SQL> declare
  2   v int;
  3   begin
  4    select count(*) into v from t1;
  5    dbms_output.put_line('before insert '||v);
  6  --
  7    insert into t1 values(0,0);
  8    select count(*) into v from t1;
  9    dbms_output.put_line('after insert '||v);
 10  --
 11    execute immediate 
 12       'CREATE PRIVATE TEMPORARY TABLE ORA$PTT_TEST_TBL '
 13    || 'ON COMMIT DROP DEFINITION '
 14    || 'AS SELECT * FROM DUAL CONNECT BY LEVEL <= 21';
 15    execute immediate 'select count(*) from ORA$PTT_TEST_TBL' into v;
 16    dbms_output.put_line('PRIVATE TEMPORARY '||v);
 17  --  execute immediate 'truncate table t2';
 18  --
 19    select count(*) into v from t1;
 20    dbms_output.put_line('before rollback '||v);
 21  --
 22    rollback;
 23    select count(*) into v from t1;
 24    dbms_output.put_line('after rollback '||v);
 25   end;
 26  /
before insert 0
after insert 1
PRIVATE TEMPORARY 21
before rollback 1
after rollback 0

PL/SQL procedure successfully completed.

SQL> select count(*) from ORA$PTT_TEST_TBL;

Error starting at line : 36 in command -
select count(*) from ORA$PTT_TEST_TBL
Error at Command Line : 36 Column : 22
Error report -
 SQL Error: ORA-00942: таблица или представление пользователя не существует
00942. 00000 -  "table or view does not exist"

ON COMMIT PRESERVE DEFINITION 

. . .
 10  --
 11    execute immediate 
 12       'CREATE PRIVATE TEMPORARY TABLE ORA$PTT_TEST_TBL '
 13    || 'ON COMMIT PRESERVE DEFINITION '
 14    || 'AS SELECT * FROM DUAL CONNECT BY LEVEL <= 21';
 15    execute immediate 'select count(*) from ORA$PTT_TEST_TBL' into v;
 16    dbms_output.put_line('PRIVATE TEMPORARY '||v);
 17  --  execute immediate 'truncate table t2';
 18  --
 19    select count(*) into v from t1;
 20    dbms_output.put_line('before rollback '||v);
 21  --
 22    rollback;
 23    select count(*) into v from t1;
 24    dbms_output.put_line('after rollback '||v);
 25   end;
 26  /
before insert 0
after insert 1
PRIVATE TEMPORARY 21
before rollback 1
after rollback 0

PL/SQL procedure successfully completed.

SQL> select count(*) from ORA$PTT_TEST_TBL;

  COUNT(*)
----------
        21

SQL> CREATE PRIVATE TEMPORARY TABLE ora$ptt_test_tbl(
  2     n NUMBER
  3   , dt DATE)
  4  ON COMMIT PRESERVE DEFINITION
  5  ;
Private TEMPORARY created.

SQL> INSERT INTO ora$ptt_test_tbl(n, dt)
  2  SELECT LEVEL, SYSDATE FROM DUAL CONNECT BY LEVEL <= 2;
2 rows inserted.

SQL> COMMIT;
Commit complete.

SQL> SELECT * FROM ora$ptt_test_tbl;

         N DT                 
---------- -------------------
         1 12.12.2021 00:37:00
         2 12.12.2021 00:37:00

SQL> -- Временная задержка
SQL> WITH t AS (SELECT level AS n FROM dual CONNECT BY LEVEL <= 10000) SELECT COUNT(*) FROM t A, t B;

  COUNT(*)
----------
 100000000

SQL> INSERT INTO ora$ptt_test_tbl(n, dt)
  2  SELECT LEVEL+10, SYSDATE FROM DUAL CONNECT BY LEVEL <= 1;
1 row inserted.

SQL> SELECT * FROM ora$ptt_test_tbl;

         N DT                 
---------- -------------------
         1 12.12.2021 00:37:00
         2 12.12.2021 00:37:00
        11 12.12.2021 00:37:05

SQL> ROLLBACK;
Rollback complete.

SQL> SELECT * FROM ora$ptt_test_tbl;

         N DT                 
---------- -------------------
         1 12.12.2021 00:37:00
         2 12.12.2021 00:37:00