通过分析SQL语句的执行计划优化SQL（12）

SQL> set autotrace on
SQL> select * from dual;

SQL> set autotrace traceonly

(1）在要分析的用户下：
SQLplus > @ ?
dbmsadminutlxplan.SQL
(2) 用sys用户登陆
SQLplus > @ ?SQLplusadminplustrce.SQL
SQLplus > grant plustrace to user_name; 
 - - user_name是上面所说的分析用户

(1) SQLplus > @ ?
dbmsadminutlxplan.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;