Oracle PL/SQL Tutorial/SQL PLUS Session Environment/AUTOTRACE — различия между версиями

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Текущая версия на 10:03, 26 мая 2010

Autotrace an self join

SQL>
SQL> create table t as select * from all_objects where rownum < 50;
Table created.
SQL>
SQL>
SQL> alter session set sort_area_size = 1024000;
Session altered.
SQL>
SQL> set autotrace on
SQL>
SQL> select *
  2    from t myTable1, t myTable2
  3   where myTable1.object_id = myTable2.object_id
  4  /
OWNER                          OBJECT_NAME                    SUBOBJECT_NAME                  OBJECT_ID DATA_OBJECT_ID
------------------------------ ------------------------------ ------------------------------ ---------- --------------
OBJECT_TYPE         CREATED   LAST_DDL_ TIMESTAMP           STATUS  T G S OWNER
------------------- --------- --------- ------------------- ------- - - - ------------------------------
OBJECT_NAME                    SUBOBJECT_NAME                  OBJECT_ID DATA_OBJECT_ID OBJECT_TYPE      CREATED   LAST_DDL_
------------------------------ ------------------------------ ---------- -------------- ------------------- --------- ---------
TIMESTAMP           STATUS  T G S
------------------- ------- - - -
SYS                            ICOL$                                                                 20              2
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
ICOL$                                                                 20              2 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_USER1                                                               44             44
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_USER1                                                               44             44 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            CON$                                                                  28             28
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
CON$                                                                  28             28 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            UNDO$                                                                 15             15
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
UNDO$                                                                 15             15 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            C_COBJ#                                                               29             29
CLUSTER             07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
C_COBJ#                                                               29             29 CLUSTER          07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_OBJ#                                                                 3              3
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_OBJ#                                                                 3              3 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            PROXY_ROLE_DATA$                                                      25             25
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
PROXY_ROLE_DATA$                                                      25             25 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_IND1                                                                39             39
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_IND1                                                                39             39 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_CDEF2                                                               51             51
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_CDEF2                                                               51             51 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_PROXY_ROLE_DATA$_1                                                  26             26
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_PROXY_ROLE_DATA$_1                                                  26             26 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            FILE$                                                                 17             17
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
FILE$                                                                 17             17 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            UET$                                                                  13              8
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
UET$                                                                  13              8 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_FILE#_BLOCK#                                                         9              9
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_FILE#_BLOCK#                                                         9              9 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_FILE1                                                               41             41
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_FILE1                                                               41             41 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_CON1                                                                48             48
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_CON1                                                                48             48 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_OBJ3                                                                38             38
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_OBJ3                                                                38             38 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_TS#                                                                  7              7
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_TS#                                                                  7              7 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_CDEF4                                                               53             53
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_CDEF4                                                               53             53 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            IND$                                                                  19              2
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
IND$                                                                  19              2 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            SEG$                                                                  14              8
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
SEG$                                                                  14              8 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            C_TS#                                                                  6              6
CLUSTER             07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
C_TS#                                                                  6              6 CLUSTER          07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_FILE2                                                               42             42
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_FILE2                                                               42             42 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            COL$                                                                  21              2
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
COL$                                                                  21              2 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_TS1                                                                 43             43
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_TS1                                                                 43             43 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_UNDO2                                                               35             35
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_UNDO2                                                               35             35 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            CLU$                                                                   5              2
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
CLU$                                                                   5              2 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            PROXY_DATA$                                                           23             23
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
PROXY_DATA$                                                           23             23 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_PROXY_DATA$                                                         24             24
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_PROXY_DATA$                                                         24             24 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_OBJ1                                                                36             36
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_OBJ1                                                                36             36 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_COL2                                                                46             46
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_COL2                                                                46             46 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_OBJ2                                                                37             37
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_OBJ2                                                                37             37 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_CCOL1                                                               54             54
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_CCOL1                                                               54             54 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            TS$                                                                   16              6
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
TS$                                                                   16              6 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            C_FILE#_BLOCK#                                                         8              8
CLUSTER             07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
C_FILE#_BLOCK#                                                         8              8 CLUSTER          07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            C_USER#                                                               10             10
CLUSTER             07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
C_USER#                                                               10             10 CLUSTER          07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_UNDO1                                                               34             34
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_UNDO1                                                               34             34 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            BOOTSTRAP$                                                            56             56
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
BOOTSTRAP$                                                            56             56 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            FET$                                                                  12              6
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
FET$                                                                  12              6 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_TAB1                                                                33             33
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_TAB1                                                                33             33 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            CCOL$                                                                 32             29
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
CCOL$                                                                 32             29 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            USER$                                                                 22             10
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
USER$                                                                 22             10 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_CON2                                                                49             49
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_CON2                                                                49             49 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_COBJ#                                                               30             30
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_COBJ#                                                               30             30 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            OBJ$                                                                  18             18
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
OBJ$                                                                  18             18 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_COL3                                                                47             47
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_COL3                                                                47             47 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            C_OBJ#                                                                 2              2
CLUSTER             07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
C_OBJ#                                                                 2              2 CLUSTER          07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            TAB$                                                                   4              2
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
TAB$                                                                   4              2 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            CDEF$                                                                 31             29
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
CDEF$                                                                 31             29 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_CDEF1                                                               50             50
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_CDEF1                                                               50             50 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N

