dbms_xplan.display_cursor包与ADVANCED ALLSTATS LAST PEEKED_BINDS区别是什么，很多新手对此不是很清楚，为了帮助大家解决这个难题，下面小编将为大家详细讲解，有这方面需求的人可以来学习下，希望你能有所收获。
结论1：使用ALL LAST比typical多了Query Block Name / Object
Alias和Column Projection Information（列的信息）
结论2：ADVANCED ALLSTATS LAST PEEKED_BINDS比ALL LAST多了这些内容：outline和NOTE，当然如果使用了绑定变量的话，还有绑定变量信息
结论3：一般来说ALL LAST就已经够用了。
使用一个不使用绑定变量的语句来做对比试验：
select /*weiwei*/ e.ename,d.dname from scott.emp e,scott.dept d where
e.deptno=d.deptno;
SQL> SELECT *
FROM table (DBMS_XPLAN.DISPLAY_CURSOR);
PLAN_TABLE_OUTPUT
——————————————————————————————————————————————————————————————————–
SQL_ID 1qwpbwszr5hwb,
child number 0
————————————-
select /*weiwei*/ e.ename,d.dname from
scott.emp e,scott.dept d where
e.deptno=d.deptno
Plan hash value: 844388907
—————————————————————————————-
| Id
|
Operation | Name
| Rows | Bytes | Cost (%CPU)|
Time |
—————————————————————————————-
|
0 | SELECT
STATEMENT
| |
| | 6
(100)| |
|
1 | MERGE
JOIN | |
14 | 308 |
6 (17)| 00:00:01 |
|
2 | TABLE ACCESS BY INDEX ROWID|
DEPT | 4 |
52 |
2 (0)| 00:00:01 |
|
3 | INDEX FULL
SCAN | PK_DEPT | 4 |
|
1 (0)| 00:00:01 |
|*
4 | SORT
JOIN | |
14 | 126 |
4 (25)| 00:00:01 |
|
5 | TABLE ACCESS
FULL | EMP
| 14 | 126 |
3 (0)| 00:00:01 |
—————————————————————————————-
Predicate Information (identified by
operation id):
—————————————————
4 –
access("E"."DEPTNO"="D"."DEPTNO")
filter("E"."DEPTNO"="D"."DEPTNO")
24 rows selected.
select
sql_id,CHILD_NUMBER,sql_text
from v$SQL where sql_text like '%weiwei%' and sql_text not like '%like%';
获得SQL_id为1qwpbwszr5hwb,CHILD_NUMBER为0
select * from table(dbms_xplan.display_cursor('1qwpbwszr5hwb',null,'ALL LAST'));
SQL> select *
from table(dbms_xplan.display_cursor('1qwpbwszr5hwb',null,'ALL LAST'));
PLAN_TABLE_OUTPUT
——————————————————————————————————————————————————————————————————–
SQL_ID 1qwpbwszr5hwb,
child number 0
————————————-
select /*weiwei*/
e.ename,d.dname from scott.emp e,scott.dept d where
e.deptno=d.deptno
Plan hash value:
844388907
—————————————————————————————-
| Id |
Operation | Name
| Rows | Bytes | Cost (%CPU)|
Time |
—————————————————————————————-
| 0 | SELECT
STATEMENT
| |
| | 6
(100)| |
| 1 |
MERGE
JOIN | |
14 | 308 |
6 (17)| 00:00:01 |
| 2 |
TABLE ACCESS BY INDEX ROWID| DEPT
| 4 | 52 |
2 (0)| 00:00:01 |
| 3 |
INDEX FULL SCAN | PK_DEPT | 4 |
|
1 (0)| 00:00:01 |
|* 4 |
SORT
JOIN | |
14 | 126 |
4 (25)| 00:00:01 |
| 5 |
TABLE ACCESS FULL | EMP
| 14 | 126 |
3 (0)| 00:00:01 |
—————————————————————————————-
Query
Block Name / Object Alias (identified by operation id):
————————————————————-
1 – SEL$1
2 – SEL$1 / D@SEL$1
3 – SEL$1 / D@SEL$1
5 – SEL$1 / E@SEL$1
Predicate
Information (identified by operation id):
—————————————————
4 –
access("E"."DEPTNO"="D"."DEPTNO")
filter("E"."DEPTNO"="D"."DEPTNO")
Column
Projection Information (identified by operation id):
———————————————————–
1 –
"D"."DNAME"[VARCHAR2,14],
"E"."ENAME"[VARCHAR2,10]
2 –
"D"."DEPTNO"[NUMBER,22],
"D"."DNAME"[VARCHAR2,14]
3 – "D".ROWID[ROWID,10],
"D"."DEPTNO"[NUMBER,22]
4 – (#keys=1)
"E"."DEPTNO"[NUMBER,22],
"E"."ENAME"[VARCHAR2,10]
5 –
"E"."ENAME"[VARCHAR2,10],
"E"."DEPTNO"[NUMBER,22]
41 rows selected.
