GS-PON数据库分区列范围查询优化案例

查询慢的SQL：

with p as(
     select np.nodecode , np.nodename, d.deviceid, d.devicename, d.loopaddress, p.respara, p.rxcrcerror, p.txcrcerror
     from   perf_t_ponport p,device d, node c,node np
     where  p.resid = d.deviceid
     and    d.nodecode = c.nodecode 
     and    c.citynodecode = np.nodecode
     and    c.nodecode in (SELECT S.NODECODE FROM SINGLEUSERNODEAUTH S WHERE S.NETUSERID = 'admin' AND S.AUTHTYPE = 'VIEW')
     and    d.changetype = 0
     and    p.coltime between trunc(sysdate-1,'dd') and   trunc(sysdate,'dd')
     and    p.rxcrcerror is not null
     and    p.rxcrcerror >0 
    order by   p.rxcrcerror desc
)
select *
from   p
where rownum <=10

这个SQL执行花费了1分钟24秒，需要优化。

查看执行计划：

SQL> explain plan for with p as(
  2       select np.nodecode , np.nodename, d.deviceid, d.devicename, d.loopaddress, p.respara, p.rx
crcerror, p.txcrcerror
  3       from   perf_t_ponport p,device d, node c,node np
  4       where  p.resid = d.deviceid
  5       and    d.nodecode = c.nodecode 
  6       and    c.citynodecode = np.nodecode
  7       and    c.nodecode in (SELECT S.NODECODE FROM SINGLEUSERNODEAUTH S WHERE S.NETUSERID = 'adm
in' AND S.AUTHTYPE = 'VIEW')
  8       and    d.changetype = 0
  9       and    p.coltime between trunc(sysdate-1,'dd') and   trunc(sysdate,'dd')
 10       and    p.rxcrcerror is not null
 11       and    p.rxcrcerror >0 
 12      order by   p.rxcrcerror desc
 13  )
 14  select *
 15  from   p
 16  where rownum <=10
 17  ;

已解释。

SQL> select * from table(dbms_xplan.display);

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
Plan hash value: 733587010

----------------------------------------------------------------------------------------------------
| Id  | Operation                           | Name           | Rows  | Bytes | Cost (%CPU)| Time     | Pstart| Pstop |
----------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT                    |                |    10 |  3430 |  1125K (19)| 03:45:09 |       |       |
|*  1 |  COUNT STOPKEY                      |                |       |       |            |          |       |       |
|   2 |   VIEW                              |                |   133 | 45619 |  1125K (19)| 03:45:09 |       |       |
|*  3 |    SORT ORDER BY STOPKEY            |                |   133 | 22743 |  1125K (19)| 03:45:09 |       |       |
|*  4 |     FILTER                          |                |       |       |            |          |       |       |
|*  5 |      HASH JOIN                      |                |   133 | 22743 |  1125K (19)| 03:45:09 |       |       |
|*  6 |       HASH JOIN SEMI                |                |   133 | 19950 |  1125K (19)| 03:45:08 |       |       |
|*  7 |        HASH JOIN                    |                |   219 | 28251 |  1125K (19)| 03:45:08 |       |       |
|   8 |         NESTED LOOPS                |                |   219 | 25185 |  1125K (19)| 03:45:08 |       |       |
|   9 |          PARTITION RANGE ITERATOR   |                |   219 | 10074 |  1125K (19)| 03:45:03 |   KEY |   KEY |
|* 10 |           TABLE ACCESS FULL         | PERF_T_PONPORT |   219 | 10074 |  1125K (19)| 03:45:03 |   KEY |   KE
|  11 |          TABLE ACCESS BY INDEX ROWID| DEVICE         |     1 |    69 |     2   (0)| 00:00:01 |       |     
|* 12 |           INDEX UNIQUE SCAN         | PK_DEVICE      |     1 |       |     1   (0)| 00:00:01 |       |      
|  13 |         TABLE ACCESS FULL           | NODE           |  1214 | 16996 |     8   (0)| 00:00:01 |       |       |
|* 14 |        INDEX RANGE SCAN             | SYS_C00543203  |  1167 | 24507 |    10   (0)| 00:00:01 |       |
|  15 |       TABLE ACCESS FULL             | NODE           |  1214 | 25494 |     8   (0)| 00:00:01 |       |      
----------------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   1 - filter(ROWNUM<=10)
   3 - filter(ROWNUM<=10)
   4 - filter(TRUNC(SYSDATE@!-1,'fmdd')<=TRUNC(SYSDATE@!,'fmdd'))
   5 - access("C"."CITYNODECODE"="NP"."NODECODE")
   6 - access("C"."NODECODE"="S"."NODECODE")
   7 - access("D"."NODECODE"="C"."NODECODE")
  10 - filter("P"."RXCRCERROR" IS NOT NULL AND "P"."RXCRCERROR">0 AND
              "P"."COLTIME">=TRUNC(SYSDATE@!-1,'fmdd') AND "P"."COLTIME"<=TRUNC(SYSDATE@!,'fmdd'))
  12 - access("P"."RESID"="D"."DEVICEID" AND "D"."CHANGETYPE"=0)
  14 - access("S"."NETUSERID"='admin' AND "S"."AUTHTYPE"='VIEW')