49 rows selected.

Execution Plan
----------------------------------------------------------
Plan hash value: 2135975663
---------------------------------------------------------------------------
| Id  | Operation          | Name | Rows  | Bytes | Cost (%CPU)| Time     |
---------------------------------------------------------------------------
|   0 | SELECT STATEMENT   |      |    49 | 12544 |     5  (20)| 00:00:01 |
|*  1 |  HASH JOIN         |      |    49 | 12544 |     5  (20)| 00:00:01 |
|   2 |   TABLE ACCESS FULL| T    |    49 |  6272 |     2   (0)| 00:00:01 |
|   3 |   TABLE ACCESS FULL| T    |    49 |  6272 |     2   (0)| 00:00:01 |
---------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
   1 - access("MYTABLE1"."OBJECT_ID"="MYTABLE2"."OBJECT_ID")
Note
-----
   - dynamic sampling used for this statement

Statistics
----------------------------------------------------------
        272  recursive calls
          0  db block gets
         41  consistent gets
          1  physical reads
          0  redo size
       4375  bytes sent via SQL*Net to client
        380  bytes received via SQL*Net from client
          2  SQL*Net roundtrips to/from client
          2  sorts (memory)
          0  sorts (disk)
         49  rows processed
SQL> alter session set sort_area_size = 10240000;
Session altered.
SQL>
SQL> select *
  2    from t myTable1, t myTable2
  3   where myTable1.object_id = myTable2.object_id
  4         and rownum < 50
  5  /
OWNER                          OBJECT_NAME                    SUBOBJECT_NAME                  OBJECT_ID DATA_OBJECT_ID
------------------------------ ------------------------------ ------------------------------ ---------- --------------
OBJECT_TYPE         CREATED   LAST_DDL_ TIMESTAMP           STATUS  T G S OWNER
------------------- --------- --------- ------------------- ------- - - - ------------------------------
OBJECT_NAME                    SUBOBJECT_NAME                  OBJECT_ID DATA_OBJECT_ID OBJECT_TYPE      CREATED   LAST_DDL_
------------------------------ ------------------------------ ---------- -------------- ------------------- --------- ---------
TIMESTAMP           STATUS  T G S
------------------- ------- - - -
SYS                            ICOL$                                                                 20              2
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
ICOL$                                                                 20              2 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_USER1                                                               44             44
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_USER1                                                               44             44 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            CON$                                                                  28             28
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
CON$                                                                  28             28 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            UNDO$                                                                 15             15
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
UNDO$                                                                 15             15 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            C_COBJ#                                                               29             29
CLUSTER             07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
C_COBJ#                                                               29             29 CLUSTER          07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_OBJ#                                                                 3              3
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_OBJ#                                                                 3              3 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            PROXY_ROLE_DATA$                                                      25             25
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
PROXY_ROLE_DATA$                                                      25             25 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_IND1                                                                39             39
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_IND1                                                                39             39 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_CDEF2                                                               51             51
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_CDEF2                                                               51             51 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_PROXY_ROLE_DATA$_1                                                  26             26
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_PROXY_ROLE_DATA$_1                                                  26             26 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            FILE$                                                                 17             17
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
FILE$                                                                 17             17 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            UET$                                                                  13              8
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
UET$                                                                  13              8 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_FILE#_BLOCK#                                                         9              9
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_FILE#_BLOCK#                                                         9              9 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_FILE1                                                               41             41
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_FILE1                                                               41             41 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_CON1                                                                48             48
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_CON1                                                                48             48 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_OBJ3                                                                38             38
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_OBJ3                                                                38             38 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_TS#                                                                  7              7
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_TS#                                                                  7              7 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_CDEF4                                                               53             53
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_CDEF4                                                               53             53 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            IND$                                                                  19              2
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
IND$                                                                  19              2 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            SEG$                                                                  14              8
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
SEG$                                                                  14              8 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            C_TS#                                                                  6              6
CLUSTER             07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
C_TS#                                                                  6              6 CLUSTER          07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_FILE2                                                               42             42
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_FILE2                                                               42             42 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            COL$                                                                  21              2
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
COL$                                                                  21              2 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_TS1                                                                 43             43
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_TS1                                                                 43             43 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_UNDO2                                                               35             35
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_UNDO2                                                               35             35 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            CLU$                                                                   5              2
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
CLU$                                                                   5              2 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            PROXY_DATA$                                                           23             23
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
PROXY_DATA$                                                           23             23 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_PROXY_DATA$                                                         24             24
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_PROXY_DATA$                                                         24             24 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_OBJ1                                                                36             36
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_OBJ1                                                                36             36 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_COL2                                                                46             46
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_COL2                                                                46             46 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_OBJ2                                                                37             37
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_OBJ2                                                                37             37 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_CCOL1                                                               54             54
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_CCOL1                                                               54             54 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            TS$                                                                   16              6
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
TS$                                                                   16              6 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            C_FILE#_BLOCK#                                                         8              8
CLUSTER             07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
C_FILE#_BLOCK#                                                         8              8 CLUSTER          07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            C_USER#                                                               10             10
CLUSTER             07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
C_USER#                                                               10             10 CLUSTER          07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_UNDO1                                                               34             34
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_UNDO1                                                               34             34 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            BOOTSTRAP$                                                            56             56
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
BOOTSTRAP$                                                            56             56 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            FET$                                                                  12              6
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
FET$                                                                  12              6 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_TAB1                                                                33             33
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_TAB1                                                                33             33 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            CCOL$                                                                 32             29
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
CCOL$                                                                 32             29 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            USER$                                                                 22             10
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
USER$                                                                 22             10 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_CON2                                                                49             49
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_CON2                                                                49             49 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_COBJ#                                                               30             30
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_COBJ#                                                               30             30 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            OBJ$                                                                  18             18
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
OBJ$                                                                  18             18 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_COL3                                                                47             47
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_COL3                                                                47             47 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            C_OBJ#                                                                 2              2
CLUSTER             07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
C_OBJ#                                                                 2              2 CLUSTER          07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            TAB$                                                                   4              2
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
TAB$                                                                   4              2 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            CDEF$                                                                 31             29
TABLE               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
CDEF$                                                                 31             29 TABLE            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N
SYS                            I_CDEF1                                                               50             50
INDEX               07-FEB-06 07-FEB-06 2006-02-07:22:10:08 VALID   N N N SYS
I_CDEF1                                                               50             50 INDEX            07-FEB-06 07-FEB-06
2006-02-07:22:10:08 VALID   N N N

