exec dbms_stats.gather_database_stats(ESTIMATE_PERCENT=>100, method_opt => 'FOR ALL INDEXED COLUMNS SIZE AUTO', cascade=>true, degree=>120);

在12c和19c中,想要启用资源管理,必须先把并发收集统计信息禁用。
alter system set resource_manager_plan='default_plan' scope=spfile sid='*';
select dbms_stats.get_prefs('CONCURRENT') from dual; --若无true
exec dbms_stats.set_global_prefs('CONCURRENT','FALSE');
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