Re: Crazy dynamic sampling?

I’ve experienced this before, the global statistics of the indexes in question were missing.

It is certainly buggy looking behaviour for the dynamic sampling to do full index scans, if you trace the execution you will see (or rather I saw in my case) that the dynamic sampling queries were hinting for full index scans. I didn’t get as far as looking on MOS but I suspect there will be something there.

Are you able to gather/set the statistics at a global level?

Anecdotally, it happened to me while inserting into a table over a DB link, one of the recursive queries during the parse was a select * from table_at_remote, which was pretty strange. Don’t think the issue is limited to this though.

Hope that helps.
Andrew

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