Understanding Data Refresh

[jabrillo]

In my Power BI dashboard I have three tables with the same columns. I created a four table that combines the three tables. When I do selective data refresh and select the three tables only, will the combined table be updated automatically, or do I still do a data refresh on the combined table? I read somewhere that the loading of the three tables should be disabled (uncheck Enable Load). I'm a bit confused. Thank you for your help. 

[123abc]

n Power BI, when you have multiple tables in your data model and you create a new table that combines or references the data from these existing tables, it's important to understand how data refresh works in this context.

Here's what happens when you perform a selective data refresh:

1. Selective Data Refresh: When you initiate a selective data refresh and select the three individual tables (let's call them Table A, Table B, and Table C) to refresh, only those specific tables will be updated. This means that the data in Table A, Table B, and Table C will be refreshed with the latest data from their respective sources.

2. Combined Table: The combined table you created, which references or merges data from Table A, Table B, and Table C, will not be automatically updated during this selective refresh. The combined table doesn't refresh automatically because it doesn't have a direct connection to a data source; it relies on the data in the three individual tables.

3. Enabling Load: The recommendation to "disable load" (uncheck "Enable Load") for the three individual tables you are merging is a way to reduce the amount of data loaded into the data model. When you disable load for a table, Power BI will still load the table metadata and the query definition, but it won't load the actual data into the model. Instead, it will fetch the data from the source when needed.

Here's how you can manage the combined table:

• Refresh the Combined Table: If you want the combined table to be updated with the latest data from the three individual tables, you'll need to perform a separate data refresh specifically for the combined table. To do this, you can create a refresh operation for the combined table in Power Query or schedule regular refreshes for it.

• Data Dependencies: Keep in mind that the combined table has dependencies on Table A, Table B, and Table C. So, before refreshing the combined table, ensure that the underlying tables (Table A, Table B, and Table C) have been refreshed successfully and contain up-to-date data.

In summary, selective data refresh will update the individual tables you select, but the combined table will not be updated automatically. You will need to manage the refresh of the combined table separately, and disabling load for the individual tables is a technique to optimize data loading but doesn't impact the need to refresh the combined table.

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

[123abc · Accepted solution]

In Power BI, when you have multiple tables with the same columns and you create a fourth table that combines or merges these three tables, you need to understand how data refresh works to ensure your data stays up to date.

When you perform a selective data refresh and only select the three original tables for refresh, the combined table will not be updated automatically. The combined table is not linked directly to the refresh of the original tables. Therefore, if you want the data in the combined table to be updated, you should either:

1. Enable Load for the Combined Table:
- You can enable loading for the combined table by checking the "Enable Load" option in the Power Query Editor when creating or editing the combined table.
- This will ensure that the combined table gets refreshed along with the original tables when you perform a data refresh.

2. Perform a Separate Data Refresh for the Combined Table:
- If you prefer to keep "Enable Load" unchecked for the original tables, you can create a separate query to combine the data from the three tables.
- After creating this separate query for the combined table, you should also enable loading (check "Enable Load") for this query in the Power Query Editor.
- When you perform a data refresh, the combined table will then be updated as well.

The choice between these two options depends on your specific requirements and how you want to manage the data in your Power BI model. Enabling load for the combined table simplifies the refresh process, but it may also result in larger data storage, so consider your storage and performance constraints when making this decision.

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

[Ritaf1983]

Hi @jabrillo 
If you are talking about visual tables it does not matter how many of them you have, the data refreshes from the source. You don't refresh visuals you refresh the data in the "back".

If the question is about tables that you combined on PQ and all of them are loaded to the model, and not just combined, all of them should be refreshed.

I prepared some example and recorded my screens to show how it works 

Link to the media file 

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