Transitivity,所谓的传递性，如下：
SQL> select ... from T1, T2
2  where  T1.col1 = T2.col1
3  and    T1.col1 = 100;

等价于：

SQL> select ... from T1, T2
2  where  T1.col1 = T2.col
3  and    T1.col1 = 100
4  and    T2.col1 = 100;

测试如下：

SQL> desc t1;
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------
 A                                                  NUMBER(10)

SQL> desc t2;
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------
 A                                                  NUMBER(10)

SQL> select table_name,index_name,column_name,column_position from user_ind_columns
  2  where table_name in('T1','T2');

TABLE_NAME                     INDEX_NAME                     COLUMN_NAME                    COLUMN_POSITION
------------------------------ ------------------------------ ------------------------------ ---------------
T1                             IDX_T1                         A                                            1
T2                             IDX_T2                         A                                            1

SQL> set autot on
SQL> select * from t1,t2 where t1.a=t2.a and t1.a=1000;

         A          A
---------- ----------
      1000       1000

Execution Plan
----------------------------------------------------------
Plan hash value: 3652879785

-------------------------------------------------------------------------------
| Id  | Operation            | Name   | Rows  | Bytes | Cost (%CPU)| Time     |
-------------------------------------------------------------------------------
|   0 | SELECT STATEMENT     |        |     1 |     8 |     5   (0)| 00:00:01 |
|   1 |  MERGE JOIN CARTESIAN|        |     1 |     8 |     5   (0)| 00:00:01 |
|*  2 |   INDEX RANGE SCAN   | IDX_T1 |     1 |     4 |     3   (0)| 00:00:01 |
|   3 |   BUFFER SORT        |        |     1 |     4 |     2   (0)| 00:00:01 |
|*  4 |    INDEX RANGE SCAN  | IDX_T2 |     1 |     4 |     2   (0)| 00:00:01 |
-------------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   2 - access("T1"."A"=1000)
   4 - access("T2"."A"=1000)

可以看到，   4 - access("T2"."A"=1000)这一行是优化器执行了Transitivity的结果。