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Suryamaxillian's avatar
Suryamaxillian
Regular Visitor
10 months ago
Solved

Power BI refresh Error: Requested value 'None' was not found.

Requested value 'None' was not found. This error is showing while refreshing the data from MySQL in PowerBI. All the schema, table and column names are correct. It is happened after Navigati...
  • Mauro89's avatar
    Mauro89
    10 months ago

    Hi Suryamaxillian 

    That “Requested value 'None' was not found” error usually appears when Power Query encounters a metadata or type mismatch — often introduced after a schema or driver change in MySQL.

    Common causes might be:

    1. MySQL connector update or mismatch — sometimes the Power BI Desktop or Gateway driver version changes and the query references an outdated enum value.

    2. Changed data type or column metadata — if any column type changed (especially enum, set, or timestamp), the connector may fail to map it correctly.

    3. Navigation step caching — cached schema info from a previous session can cause this error after table renames or column changes.

    Try these fixes

    1. Rebuild the navigation step:

      • In Power Query, delete or temporarily disable the Navigation step.

      • Reconnect to your table again via Home → Recent Sources → MySQL and navigate to the same table.

      • Compare the auto-generated query to ensure the schema matches.

    2. Update your MySQL connector:

      • Download the latest official MySQL .NET Connector (8.3+ recommended).

      • Restart Power BI Desktop afterward.

    3. Clear Power Query cache:

      • Go to File → Options → Data Load → Clear cache.

      • Reopen your file and refresh.

    4. Check special column types:

    If your MySQL table includes enum or set fields, try casting them in SQL to varchar in a custom query:

    SELECT CAST(enum_column AS CHAR) AS enum_column, ... FROM your_table;

    Hope this helps you a bit.
     
    Best regards!
     
Mauro89's avatar
Mauro89
Icon for Super User rankSuper User
10 months ago

Hi Suryamaxillian 

That “Requested value 'None' was not found” error usually appears when Power Query encounters a metadata or type mismatch — often introduced after a schema or driver change in MySQL.

Common causes might be:

  1. MySQL connector update or mismatch — sometimes the Power BI Desktop or Gateway driver version changes and the query references an outdated enum value.

  2. Changed data type or column metadata — if any column type changed (especially enum, set, or timestamp), the connector may fail to map it correctly.

  3. Navigation step caching — cached schema info from a previous session can cause this error after table renames or column changes.

Try these fixes

  1. Rebuild the navigation step:

    • In Power Query, delete or temporarily disable the Navigation step.

    • Reconnect to your table again via Home → Recent Sources → MySQL and navigate to the same table.

    • Compare the auto-generated query to ensure the schema matches.

  2. Update your MySQL connector:

    • Download the latest official MySQL .NET Connector (8.3+ recommended).

    • Restart Power BI Desktop afterward.

  3. Clear Power Query cache:

    • Go to File → Options → Data Load → Clear cache.

    • Reopen your file and refresh.

  4. Check special column types:

If your MySQL table includes enum or set fields, try casting them in SQL to varchar in a custom query:

SELECT CAST(enum_column AS CHAR) AS enum_column, ... FROM your_table;

Hope this helps you a bit.
 
Best regards!