49 rows selected.

Execution Plan
----------------------------------------------------------
Plan hash value: 1415706426
----------------------------------------------------------------------------
| Id  | Operation           | Name | Rows  | Bytes | Cost (%CPU)| Time     |
----------------------------------------------------------------------------
|   0 | SELECT STATEMENT    |      |    49 | 12544 |     5  (20)| 00:00:01 |
|*  1 |  COUNT STOPKEY      |      |       |       |            |          |
|*  2 |   HASH JOIN         |      |    49 | 12544 |     5  (20)| 00:00:01 |
|   3 |    TABLE ACCESS FULL| T    |    49 |  6272 |     2   (0)| 00:00:01 |
|   4 |    TABLE ACCESS FULL| T    |    49 |  6272 |     2   (0)| 00:00:01 |
----------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
   1 - filter(ROWNUM<50)
   2 - access("MYTABLE1"."OBJECT_ID"="MYTABLE2"."OBJECT_ID")
Note
-----
   - dynamic sampling used for this statement

Statistics
----------------------------------------------------------
         15  recursive calls
          0  db block gets
         23  consistent gets
          0  physical reads
          0  redo size
       4375  bytes sent via SQL*Net to client
        380  bytes received via SQL*Net from client
          2  SQL*Net roundtrips to/from client
          4  sorts (memory)
          0  sorts (disk)
         49  rows processed
SQL> set autotrace off
SQL>
SQL> drop table t;
Table dropped.
SQL>
SQL>


autotrace count(*)

SQL>
SQL> create table t as select * from all_objects;
Table created.
SQL>
SQL> set autotrace on
SQL> select count(*) from t;
  COUNT(*)
----------
     12586

