Problems with DirectQuery and Oracle Sources - "An error was encountered in the transport layer"

[Ricardo77]

Hello,

Im developing reports in Power BI Desktop (RS - don't think it's too important here) with Live Query connection to SSAS 2017, and SSAS is connected to Oracle sources using Direct Query. 

I would like to know what are the inevitable things to analize, between Oracle and mainly in SSAS and Power BI, that could justify that 40% of the reports sheets fail with message "couldn't load data for this visual, An error was encountered in the transport layer". In DAX studio the message is "error connecting to the server: the connection was either timed out or was lost".

Meanwhile we are trying SQL Server 2019, and in this case the % of errors in sheets grows up to 80%.🙄

Thanks 

[v-yingjl]

Hi @Ricardo77 ,

There is SQL Server Analysis Services (SSAS) instance behind each PBI file (new or existing one). Your error is 99% related to this SSAS engine. 

One of cases can be that your firewall, brandmauer or anti-virus is blocking it. Refer to these links:

1.  https://msdn.microsoft.com/en-us/library/ms174937(v=sql.110).aspx 
2.  https://social.msdn.microsoft.com/Forums/sqlserver/en-US/e3a5f79d-8c7d-40e1-b726-b7bf0dd828d3/a-conn...

In addition, currently the latest version of power bi desktop could get the error when connecting to sql server 2019, we suggest you use the Aug 2020 version of power bi temporarily and try to match the SSAS version and SQL server version to avoid compatibility

Best Regards,
Yingjie Li

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