DAX SUMMARIZECOLUMNS Function

DAX SUMMARIZECOLUMNS Function

The SUMMARIZECOLUMNS function in DAX is a powerful tool used in Power BI to group and summarize the data. It is often preferred over the older SUMMARIZE function because it’s faster, simpler to write, and works better when building reports. With SUMMARIZECOLUMNS, you can easily create DAX summary tables, apply filters, and calculate values like total sales or quantity. In this blog, you will explore how to use the SUMMARIZECOLUMNS function in Power BI to load data, create summaries, and improve your DAX reports.

Table of Contents:

Why Use SUMMARIZECOLUMNS in Power BI DAX Functions?

SUMMARIZECOLUMNS DAX is a function used in Power BI that improves query performance and code writing for you. Unlike SUMMARIZE, it identifies the correct data sources by removing unnecessary complexity. It also generates better queries, which ultimately help with large data sources. By using SUMMARIZECOLUMNS in DAX, you reduce the execution time of the query and make better reports.

When Should You Use SUMMARIZECOLUMNS in Power BI DAX Functions?

Use SUMMARIZECOLUMNS DAX when you need to create fast, efficient DAX summary tables in Power BI. It is ideal for building reports and dashboards where grouping and aggregation are required. Compared to older functions, DAX vs SUMMARIZECOLUMNS shows clear advantages in performance, syntax simplicity, and filter support.

SUMMARIZECOLUMNS Power BI is best used when:

  • You need to summarize data across related tables
  • You want better performance with large datasets
  • You need dynamic filtering in visuals
  • You want to simplify complex aggregation logic

As part of core Power BI DAX functions, SUMMARIZECOLUMNS is preferred for building optimized summary tables in report visuals.

Advantages of Using SUMMARIZECOLUMNS in Power BI

  • Enhanced Performance: This means better performance with less processing time and better query plans.
  • Simplified Syntax: There is better syntax since you do not need to reference the base table.
  • More Flexible Filtering: Multiple filters can be applied directly to the table.
  • Timely Reporting: Reports are cleaner and easier to combine with visuals and KPIs. 
  • Improved Context Management: Avoids unnecessary row context issues.

Sample Dataset

Tables that we use to perform calculations.

1. Sales Table

SalesID Product Color Quantity Unit Price Year
1 Laptop Silver 5 800 2021
2 Laptop Black 3 850 2021
3 Phone Silver 10 500 2020
4 Tablet White 7 300 2021
5 Phone Black 6 520 2022

2. Date Table

Year Month Day
2020 Jan 1
2021 Feb 10
2022 Mar 15

3. Product table

ProductID Product Color
101 Laptop Silver
102 Laptop Black
103 Phone Silver
104 Phone Black
105 Tablet White

Required Relationships:

To execute SUMMARIZECOLUMNS queries, make sure to establish the correct relationship between tables, as the wrong relationship may lead to incorrect results.

  • Date[Year] → Sales[Year](One-to-Many)
  • Sales[Product]→Product[Product](Many-to-One)

Steps to Use SUMMARIZECOLUMNS in Power BI

Let’s explore the steps to use SUMMARIZECOLUMNS in Power BI DAX Functions.

Step 1: Load your dataset

1. Sales Table

Sales Table for SUMMARIZECOLUMNS DAX

This is the Sales Table in Power BI.

2. Date Table

Date Table for  SUMMARIZECOLUMNS DAX

This is a Date Table in Power BI.

3. Product Table

Product Table for SUMMARIZECOLUMNS DAX

This is the Product Table in Power BI.

Step 2: Define your query

Create a DAX summary table of sales by year and product colour.
Go to “Model View,” click on “New Table,” and write the formula in the formula bar.

SalesSummary =
SUMMARIZECOLUMNS (
    'Date'[Year],
    'Product'[Color],
    "Total Sales", SUMX ( Sales, Sales[Quantity] * Sales[Unit Price] )
)
Define your query in SUMMARIZECOLUMNS Power BI

Explanation:

  • SalesSummary is used to create a new table and summarize data based on the logic
  • SUMMARIZECOLUMNS() is a function used to group and summarise data by specific columns.

