Help with ORA-08176 please

Hi

Yesterday a report was running for an hour or so, when the user called and asked why it was taking so long.
I found I needed to create an index so I did.

CREATE INDEX .... NOLOGGING;
ALTER INDEX ... LOGGING; I thought creating the index with NOLOGGING would be a good thing since this was a pretty large table, and the index creation would run faster.

But the report program stopped abruptly at some point with the message

08176, 00000, consistent read failure; rollback data not available

// *Cause: Encountered data changed by an operation that does not generate
// rollback data : create index, direct load or discrete transaction.
// *Action: In read/write transactions, retry the intended operation. Read
// only transactions must be restarted.

Can you explain why a READ transaction would suffer from this (CREATE INDEX... NOLOGGING) ?
To me, Oracle should just start using the index next time it executes the problem request again, following index creation. The request that benefitted from the new index is executed hundreds of time in that report.

After restarting the report program it took only 2 minutes to run.

Thanks

-- 
Syltrem

OpenVMS 7.3-1 + Oracle 8.1.7.4
http://pages.infinit.net/syltrem (OpenVMS related web site, en français)
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