not found error [OK]

Common Mistakes:

• Assuming RELATED works without relationships
• Ignoring spelling errors in column names
• Blaming data duplicates for RELATED errors

5. You have three tables: Sales (with ProductID and Quantity), Products (with ProductID, CategoryID, and CategoryName), and Categories (with CategoryID and CategoryName).

You want to create a calculated column in Sales that shows the CategoryName for each sale. Which DAX formula correctly uses RELATED to get this value?

hard

A. RELATED(Categories[CategoryName])

B. RELATED(RELATED(Categories[CategoryName]))

C. RELATED(Products[CategoryID]) & RELATED(Categories[CategoryName])

D. RELATED(Products[CategoryName])

Solution

1. Step 1: Understand the relationships

   Sales is related to Products by ProductID, and Products is related to Categories by CategoryID. Products contains CategoryName (likely via its own RELATED to Categories).

2. Step 2: Use RELATED with the correct direct relationship

   RELATED(Products[CategoryName]) fetches from the directly related Products table.

3. Step 3: Rule out others

   A targets an indirectly related table, C uses invalid concatenation on unrelated data, D has invalid syntax.

4. Final Answer:

   RELATED(Products[CategoryName]) -> Option D

5. Quick Check:

   RELATED fetches from directly related table = B [OK]

Hint: RELATED only fetches from directly related tables [OK]

Common Mistakes:

• Trying to chain RELATED calls
• Using RELATED on unrelated tables
• Assuming RELATED can fetch through multiple tables automatically