结论1：使用ALL LAST比typical多了Query Block Name / Object
Alias和Column Projection Information（列的信息）
再对比ALL LAST与ADVANCED ALLSTATS LAST PEEKED_BINDS
最后最全的是65行
select
* from table(dbms_xplan.display_cursor('1qwpbwszr5hwb',0,'ADVANCED ALLSTATS LAST PEEKED_BINDS'));
SQL> select *
from table(dbms_xplan.display_cursor('1qwpbwszr5hwb',0,'ADVANCED ALLSTATS LAST
PEEKED_BINDS'));
PLAN_TABLE_OUTPUT
——————————————————————————————————————————————————————————————————–
SQL_ID 1qwpbwszr5hwb,
child number 0
————————————-
select /*weiwei*/
e.ename,d.dname from scott.emp e,scott.dept d where
e.deptno=d.deptno
Plan hash value:
844388907
——————————————————————————————————————–
| Id |
Operation | Name
| E-Rows |E-Bytes| Cost (%CPU)|
E-Time | OMem |
1Mem | Used-Mem |
——————————————————————————————————————–
| 0 | SELECT
STATEMENT
| | | | 6
(100)| | | | |
| 1 |
MERGE
JOIN | |
14 | 308 | 6 (17)|
00:00:01
| | | |
| 2 |
TABLE ACCESS BY INDEX ROWID| DEPT
| 4 | 52 |
2 (0)| 00:00:01
| | | |
| 3 |
INDEX FULL SCAN | PK_DEPT | 4 | | 1
(0)| 00:00:01
| | | |
|* 4 |
SORT
JOIN | |
14 | 126 | 4 (25)|
00:00:01 | 2048 | 2048 |
2048 (0)|
| 5 |
TABLE ACCESS FULL | EMP
| 14 | 126 |
3 (0)| 00:00:01
| | | |
——————————————————————————————————————–
Query Block Name /
Object Alias (identified by operation id):
————————————————————-
1 – SEL$1
2 – SEL$1 / D@SEL$1
3 – SEL$1 / D@SEL$1
5 – SEL$1 / E@SEL$1
Outline
Data
————-
/*+
BEGIN_OUTLINE_DATA
IGNORE_OPTIM_EMBEDDED_HINTS
OPTIMIZER_FEATURES_ENABLE('11.2.0.3')
DB_VERSION('11.2.0.3')
OPT_PARAM('query_rewrite_enabled'
'false')
ALL_ROWS
OUTLINE_LEAF(@"SEL$1")
INDEX(@"SEL$1"
"D"@"SEL$1" ("DEPT"."DEPTNO"))
FULL(@"SEL$1"
"E"@"SEL$1")
LEADING(@"SEL$1"
"D"@"SEL$1" "E"@"SEL$1")
USE_MERGE(@"SEL$1"
"E"@"SEL$1")
END_OUTLINE_DATA
*/
Predicate
Information (identified by operation id):
—————————————————
4 –
access("E"."DEPTNO"="D"."DEPTNO")
filter("E"."DEPTNO"="D"."DEPTNO")
Column Projection
Information (identified by operation id):
———————————————————–
1 –
"D"."DNAME"[VARCHAR2,14],
"E"."ENAME"[VARCHAR2,10]
2 –
"D"."DEPTNO"[NUMBER,22],
"D"."DNAME"[VARCHAR2,14]
3 – "D".ROWID[ROWID,10],
"D"."DEPTNO"[NUMBER,22]
4 – (#keys=1)
"E"."DEPTNO"[NUMBER,22],
"E"."ENAME"[VARCHAR2,10]
5 –
"E"."ENAME"[VARCHAR2,10],
"E"."DEPTNO"[NUMBER,22]
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
rows selected.
结论2：ADVANCED ALLSTATS LAST PEEKED_BINDS比ALL LAST多了这些内容：outline和NOTE，当然如果使用了绑定变量的话，还有绑定变量信息
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