10046 not tracing everything?

Good day, all,

We are trying to isolate a query that is assigned a bad query plan, but when we turn on event 10046, the sql is not captured. I have verified that the session (and serial#) are valid, show up in dba_hist_active_session_history and that the event is triggered for this specific session. But even though the sql id (and corresponding plan hash value) are in dba_hist_active_session_history, they are not in the trace file. Under what circumstances will event 10046 not trace a query? I browsed a few metalink notes, but was not able to find one that listed any exceptions. Not that I think it matters much, but the query is not "system" query (ie, gathering dynamic stats), but a good old application query.

charles schultz
oracle dba
aits - adsd
university of illinois

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