Nologging changes to LOB's

Hi,
We created a standby database and then started using Dataguard to maintain
and monitor it. Then one day Dataguard sent out an alert that a nologging change had occurred on the production database. After a while I found out about the recording of these changes in V$DATAFILE and that in fact such nologging changes had occurred before we had Dataguard up and running.

So we duplicated the standby and opened it up in normal mode and ran a series of "analyze ... validate structure" commands and a "analyze schema" to generate statistics, as according to a Note on Metalink, these command should error when they come across blocks which have had nologging operations. But they all worked OK.

All of the nologging changes are being recorded for datafiles that support tablespaces that contain LOBs, in the main CLOB's, but we have also seen this happen to a BLOB which is part of an InterMedia Text index! I am not getting anything sensible out of Oracle.

We really want to know why these nologging changes happen, when only temporary objects in the database are nologging and we have no nologging operations in our code. So if anyone out there knows, please share.

Thanks

Pete

[END] Received on Fri May 03 2002 - 03:31:02 CDT