Forum Discussion

Hieudao's avatar
Hieudao
Frequent Visitor
9 months ago
Solved

Power BI Custom Visual – update() function resets dataView to 30k rows after drill up/down

Hi everyone, I'm developing a custom visual for Power BI, and I’m encountering an issue related to fetchMoreData() and the update() lifecycle when using drill up / expand down. --------------------...
Need Help
  • v-aatheeque's avatar
    v-aatheeque
    9 months ago

    Hi Hieudao 

    Thanks for sharing such detailed explanation.
    The configuration confirms that Power BI is applying a windowed data reduction of 30,000 rows. This behavior is by design in Power BI.

    When you drill up/down or navigate back to the page, Power BI reinitializes the visual and sends a fresh dataView starting from the first 30k rows. Even if you previously fetched all rows (105k), the visual does not persist that state across page navigation.

    The inconsistent columns/rows you observed (6 columns → 5 columns, 30k rows → 52k rows → back to 30k rows) happen because drill changes alter the schema (columns).

    To fix fetching data:

    In update(options), check options.type:
    If VisualUpdateType.All or VisualUpdateType.Data → clear previous cache and start fetching again.
    Always assume update() after drill or navigation is a fresh start.

     

    Hope this helps !!

    Thank You

v-aatheeque's avatar
v-aatheeque
Community Support
9 months ago

Hi Hieudao 

Thanks for sharing such detailed explanation.
The configuration confirms that Power BI is applying a windowed data reduction of 30,000 rows. This behavior is by design in Power BI.

When you drill up/down or navigate back to the page, Power BI reinitializes the visual and sends a fresh dataView starting from the first 30k rows. Even if you previously fetched all rows (105k), the visual does not persist that state across page navigation.

The inconsistent columns/rows you observed (6 columns → 5 columns, 30k rows → 52k rows → back to 30k rows) happen because drill changes alter the schema (columns).

To fix fetching data:

In update(options), check options.type:
If VisualUpdateType.All or VisualUpdateType.Data → clear previous cache and start fetching again.
Always assume update() after drill or navigation is a fresh start.

 

Hope this helps !!

Thank You

v-aatheeque's avatar
v-aatheeque
Community Support
8 months ago

Hi Hieudao 

Have you had a chance to look through the responses shared earlier? If anything is still unclear, we’ll be happy to provide additional support.

  • v-aatheeque's avatar
    v-aatheeque
    Community Support
    8 months ago

    Hi Hieudao 

    Following up to confirm if the earlier responses addressed your query. If not, please share your questions and we’ll assist further.