Execution Plan
----------------------------------------------------------
Plan hash value: 2966233522
-----------------------------------
| Id  | Operation          | Name |
-----------------------------------
|   0 | SELECT STATEMENT   |      |
|   1 |  SORT AGGREGATE    |      |
|   2 |   TABLE ACCESS FULL| T    |
-----------------------------------
Note
-----
   - rule based optimizer used (consider using cbo)

Statistics
----------------------------------------------------------
          1  recursive calls
          0  db block gets
        163  consistent gets
        159  physical reads
          0  redo size
        413  bytes sent via SQL*Net to client
        380  bytes received via SQL*Net from client
          2  SQL*Net roundtrips to/from client
          0  sorts (memory)
          0  sorts (disk)
          1  rows processed
SQL>
SQL>
SQL> set autotrace off
SQL>
SQL> delete from t where owner <> "SCOTT";
12586 rows deleted.
SQL>
SQL> set autotrace on
SQL> select count(*) from t;
  COUNT(*)
----------
         0

Execution Plan
----------------------------------------------------------
Plan hash value: 2966233522
-----------------------------------
| Id  | Operation          | Name |
-----------------------------------
|   0 | SELECT STATEMENT   |      |
|   1 |  SORT AGGREGATE    |      |
|   2 |   TABLE ACCESS FULL| T    |
-----------------------------------
Note
-----
   - rule based optimizer used (consider using cbo)

Statistics
----------------------------------------------------------
          0  recursive calls
          0  db block gets
        163  consistent gets
          0  physical reads
          0  redo size
        410  bytes sent via SQL*Net to client
        380  bytes received via SQL*Net from client
          2  SQL*Net roundtrips to/from client
          0  sorts (memory)
          0  sorts (disk)
          1  rows processed
SQL>
SQL>
SQL> set autotrace off
SQL> alter table t move;
Table altered.
SQL> set autotrace on
SQL> select count(*) from t;
  COUNT(*)
----------
         0

Execution Plan
----------------------------------------------------------
Plan hash value: 2966233522
-----------------------------------
| Id  | Operation          | Name |
-----------------------------------
|   0 | SELECT STATEMENT   |      |
|   1 |  SORT AGGREGATE    |      |
|   2 |   TABLE ACCESS FULL| T    |
-----------------------------------
Note
-----
   - rule based optimizer used (consider using cbo)

Statistics
----------------------------------------------------------
          1  recursive calls
          0  db block gets
          3  consistent gets
          0  physical reads
          0  redo size
        410  bytes sent via SQL*Net to client
        380  bytes received via SQL*Net from client
          2  SQL*Net roundtrips to/from client
          0  sorts (memory)
          0  sorts (disk)
          1  rows processed
SQL>
SQL> set autotrace off
SQL>
SQL> drop table t;
Table dropped.


autotrace merge command

SQL> create table myTable as select * from dba_objects;
Table created.
SQL> delete from myTable where rownum <= 100;
100 rows deleted.
SQL> create table myTable2 as select * from dba_objects;
Table created.
SQL> set autotrace on
SQL> merge into myTable b
  2  using myTable2 o
  3  on (b.owner = o.owner and b.object_name = o.object_name
  4      and
  5      b.subobject_name = o.subobject_name
  6      and
  7      b.object_id = o.object_id)
  8  when matched then update set b.created = o.created
  9  when not matched then insert
 10  values ( o.OWNER ,o.OBJECT_NAME ,o.SUBOBJECT_NAME ,o.OBJECT_ID ,o.DATA_OBJECT_ID
 11          ,o.OBJECT_TYPE ,o.CREATED ,o.LAST_DDL_TIME,o.TIMESTAMP ,o.STATUS,o.TEMPORARY,o.GENERATED
 12          ,o.SECONDARY )
 13  /
13219 rows merged.

Execution Plan
----------------------------------------------------------
Plan hash value: 449939568
-------------------------------------------------------------------------
| Id  | Operation            | Name     | Rows  | Bytes |TempSpc| Cost  |
-------------------------------------------------------------------------
|   0 | MERGE STATEMENT      |          | 13723 |  3832K|       |    99 |
|   1 |  MERGE               | MYTABLE  |       |       |       |       |
|   2 |   VIEW               |          |       |       |       |       |
|*  3 |    HASH JOIN OUTER   |          | 13723 |  2680K|  1504K|    99 |
|   4 |     TABLE ACCESS FULL| MYTABLE2 | 13723 |  1340K|       |    26 |
|   5 |     TABLE ACCESS FULL| MYTABLE  | 13723 |  1340K|       |    26 |
-------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
   3 - access("B"."OBJECT_ID"(+)="O"."OBJECT_ID" AND
              "B"."SUBOBJECT_NAME"(+)="O"."SUBOBJECT_NAME" AND
              "B"."OBJECT_NAME"(+)="O"."OBJECT_NAME" AND "B"."OWNER"(+)="O"."OWN
ER")

