2.filter --过滤,如not in、min函数等容易产生 Has a number of different meanings, used to indicate partition elimination, may also indicate an actual filter step where one row source is filtering, another, functions such as min may introduce filter steps into query plans. 3.view --视图,大都...
Introduced in 7.3 and requires V733_PLANS_ENABLED=TRUE and CBO, may be hinted using INDEX_FFS hint, uses multiblock i/o, can be executed in parallel, can be used to access second column of concatenated indexes. This is because we are selecting all of the index. ...
('plan_table',null,'typical -cost -bytes')); Figure 6: Customized TYPICAL plan with suppressed options COST and BYTES The Note Section In addition to the plan and the predicate information, the DBMS_XPLAN package displays additional information in the NOTE section, such as when dynamic ...
2.filter--过滤,如not in、min函数等容易产生 Has a number of different meanings, used to indicate partition elimination, may also indicate an actual filter step where one row source is filtering, another, functions such as min may introduce filter steps into query plans. 3.view--视图,大都由...
_name from Educba_articles table and the information of writer_id and writer_name from the table Educba_writers. For this, we can make the use of EXPLAIN command to understand the query plan and flow of execution of this select query that will be followed by the DBMS internally in Red...
The statement in Example 12-4 displays the execution plans. Example 12-4 Statement to display the EXPLAIN PLAN SELECT PLAN_TABLE_OUTPUT FROM TABLE(DBMS_XPLAN.DISPLAY(NULL, 'statement_id','BASIC')); Examples of the output from this statement are shown in Example 12-5 and Example 12-6. ...
SQL coding help Query 1: Which guest(s) (only list the guestNo) have stayed in both hotelNo 2 and hotelNo 4? Query 2: which hotels (only list the hotel number) do not have family rooms? Query 3: Wh What is the use of force ...
SQL> select * from table(dbms_xplan.display); PLAN_TABLE_OUTPUT --- --- Plan hash value: 2498281325 --- --- | Id | Operation | Name | Rows | Bytes | Cost (%CPU)| --
You may keep multiple execution plans in the plan table by assigning each a unique statement_id. Or you may choose to delete the rows from the plan table after you are finished looking at the execution plan. You can also roll back an EXPLAIN PLAN statement in order to remove the ...
1.setautotraceon2.explain planforsql语句;selectplan_table_outputfromtable(dbms_xplan.display());3.通过第3方工具,如plsql developer(f5查看执行计划)、toad等; 三、看懂执行计划 1.执行计划中字段解释 SQL> select * from scott.emp a,scott.emp b where a.empno=b.mgr; ...