SQL>
SQL> VARIABLE current_scn NUMBER
SQL> EXECUTE :current_scn := DBMS_FLASHBACK.GET_SYSTEM_CHANGE_NUMBER();
PL/SQL procedure successfully completed.
SQL> PRINT current_scn
CURRENT_SCN
-----------
5547739
SQL>
SQL> EXECUTE DBMS_FLASHBACK.ENABLE_AT_SYSTEM_CHANGE_NUMBER(:current_scn);
BEGIN DBMS_FLASHBACK.ENABLE_AT_SYSTEM_CHANGE_NUMBER(:current_scn); END;
SQL>
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