Best Practices for Adding Columns to a Snowflake View Without Breaking Power BI

[sirbaklava]

Hey everyone,

I have a Snowflake view that’s connected to Power BI Service through DataFlow Gen1, with a daily refresh schedule. Most of my reports are pulling from this DataFlow without any issues.

Now, I need to add a new column to the view to meet a report requirement. The problem is that if I update the view in Snowflake and add this column, the next Power BI refresh is going to fail—even though the new column isn't used in any measures or existing report logic.

Has anyone found a way to modify queries (e.g., adding columns) without causing refresh failures? Would appreciate any best practices or workarounds you guys use.

Thanks!

[Anonymous]

Thanks for the reply from nilendraFabric , please allow me to provide another insight:

Hi, @sirbaklava 
Thanks for reaching out to the Microsoft fabric community forum.

Based on what I understand, a potentially effective solution is to reconstruct the views in Snowflake. The issue you're encountering might be due to creating views using SELECT * from tables and then making changes to the columns in those tables. In such cases, querying the view can result in column-related errors. Below is a screenshot from the relevant documentation:

Additionally, as nilendraFabric mentioned, the CREATE OR REPLACE command is also discussed in the documentation:

For more details, please refer to the documentation:

https://docs.snowflake.cn/zh/sql-reference/sql/create-view

I hope our response is helpful to you. Looking forward to your reply.

Best Regards,

Leroy Lu

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

[nilendraFabric · Accepted solution]

Hello @sirbaklava 

as far as i know adding a new column to your data source (e.g., a Snowflake view) will not cause existing Power BI reports to fail, as long as the new column does not interfere with the existing schema or logic. Here’s why:

1. Schema Mismatch Handling: Power BI retains the schema of the data source at the time of its initial connection. When you add a new column, Power BI will simply ignore it during refreshes because it is not referenced in the dataset or reports. This means existing queries, measures, and visuals will continue to work without errors.

2. Impact on Existing Logic: Since the new column is not part of any existing queries, measures, or visuals in Power BI, it does not affect the current functionality of your reports. The refresh process will only query the columns that were part of the schema when the dataset was last configured.

Some best practices:

Use `CREATE OR REPLACE` for Snowflake Views

If you want new columns to be part of query

In Power BI’s Query Editor, set the query to dynamically include all columns by using `Columns=null` in the Advanced Editor. This ensures that any new columns added to the source are automatically included during refresh

if this is helpful please accept the answer and give kudos