Note
-----
   - cpu costing is off (consider enabling it)

Statistics
----------------------------------------------------------
        253  recursive calls
      14050  db block gets
        388  consistent gets
        329  physical reads
    4644528  redo size
        929  bytes sent via SQL*Net to client
       1374  bytes received via SQL*Net from client
          6  SQL*Net roundtrips to/from client
          1  sorts (memory)
          0  sorts (disk)
      13219  rows processed
SQL>
SQL> set autotrace off
SQL> rollback;
Rollback complete.
SQL> set autotrace on
SQL>
SQL> merge into myTable b
  2  using (select * from myTable2) o
  3  on (b.owner = o.owner and b.object_name = o.object_name
  4      and
  5      b.subobject_name = o.subobject_name
  6      and
  7      b.object_id = o.object_id)
  8  when matched then update set b.created = o.created
  9  when not matched then insert
 10  values ( o.OWNER ,o.OBJECT_NAME ,o.SUBOBJECT_NAME ,o.OBJECT_ID ,o.DATA_OBJECT_ID
 11          ,o.OBJECT_TYPE ,o.CREATED ,o.LAST_DDL_TIME,o.TIMESTAMP ,o.STATUS,o.TEMPORARY,o.GENERATED
 12          ,o.SECONDARY )
 13  /
13219 rows merged.

Execution Plan
----------------------------------------------------------
Plan hash value: 449939568
-------------------------------------------------------------------------
| Id  | Operation            | Name     | Rows  | Bytes |TempSpc| Cost  |
-------------------------------------------------------------------------
|   0 | MERGE STATEMENT      |          | 13723 |  3832K|       |    99 |
|   1 |  MERGE               | MYTABLE  |       |       |       |       |
|   2 |   VIEW               |          |       |       |       |       |
|*  3 |    HASH JOIN OUTER   |          | 13723 |  2680K|  1504K|    99 |
|   4 |     TABLE ACCESS FULL| MYTABLE2 | 13723 |  1340K|       |    26 |
|   5 |     TABLE ACCESS FULL| MYTABLE  | 13723 |  1340K|       |    26 |
-------------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
   3 - access("B"."OBJECT_ID"(+)="MYTABLE2"."OBJECT_ID" AND
              "B"."SUBOBJECT_NAME"(+)="MYTABLE2"."SUBOBJECT_NAME" AND
              "B"."OBJECT_NAME"(+)="MYTABLE2"."OBJECT_NAME" AND
              "B"."OWNER"(+)="MYTABLE2"."OWNER")
Note
-----
   - cpu costing is off (consider enabling it)

Statistics
----------------------------------------------------------
          4  recursive calls
      13763  db block gets
        678  consistent gets
          0  physical reads
    4614184  redo size
        929  bytes sent via SQL*Net to client
       1390  bytes received via SQL*Net from client
          6  SQL*Net roundtrips to/from client
          1  sorts (memory)
          0  sorts (disk)
      13219  rows processed
SQL>
SQL> set autotrace off
SQL> rollback;
Rollback complete.
SQL>
SQL> drop table myTable;
Table dropped.
SQL> drop table myTable2;
Table dropped.
SQL>
SQL>
SQL>


autotrace table with/without an index

SQL> create table website
  2  ( hostname       varchar2(10),
  3    upTime             date,
  4    load           number,
  5    other_stats    char(65),
  6    constraint website_pk primary key(hostname,upTime)
  7  )
  8  /
Table created.
SQL>
SQL>
SQL> create table indexedwebsite
  2  ( hostname       varchar2(10),
  3    upTime             date,
  4    load           number,
  5    other_stats    char(65),
  6    constraint indexedwebsite_pk primary key(hostname,upTime)
  7  )
  8  organization index
  9  /
Table created.
SQL>
SQL>
SQL> declare
  2      l_load number;
  3  begin
  4      for l_HOURS in 1 .. 100
  5      loop
  6          for l_HOSTS in 1 .. 100
  7          loop
  8              l_load := dbms_random.random;
  9              insert into website(hostname,upTime,load,other_stats)values("hostnm" || l_hosts, sysdate-(100-l_hours)/24,l_load, "x" );
 10              insert into indexedwebsite(hostname,upTime,load,other_stats)values("hostnm" || l_hosts, sysdate-(100-l_hours)/24,l_load, "x" );
 11          end loop;
 12          commit;
 13      end loop;
 14  end;
 15  /
PL/SQL procedure successfully completed.
SQL>
SQL>
SQL> analyze table website compute statistics;
Table analyzed.
SQL>
SQL>
SQL> analyze table indexedwebsite compute statistics;
Table analyzed.
SQL>
SQL>
SQL> set autotrace on
SQL> select avg(load)
  2    from website
  3   where hostname = "hostnm50"
  4     and upTime >= sysdate-100/24
  5  /
 AVG(LOAD)
----------
45908976.3
1 row selected.

