Skip to main content
cancel
Showing results for 
Search instead for 
Did you mean: 

Grow your Fabric skills and prepare for the DP-600 certification exam by completing the latest Microsoft Fabric challenge.

Reply
Hoping
Helper II
Helper II

New columns to table added at source

Is it a recent change to Power BI service that new columns added to the table / view in the source database or warehouse will not flow through to the semantic model ?   As a concequence we have to update on power BI desktop and re-publish the model for it to include the source table changes ? 

 

I am pretty sure this wasn't the case 3 months back.

 

 

 

1 ACCEPTED SOLUTION
Martin_D
Super User
Super User

Hi @Hoping ,

I'd be surprised if columns were added automatically upon refresh. In the tabular model there is a static binding between semantic model columns and source columns. The columns you see is a static definition as part of the model, not coming dynamically from the source.

The reason is that data refreshes are technically partition refreshes, even if Power BI tables have only one partition except for incremental refresh tables. Since different partitions of the same table cannot have diffrent schemas, schema won't update upon refresh. There is no refresh type that includes a schema update. https://learn.microsoft.com/en-us/rest/api/power-bi/datasets/refresh-dataset#datasetrefreshtype

If you refresh data in Power BI Desktop this includes a schema update and an update of all partitions (including a full table, all partitions update of tables for which incremental refresh is configured). With Premium workspaces you could implement this yourself, writing a script that first does the schema update through XMLA and then triggers the data refresh. Adding a new column is always an explicit schema update of the tabular model. Update Tabular Model when the underlying Relational Database schema changes | Microsoft Learn

Kind regrds,

Martin

View solution in original post

1 REPLY 1
Martin_D
Super User
Super User

Hi @Hoping ,

I'd be surprised if columns were added automatically upon refresh. In the tabular model there is a static binding between semantic model columns and source columns. The columns you see is a static definition as part of the model, not coming dynamically from the source.

The reason is that data refreshes are technically partition refreshes, even if Power BI tables have only one partition except for incremental refresh tables. Since different partitions of the same table cannot have diffrent schemas, schema won't update upon refresh. There is no refresh type that includes a schema update. https://learn.microsoft.com/en-us/rest/api/power-bi/datasets/refresh-dataset#datasetrefreshtype

If you refresh data in Power BI Desktop this includes a schema update and an update of all partitions (including a full table, all partitions update of tables for which incremental refresh is configured). With Premium workspaces you could implement this yourself, writing a script that first does the schema update through XMLA and then triggers the data refresh. Adding a new column is always an explicit schema update of the tabular model. Update Tabular Model when the underlying Relational Database schema changes | Microsoft Learn

Kind regrds,

Martin

Helpful resources

Announcements
RTI Forums Carousel3

New forum boards available in Real-Time Intelligence.

Ask questions in Eventhouse and KQL, Eventstream, and Reflex.

MayPowerBICarousel1

Power BI Monthly Update - May 2024

Check out the May 2024 Power BI update to learn about new features.

Top Solution Authors