内容摘要：复制select*fromdual; Planhashvalue:272002086 ---------------------------------

真实复制select * from dual;   Plan hash value: 272002086   -------------------------------------------------------------------------- | Id  | Operation         | Name | Rows  | Bytes | Cost (%CPU)| Time     |   -------------------------------------------------------------------------- |   0 | SELECT STATEMENT  |      |     1 |     2 |     2   (0)| 00:00:01 |   |   1 |  TABLE ACCESS FULL| DUAL |     1 |     2 |     2   (0)| 00:00:01 |  1.2.3.4.5.6.7.8.9.