Microsoft.Data.Mashup.ValueError.Message Referenced external data source (null) not found. Error...

[adrianczerski]

Can someone help me to understand error? it happens when model is reading from synapse serverless sql pool which is synchronized with lake database. It's not permament error because after some time I can refresh the same model without this issue:

Data source error:
{"error":{"code":"DM_GWPipeline_Gateway_MashupDataAccessError","pbi.error":{"code":"DM_GWPipeline_Gateway_MashupDataAccessError","parameters":{},
"details":[{"code":"DM_ErrorDetailNameCode_UnderlyingErrorCode","detail":{"type":1,"value":"-2147467259"}},
{"code":"DM_ErrorDetailNameCode_UnderlyingErrorMessage","detail":{"type":1,"value":"Microsoft SQL: Referenced external data source \"(null)\" not found.\r\nError reading external metadata."}},
{"code":"DM_ErrorDetailNameCode_UnderlyingHResult","detail":{"type":1,"value":"-2147467259"}},{"code":"Microsoft.Data.Mashup.ErrorCode","detail":{"type":1,"value":"10478"}},
{"code":"Microsoft.Data.Mashup.ValueError.Class","detail":{"type":1,"value":"16"}},{"code":"Microsoft.Data.Mashup.ValueError.DataSourceKind","detail":{"type":1,"value":"SQL"}},
{"code":"Microsoft.Data.Mashup.ValueError.DataSourcePath","detail":{"type":1,"value":"XXXXXXXX-ondemand.sql.azuresynapse.net;XXXX"}},
{"code":"Microsoft.Data.Mashup.ValueError.ErrorCode","detail":{"type":1,"value":"-2146232060"}},{"code":"Microsoft.Data.Mashup.ValueError.Message",
"detail":{"type":1,"value":"Referenced external data source \"(null)\" not found.\r\nError reading external metadata."}},
{"code":"Microsoft.Data.Mashup.ValueError.Number","detail":{"type":1,"value":"12703"}},{"code":"Microsoft.Data.Mashup.ValueError.Reason",
"detail":{"type":1,"value":"DataSource.Error"}},{"code":"Microsoft.Data.Mashup.ValueError.State","detail":{"type":1,"value":"1"}}],"exceptionCulprit":1}}} Table: complaints

It started from a few weeks and It happen for differen datasets in different part of day, some days it doesn't appear like a lottery.

Thanks in advance!

[rajendraongole1 · Accepted solution]

Hi @adrianczerski - The error you're experiencing with your Power BI model when reading from Azure Synapse Serverless SQL Pool, specifically the "Referenced external data source "(null)" not found. Error reading external metadata," is not uncommon with setups involving Synapse, Azure Data Lake, and external data sources. This type of intermittent issue can be due to several factors, including temporary service issues, metadata syncing issues, or limitations with Synapse Serverless SQL Pools.

Since Synapse Serverless SQL Pools work on top of Azure Data Lake storage, sometimes there are delays or connectivity issues when retrieving external metadata. This may cause intermittent failures, especially if the metadata sync between Synapse and Data Lake is delayed.

As a workaround, consider implementing a retry logic in Power BI or Power Automate if this refresh is part of an automated process. A simple retry can sometimes bypass intermittent connectivity or availability issues.