如何修复错误“灾难性故障。无法从链接服务器的 OLE DB 提供程序“OraOLEDB.Oracle”获取行”

Question

I have a SQL Server 2008 R2 64-bit with a linked server to Oracle 12c using OraOLEDB.Oracle provider.

When I fetch data from the Oracle linked server using OPENQUERY, I am receiving the following error message:

The OLE DB provider "OraOLEDB.Oracle" for linked server reported an error. The provider reported an unexpected catastrophic failure.

Cannot fetch a row from OLE DB provider "OraOLEDB.Oracle" for linked server.

In OraOLEDB.Oracle provider options, Allow Inprocess is checked.

This error only happens when I queried all data, but if I add a WHERE clause WHERE ROWNUM <100 to limit to 99 rows, it would go without issue.

This does not happen to other servers with the same environment.

I have tried uncheck/re-check Allow Inprocess, but it didnt work. I tried uninstall the existing Oracle client and reinstall it, and it didnt work either.

Answer 1

Make sure the "Users" group has "Read & execute", "List Folder contents" and "Read" permissions to the complete directory your Oracle Client is installed in. That is what fixed it for me.

I was also having a query work fine in SQLPlus, but as soon as I tried to execute it from Toad using the Linked Server, I would get that "catastrophic failure". I was also not able to see views or tables for the Linked Server from within SSMS. I finally went back to basics, and checked user permissions on the Driver directory, and they were all over the place.
I went to the base folder just off the root of the drive, and checked Security, then went to " Advanced " in that Tab. Then, in the " Advanced Security Settings " Clicked on the " Change Permissions ". Once you do that, there is a check box to " Replace all child object permission entries with inheritable permission entries from this object " Check that box and Click " OK "

I verified the SQLPlus query still worked, then ran all of my test queries that were failing, and they all now gave results. I am also now able to see Tables & Views in SSMS.