How to use the SQL Tuning Advisor feature in Oracle SQL Developer
First execute some codes ..
ALTER system SET CONTROL_MANAGEMENT_PACK_ACCESS='DIAGNOSTIC+TUNING';
GRANT advisor, administer SQL tuning SET,SELECT any dictionary TO &USER;
GRANT advisor to &USER;
GRANT administer sql tuning set to &USER;
EXEC DBMS_STATS.DELETE_SCHEMA_STATS ('&USER');
And show this toturial to help you
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