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Are optimiser hints added by Oracle

edited Dec 8, 2022 8:44AM in Database Tuning (MOSC) 5 commentsAnswered ✓

Hi,

I have a user claiming that he is sending an SQL query to the database with no hints but then when he looks in DBA_HIST_SQLTEXT he is seeing:

SELECT /*+ opt_param('_optimiser_user_auto_indexes' 'on') parallel_index.....

He is using Java, JDBC, Hibernate to send the query to the DB.

I thought that only users can add hints - is it possible there is some mechanism within Oracle that adds hints (not that I see the point of this), or is he missing something on the Java side?

Thanks

Si

Oracle 19C

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