Expert Oracle Practices p134
SQL> create table tcube as select g1,g2,g3,sum(v1)s1,count(v1)c1,grouping_id(g1,g2,g3)gid from t group by cube(g1,g2,g3);
表已创建。
已用时间:00: 00: 03.72
SQL> select * from table(dbms_xplan.display_cursor(null,null,'ALLSTATS LAST+PEEKED_BINDS -ROWS'));
PLAN_TABLE_OUTPUT
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SQL_ID238m88kmd5xkx, child number 2
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create table tcube as select g1,g2,g3,sum(v1)s1,count(v1)c1,grouping_id(
g1,g2,g3)gid from t group by cube(g1,g2,g3)
Plan hash value: 1684350304
------------------------------------------------------------------
| Id| Operation
| Name |OMem |1Mem | Used-Mem |
------------------------------------------------------------------
| 0 | CREATE TABLE STATEMENT || | |
|
| 1 |LOAD AS SELECT|| 525K| 525K|525K (0)|
| 2 | SORT GROUP BY||60M|2869K| 53M (0)|
| 3 |GENERATE CUBE || | |
|
| 4 | SORT GROUP BY||8912K|1165K| 7921K (0)|
| 5 |TABLE ACCESS FULL | T| | |
|
------------------------------------------------------------------
Note
-----
- Warning: basic plan statistics not available. These are only collected when:
* hint 'gather_plan_statistics' is used for the statement or
* parameter 'statistics_level' is set to 'ALL', at session or system level
已选择24行。
已用时间:00: 00: 00.04
SQL>
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