Is OraOLEDB provider in .NET unreliable on CLOB fields?

Question

I have a query that seems to be returning the wrong data from the OleDbDataReader. I\'ve included the actual code below (with user id and pass changed). I\'m running on Or

Answer 1

Fantastic !

Had similar problem where a recordset containing two records ( tiff files ) was displaying the first record successfully but giving the error re: argument type on the second record.

Determined that only one dll in the patch for the OLE fix is changed and just replaced this single dll ( OraOLEDBrst11.dll within the oracle client bin directory ).

Works fine now.

Answer 2

That's a strange behavior. The only reference I found in forums to such an issue is this old one, back to Oracle 8!

Debugging our Open Source DB classes in un-managed Delphi code, I found out the same issue! So it sounds not like a DotNet or ADO error, but an issue on the OraOleDB provider side... :(

The BLOBs retrieved from our direct OCI classes just contain all existing BLOB content, whereas the OleDB version does sometimes return NULL, not for all rows!

Sounds definitively like an issue with the provider. I would recommend using direct OCI access (Oracle Native access on DotNet), and do not rely on Oracle's OleDB provider...

I tested this with latest Oracle 11g Client and Server, with 32 bit client under Win64.

Answer 3

Oracle Support has bug 9866728, but that applies to OLEDB provider 11.2.0.1. It has been fixed in the patches listed in document 1272856.1. To access those documents and the patches you need an Oracle Support account.

About Oracle Express 10g, it is known to be an unsupported release (no patch was ever released) with some known bugs - I would not use it for a production application. Joining the Oracle Partner Network will allow you to use development/test license to develop and test against the actual releases, not an outdated (although free...) one.