RunQuery Activity; ORA-12537 Network Session: End of File

I’m getting this error when executing some queries against an Oracle DB. Other querys executed succesfully on the same workflow and DB connection.

Anyway, queries that fail with this oracle error code, ran perfectly fine from Oracle client in the same machine as UiPath Studio.

I did a bit of research and find that can be caused by connection lost or cut by firewall or oracle config. related issues but I don’t think it to be any of those, since fails just with some queries while others run smoothly…

any help?

PD: also found this


Did you try increasing the timeout? looks like the Network timed out

Also is the query very huge?


Hi Anil, thank you for your answer.

I left unused the timeout in the Run Query activity

Besides, the error shows up very quickly after the Run Query activity executes, so I don’t think increasing timeout would help, but will try nonetheless.


Is the query huge or returning huge data?

And did you happen to check the exception details from locals panel by running in debug mode that will help in understanding the error better …generally it might have more info about what exactly errored out


Apparently it is a problem with the CLOB data type in oracle. If selecting a column which is a CLOB column, UiPath Run Query activity returns this ORA-12537 error. Must cast to VARCHAR2. Anyway, Database package may have issues with CLOB types.

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