Execution Plan
----------------------------------------------------------
Plan hash value: 757115644
--------------------------------------------------------------
| Id  | Operation          | Name    | Rows  | Bytes | Cost  |
--------------------------------------------------------------
|   0 | SELECT STATEMENT   |         |     1 |    29 |    21 |
|   1 |  SORT AGGREGATE    |         |     1 |    29 |       |
|*  2 |   TABLE ACCESS FULL| WEBSITE |   100 |  2900 |    21 |
--------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
   2 - filter("HOSTNAME"="hostnm50" AND
              "UPTIME">=SYSDATE@!-4.16666666666666666666666666666666666667)
Note
-----
   - cpu costing is off (consider enabling it)

Statistics
----------------------------------------------------------
          1  recursive calls
          0  db block gets
        136  consistent gets
          0  physical reads
          0  redo size
        416  bytes sent via SQL*Net to client
        380  bytes received via SQL*Net from client
          2  SQL*Net roundtrips to/from client
          0  sorts (memory)
          0  sorts (disk)
          1  rows processed
SQL> select avg(load)
  2    from indexedwebsite
  3   where hostname = "hostnm50"
  4     and upTime >= sysdate-100/24
  5  /
 AVG(LOAD)
----------
45908976.3
1 row selected.

Execution Plan
----------------------------------------------------------
Plan hash value: 2378983545
-----------------------------------------------------------------------
| Id  | Operation         | Name              | Rows  | Bytes | Cost  |
-----------------------------------------------------------------------
|   0 | SELECT STATEMENT  |                   |     1 |    29 |     4 |
|   1 |  SORT AGGREGATE   |                   |     1 |    29 |       |
|*  2 |   INDEX RANGE SCAN| INDEXEDWEBSITE_PK |   100 |  2900 |     4 |
-----------------------------------------------------------------------
Predicate Information (identified by operation id):
---------------------------------------------------
   2 - access("HOSTNAME"="hostnm50" AND
              "UPTIME">=SYSDATE@!-4.16666666666666666666666666666666666667)
Note
-----
   - cpu costing is off (consider enabling it)

Statistics
----------------------------------------------------------
          1  recursive calls
          0  db block gets
          4  consistent gets
          0  physical reads
          0  redo size
        416  bytes sent via SQL*Net to client
        380  bytes received via SQL*Net from client
          2  SQL*Net roundtrips to/from client
          0  sorts (memory)
          0  sorts (disk)
          1  rows processed
SQL>
SQL> set autotrace off
SQL>
SQL> drop table website;
Table dropped.
SQL> drop table indexedwebsite;
Table dropped.


Controlling the Report

You can control the report by setting the AUTOTRACE system variable.

  1. SET AUTOTRACE OFF: No AUTOTRACE report is generated(This is the default).
  2. SET AUTOTRACE ON EXPLAIN: The AUTOTRACE report shows only the optimizer execution path.
  3. SET AUTOTRACE ON STATISTICS: The AUTOTRACE report shows only the SQL statement execution statistics.
  4. SET AUTOTRACE ON: The AUTOTRACE report includes both the optimizer execution path and the SQL statement execution statistics.
  5. SET AUTOTRACE TRACEONLY: Like SET AUTOTRACE ON, but suppresses the printing of the user"s query output, if any.

Quote from www.Oracle.ru

29. 22. AUTOTRACE 29. 22. 1. Controlling the Report 29. 22. 2. <A href="/Tutorial/Oracle/0580__SQL-PLUS-Session-Environment/setautotracetraceonlyexplain.htm">set autotrace traceonly explain</a> 29. 22. 3. <A href="/Tutorial/Oracle/0580__SQL-PLUS-Session-Environment/SETAUTOTRACEOFF.htm">SET AUTOTRACE OFF</a> 29. 22. 4. <A href="/Tutorial/Oracle/0580__SQL-PLUS-Session-Environment/Autotraceanselfjoin.htm">Autotrace an self join</a> 29. 22. 5. <A href="/Tutorial/Oracle/0580__SQL-PLUS-Session-Environment/autotracecount.htm">autotrace count(*)</a> 29. 22. 6. <A href="/Tutorial/Oracle/0580__SQL-PLUS-Session-Environment/autotracemergecommand.htm">autotrace merge command</a> 29. 22. 7. <A href="/Tutorial/Oracle/0580__SQL-PLUS-Session-Environment/autotracetablewithwithoutanindex.htm">autotrace table with/without an index</a>