Step 3: Output

Output for SUMMARIZECOLUMNS Power BI

Explanation: Here, the DAX function is used to summarize the three tables into one table.

Difference between SUMMARIZE and SUMMARIZECOLUMNS

Feature SUMMARIZECOLUMNS SUMMARIZE
Syntax Complexity Syntax is simple and easy to understand. SUMMARIZE by itself doesn’t allow expressions. To add calculations, you need to wrap them with ADDCOLUMNS
Performance Performance is better for large datasets. Performance is less efficient compared to SUMMARIZE.
Filtering Support It supports multiple filters in tables. It has limited filter options.
Ideal Use Case This function is used in report building and dashboards. SUMMARIZE can be used for basic grouping and is flexible, but may require additional functions for extended logic.
Debugging Harder to debug due to filter context and reliance on engine-generated query plans Easier to debug for simple logic, but can behave unpredictably when nested or poorly scoped.

Best Practices for DAX SUMMARIZECOLUMNS Function

  • Establish Relationships: Make sure that the correct relationships are set between tables to avoid incorrect output.
  • Minimise Filters: Apply only necessary filters to avoid unnecessary data processing. Use additional filters only when needed.
  • Use Aggregation: Perform calculations using SUMX instead of using nested queries, which make queries difficult to debug.
  • Test your formula: Test your DAX formula on sample data before applying it to actual data.
  • Name Your Table: When working with multiple tables in Power BI DAX functions, try to name all important tables with meaningful names to avoid any confusion.

Limitations of SUMMARIZECOLUMNS

  • No Row Context: SUMMARIZECOLUMNS operates in filter context and does not support row context by default, making row-wise operations like calculated columns behave differently.
  • Limited Debugging Support: Debugging SUMMARIZECOLUMNS is hard, as it is a complex expression.
  • Not for Complex Calculations: SUMMARIZECOLUMNS is used for aggregation but not for complex calculations.

Conclusion

SUMMARIZECOLUMNS is the best choice when you are building DAX queries, as it improves performance, is very easy to maintain, and is a powerful function that helps in aggregation tasks. Building reports in Power BI can be very efficient only if you are using SUMMARIZECOLUMNS, as it has a clear syntax and great compatibility with other DAX functions, and can be the best option in Power BI. In this blog, you have learned about SUMMARIZECOLUMNS and its usage.

To learn more about Power BI and its functions, check out this Power BI Course and also explore Power BI Interview Questions prepared by industry experts.

DAX SUMMARIZECOLUMNS Function – FAQs

Q1. What is SUMMARIZECOLUMNS used for?

SUMMARIZECOLUMNS is used to create a summary of a table with selected columns, which is helpful in aggregation.

Q2. How is SUMMARIZECOLUMNS different from SUMMARIZE?

SUMMARIZECOLUMNS has a simple syntax and handles filtering very well as compared to SUMMARIZE.

Q3. How to create summary tables in Power BI using DAX?

Use the SUMMARIZE() function in DAX to group data and create summary tables with custom aggregations.

Q4. Can I use SUMMARIZECOLUMNS in calculated tables?

Yes, you can use SUMMARIZECOLUMNS in the calculated table, as it helps in creating a summary of the table.

Q5. Does SUMMARIZECOLUMNS support filter context?

Yes, SUMMARIZECOLUMNS supports filter context as it can apply multiple filters using filter tables.

Q6. Can I use multiple tables in SUMMARIZECOLUMNS?

Yes, you can apply SUMMARIZECOLUMNS in multiple tables, but make sure that you define the correct relationship between them.

About the Author

Data Analyst & Machine Learning Associate

As a Data Analyst and machine learning associate, Nishtha combines her analytical skills and machine learning knowledge to interpret complicated datasets. She is also a passionate storyteller who transforms crucial findings into gripping tales that further influence data-driven decision-making in the business frontier.

Data Analytics for Business