What causes DM_ErrorCode_BackEnd_QueryExecutionFailed_DirectQuery?

The DirectQuery-generated SQL was rejected by the database due to a syntax incompatibility. The data source timed out because the DirectQuery query was too complex or the table too large. A view or table referenced by the DirectQuery model was dropped or modified. The database ran out of connections — DirectQuery can create many concurrent connections. A database maintenance window caused queries to fail while the source was temporarily offline

High severitydata source

Power BI Refresh Error:
DM_ErrorCode_BackEnd_QueryExecutionFailed_DirectQuery

What does this error mean?

A DirectQuery dataset generated a query to the data source that failed to execute. Unlike Import mode, DirectQuery sends live queries on every report interaction, making source stability critical.

Common causes

1The DirectQuery-generated SQL was rejected by the database due to a syntax incompatibility
2The data source timed out because the DirectQuery query was too complex or the table too large
3A view or table referenced by the DirectQuery model was dropped or modified
4The database ran out of connections — DirectQuery can create many concurrent connections
5A database maintenance window caused queries to fail while the source was temporarily offline

How to fix it

1Enable diagnostic logging in Power BI to capture the actual SQL generated by DirectQuery.
2Run the captured SQL directly on the database to reproduce and debug the failure.
3Add aggregations to your Power BI model (composite model) to reduce the complexity of generated DirectQuery SQL.
4Set query timeouts in the dataset options to avoid cascading failures from slow queries.
5Consider switching heavily-queried tables from DirectQuery to Import mode with incremental refresh for better reliability.

Frequently asked questions

Does this error affect multiple datasets at once?

If multiple datasets connect to the same data source, yes — all of them will fail until the source connectivity is restored.

Can this error be caused by a server migration or rename?

Yes — if the server name, database name, or connection string changed (e.g., during a cloud migration), Power BI still holds the old connection details. Update the connection in Power BI Desktop and republish.

Does this error appear in Power BI Desktop?

Sometimes — if you open the .pbix file and attempt a refresh, Desktop will surface the same connection error. This is useful for debugging without affecting the Service dataset.

Will the error resolve automatically once the source is back online?

Only if it was a temporary outage. The next scheduled refresh will succeed automatically. If the connection string changed or credentials expired, manual intervention is needed.

Source · learn.microsoft.com/en-us/power-bi/connect-data/service-gateway-data-sources