通过分析SQL语句的执行计划优化SQL（12）（2）

(1) sqlplus > @ ?\rdbms\admin\utlxplan.sql
(2) sqlplus > explain plan set statement_id =’???’
for select ………………

set linesize 150
set pagesize 500
col PLANLINE for a120
SELECT EXECORD EXEC_ORDER, PLANLINE 
FROM (SELECT PLANLINE, ROWNUM EXECORD, ID, RID 
FROM (SELECT PLANLINE, ID, RID, LEV 
FROM (SELECT lpad(' ',2*(LEVEL),rpad(' ',80,'     '))
||OPERATION||'  '||                 -- Operation 
DECODE(OPTIONS,NULL,'','('||OPTIONS || ') ')
||  -- Options 
DECODE(OBJECT_OWNER,null,'','OF '''|| OBJECT_OWNER
||'.')||  -- Owner 
DECODE(OBJECT_NAME,null,'',OBJECT_NAME|| ''' ')
|| -- Object Name 
DECODE(OBJECT_TYPE,null,'','('||OBJECT_TYPE|| ') ')
||  -- Object Type 
DECODE(ID,0,'OPT_MODE:')||       -- Optimizer 
DECODE(OPTIMIZER,null,'','ANALYZED','', OPTIMIZER)|| 
DECODE(NVL(COST,0)+NVL(CARDINALITY,0)+NVL(BYTES,0), 
0,null,' (COST='||TO_CHAR(COST)||',CARD='|| 
TO_CHAR(CARDINALITY)||',BYTES='||TO_CHAR(BYTES)||')') 
PLANLINE, ID, LEVEL LEV, 
(SELECT MAX(ID) 
FROM PLAN_TABLE PL2 
CONNECT BY PRIOR ID = PARENT_ID 
AND PRIOR STATEMENT_ID = STATEMENT_ID 
START WITH ID = PL1.ID 
AND STATEMENT_ID = PL1.STATEMENT_ID) RID 
FROM PLAN_TABLE PL1 
CONNECT BY PRIOR ID = PARENT_ID 
AND PRIOR STATEMENT_ID = STATEMENT_ID 
START WITH ID = 0 
AND STATEMENT_ID = 'aaa') 
ORDER BY RID, -LEV)) 
ORDER BY ID;