SET AUTOTRACE OFF

SQL>
SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    ID                 VARCHAR2(4 BYTE)         NOT NULL primary key,
  3    First_Name         VARCHAR2(10 BYTE),
  4    Last_Name          VARCHAR2(10 BYTE),
  5    Start_Date         DATE,
  6    End_Date           DATE,
  7    Salary             Number(8,2),
  8    City               VARCHAR2(10 BYTE),
  9    Description        VARCHAR2(15 BYTE)
 10  )
 11  /
Table created.
SQL>
SQL> -- prepare data
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2               values ("01","Jason",    "Martin",  to_date("19960725","YYYYMMDD"), to_date("20060725","YYYYMMDD"), 1234.56, "Toronto",  "Programmer")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("02","Alison",   "Mathews", to_date("19760321","YYYYMMDD"), to_date("19860221","YYYYMMDD"), 6661.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("03","James",    "Smith",   to_date("19781212","YYYYMMDD"), to_date("19900315","YYYYMMDD"), 6544.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("04","Celia",    "Rice",    to_date("19821024","YYYYMMDD"), to_date("19990421","YYYYMMDD"), 2344.78, "Vancouver","Manager")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("05","Robert",   "Black",   to_date("19840115","YYYYMMDD"), to_date("19980808","YYYYMMDD"), 2334.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("06","Linda",    "Green",   to_date("19870730","YYYYMMDD"), to_date("19960104","YYYYMMDD"), 4322.78,"New York",  "Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("07","David",    "Larry",   to_date("19901231","YYYYMMDD"), to_date("19980212","YYYYMMDD"), 7897.78,"New York",  "Manager")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("08","James",    "Cat",     to_date("19960917","YYYYMMDD"), to_date("20020415","YYYYMMDD"), 1232.78,"Vancouver", "Tester")
  3  /
1 row created.
SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /

ID   FIRST_NAME           LAST_NAME            START_DAT END_DATE      SALARY CITY       DESCRIPTION
---- -------------------- -------------------- --------- --------- ---------- ---------- ---------------
01   Jason                Martin               25-JUL-96 25-JUL-06    1234.56 Toronto    Programmer
02   Alison               Mathews              21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
03   James                Smith                12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia                Rice                 24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
05   Robert               Black                15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
06   Linda                Green                30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David                Larry                31-DEC-90 12-FEB-98    7897.78 New York   Manager

ID   FIRST_NAME           LAST_NAME            START_DAT END_DATE      SALARY CITY       DESCRIPTION
---- -------------------- -------------------- --------- --------- ---------- ---------- ---------------
08   James                Cat                  17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
8 rows selected.
SQL>
SQL> set autotrace traceonly explain
SQL>
SQL> select * from employee;
Execution Plan
----------------------------------------------------------
Plan hash value: 2119105728
------------------------------------------------------------------------------
| Id  | Operation         | Name     | Rows  | Bytes | Cost (%CPU)| Time     |
------------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |          |     8 |   520 |     2   (0)| 00:00:01 |
|   1 |  TABLE ACCESS FULL| EMPLOYEE |     8 |   520 |     2   (0)| 00:00:01 |
------------------------------------------------------------------------------
Note
-----
   - dynamic sampling used for this statement
SQL>
SQL> analyze table employee compute statistics;
Table analyzed.
SQL>
SQL> select * from employee;
Execution Plan
----------------------------------------------------------
Plan hash value: 2119105728
------------------------------------------------------------------------------
| Id  | Operation         | Name     | Rows  | Bytes | Cost (%CPU)| Time     |
------------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |          |     8 |   376 |     2   (0)| 00:00:01 |
|   1 |  TABLE ACCESS FULL| EMPLOYEE |     8 |   376 |     2   (0)| 00:00:01 |
------------------------------------------------------------------------------
SQL>
SQL> SET AUTOTRACE OFF
SQL>
SQL>
SQL>
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.


