declare
drop_result pls_integer;
begin
drop_result := DBMS_SPM.DROP_SQL_PLAN_BASELINE(
plan_name => '&sql_plan_baseline_name');
dbms_output.put_line(drop_result);
end;
/
You can get the sql baseline from a sql_id from below command:
SELECT sql_handle, plan_name FROM dba_sql_plan_baselines WHERE signature IN
( SELECT exact_matching_signature FROM gv$sql WHERE sql_id='&SQL_ID');