What causes UserErrorSqlBulkCopyFailed?

A source value cannot be cast to the target column's data type. A NOT NULL constraint in the target table is violated by null values in the source data. The source has more or fewer columns than the target table mapping expects. A UNIQUE or PRIMARY KEY constraint violation due to duplicate values in the source data. The target table has a computed column or identity column that conflicts with the insert

How do I fix UserErrorSqlBulkCopyFailed?

Check the ADF copy activity error details for the specific SQL constraint or conversion error message.. Enable 'Fault tolerance' in the copy activity to log and skip bad rows without failing the whole pipeline.. Use a staging table as the sink and add a data quality check before merging to the final target.. Add explicit column mappings in the copy activity to control which source columns map to which target columns.. Pre-validate source data with a data flow or a SQL pre-copy script that filters out rows violating the target constraints.

High severitydata source

Power BI Refresh Error:
UserErrorSqlBulkCopyFailed

What does this error mean?

An Azure Data Factory copy activity using bulk insert to write data into SQL Server or Azure SQL Database failed.

Common causes

1A source value cannot be cast to the target column's data type
2A NOT NULL constraint in the target table is violated by null values in the source data
3The source has more or fewer columns than the target table mapping expects
4A UNIQUE or PRIMARY KEY constraint violation due to duplicate values in the source data
5The target table has a computed column or identity column that conflicts with the insert

How to fix it

1Check the ADF copy activity error details for the specific SQL constraint or conversion error message.
2Enable 'Fault tolerance' in the copy activity to log and skip bad rows without failing the whole pipeline.
3Use a staging table as the sink and add a data quality check before merging to the final target.
4Add explicit column mappings in the copy activity to control which source columns map to which target columns.
5Pre-validate source data with a data flow or a SQL pre-copy script that filters out rows violating the target constraints.

Frequently asked questions

Does this error affect all pipeline runs or just the current one?

Depends on the root cause. A persistent misconfiguration fails every run; a transient issue may resolve on retry. Check the run history.

Can this error appear in Azure Data Factory and Microsoft Fabric pipelines?

Yes — the same connector errors appear in both ADF and Fabric Data Factory pipelines.

How do I see the full error detail for an ADF pipeline failure?

In ADF Monitor, click the failed run, then the failed activity. The detail pane shows the error code, message, and sub-error codes.

Will downstream Power BI datasets be affected when an ADF pipeline fails?

Yes — a dataset refreshing after the pipeline will use stale data or fail if the target table was cleared. The Power BI refresh may succeed while serving wrong data.

Official documentation: https://learn.microsoft.com/en-us/azure/data-factory/connector-troubleshoot-sql