set autotrace traceonly explain

SQL>
SQL>
SQL> -- create demo table
SQL> create table Employee(
  2    ID                 VARCHAR2(4 BYTE)         NOT NULL primary key,
  3    First_Name         VARCHAR2(10 BYTE),
  4    Last_Name          VARCHAR2(10 BYTE),
  5    Start_Date         DATE,
  6    End_Date           DATE,
  7    Salary             Number(8,2),
  8    City               VARCHAR2(10 BYTE),
  9    Description        VARCHAR2(15 BYTE)
 10  )
 11  /
Table created.
SQL>
SQL> -- prepare data
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2               values ("01","Jason",    "Martin",  to_date("19960725","YYYYMMDD"), to_date("20060725","YYYYMMDD"), 1234.56, "Toronto",  "Programmer")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("02","Alison",   "Mathews", to_date("19760321","YYYYMMDD"), to_date("19860221","YYYYMMDD"), 6661.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("03","James",    "Smith",   to_date("19781212","YYYYMMDD"), to_date("19900315","YYYYMMDD"), 6544.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("04","Celia",    "Rice",    to_date("19821024","YYYYMMDD"), to_date("19990421","YYYYMMDD"), 2344.78, "Vancouver","Manager")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary,  City,       Description)
  2                values("05","Robert",   "Black",   to_date("19840115","YYYYMMDD"), to_date("19980808","YYYYMMDD"), 2334.78, "Vancouver","Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("06","Linda",    "Green",   to_date("19870730","YYYYMMDD"), to_date("19960104","YYYYMMDD"), 4322.78,"New York",  "Tester")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("07","David",    "Larry",   to_date("19901231","YYYYMMDD"), to_date("19980212","YYYYMMDD"), 7897.78,"New York",  "Manager")
  3  /
1 row created.
SQL> insert into Employee(ID,  First_Name, Last_Name, Start_Date,                     End_Date,                       Salary, City,        Description)
  2                values("08","James",    "Cat",     to_date("19960917","YYYYMMDD"), to_date("20020415","YYYYMMDD"), 1232.78,"Vancouver", "Tester")
  3  /
1 row created.
SQL>
SQL>
SQL>
SQL> -- display data in the table
SQL> select * from Employee
  2  /

ID   FIRST_NAME           LAST_NAME            START_DAT END_DATE      SALARY CITY       DESCRIPTION
---- -------------------- -------------------- --------- --------- ---------- ---------- ---------------
01   Jason                Martin               25-JUL-96 25-JUL-06    1234.56 Toronto    Programmer
02   Alison               Mathews              21-MAR-76 21-FEB-86    6661.78 Vancouver  Tester
03   James                Smith                12-DEC-78 15-MAR-90    6544.78 Vancouver  Tester
04   Celia                Rice                 24-OCT-82 21-APR-99    2344.78 Vancouver  Manager
05   Robert               Black                15-JAN-84 08-AUG-98    2334.78 Vancouver  Tester
06   Linda                Green                30-JUL-87 04-JAN-96    4322.78 New York   Tester
07   David                Larry                31-DEC-90 12-FEB-98    7897.78 New York   Manager

ID   FIRST_NAME           LAST_NAME            START_DAT END_DATE      SALARY CITY       DESCRIPTION
---- -------------------- -------------------- --------- --------- ---------- ---------- ---------------
08   James                Cat                  17-SEP-96 15-APR-02    1232.78 Vancouver  Tester
8 rows selected.
SQL>
SQL> set autotrace traceonly explain
SQL>
SQL> select * from employee;
Execution Plan
----------------------------------------------------------
Plan hash value: 2119105728
------------------------------------------------------------------------------
| Id  | Operation         | Name     | Rows  | Bytes | Cost (%CPU)| Time     |
------------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |          |     8 |   520 |     2   (0)| 00:00:01 |
|   1 |  TABLE ACCESS FULL| EMPLOYEE |     8 |   520 |     2   (0)| 00:00:01 |
------------------------------------------------------------------------------
Note
-----
   - dynamic sampling used for this statement
SQL>
SQL> analyze table employee compute statistics;
Table analyzed.
SQL>
SQL> select * from employee;
Execution Plan
----------------------------------------------------------
Plan hash value: 2119105728
------------------------------------------------------------------------------
| Id  | Operation         | Name     | Rows  | Bytes | Cost (%CPU)| Time     |
------------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |          |     8 |   376 |     2   (0)| 00:00:01 |
|   1 |  TABLE ACCESS FULL| EMPLOYEE |     8 |   376 |     2   (0)| 00:00:01 |
------------------------------------------------------------------------------
SQL>
SQL> SET AUTOTRACE OFF
SQL>
SQL>
SQL>
SQL>
SQL>
SQL> -- clean the table
SQL> drop table Employee
  2  /
Table dropped.