已选择36行。

查看执行计划：id为4的filter过滤条件为filter(TRUNC(SYSDATE@!-1,'fmdd')<=TRUNC(SYSDATE@!,'fmdd'))。查看id为9的执行计划访问分区的方式为：PARTITION RANGE ITERATOR。说明分区表PERF_T_PONPORT的分区列的条件导致了性能压力。

coltime的列都是yyyy/mm/dd的格式，因此可以将PERF_T_PONPORT的分区列的条件条件改写为：(p.coltime =trunc(sysdate-1,'dd') or p.coltime =trunc(sysdate,'dd') )。

改写后的语句：

with p as(
     select  np.nodecode , np.nodename, d.deviceid, d.devicename, d.loopaddress, p.respara, p.rxcrcerror, p.txcrcerror
     from   perf_t_ponport p,device d, node c,node np
     where  p.resid = d.deviceid
     and    d.nodecode = c.nodecode 
     and    c.citynodecode = np.nodecode
     and    d.changetype = 0
     and  c.nodecode in (SELECT S.NODECODE FROM SINGLEUSERNODEAUTH S WHERE S.NETUSERID = 'admin' AND S.AUTHTYPE = 'VIEW')
     and    (p.coltime =trunc(sysdate-1,'dd') or p.coltime =trunc(sysdate,'dd') )
     and    p.rxcrcerror is not null
     and    p.rxcrcerror >0 
    order by   p.rxcrcerror desc
)
select *
from   p
where rownum <=10;

改写后的执行计划：

SQL> explain plan for with p as(
  2       select  np.nodecode , np.nodename, d.deviceid, d.devicename, d.loopaddress, p.respara, p.r
xcrcerror, p.txcrcerror
  3       from   perf_t_ponport p,device d, node c,node np
  4       where  p.resid = d.deviceid
  5       and    d.nodecode = c.nodecode 
  6       and    c.citynodecode = np.nodecode
  7       and    d.changetype = 0
  8       and  c.nodecode in (SELECT S.NODECODE FROM SINGLEUSERNODEAUTH S WHERE S.NETUSERID = 'admin
' AND S.AUTHTYPE = 'VIEW')
  9       and    (p.coltime =trunc(sysdate-1,'dd') or p.coltime =trunc(sysdate,'dd') )
 10       and    p.rxcrcerror is not null
 11       and    p.rxcrcerror >0 
 12      order by   p.rxcrcerror desc
 13  )
 14  select *
 15  from   p
 16  where rownum <=10;

已解释。

SQL> 
SQL> select * from table(dbms_xplan.display);

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
Plan hash value: 2287749996

----------------------------------------------------------------------------------------------------
| Id  | Operation                          | Name           | Rows  | Bytes | Cost (%CPU)| Time     | Pstart| Pstop |
----------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT                   |                |    10 |  3430 |   915   (2)| 00:00:11 |       |       |
|*  1 |  COUNT STOPKEY                     |                |       |       |            |          |       |       |
|   2 |   VIEW                             |                |   266 | 91238 |   915   (2)| 00:00:11 |       |       |
|*  3 |    SORT ORDER BY STOPKEY           |                |   266 | 45486 |   915   (2)| 00:00:11 |       |       |
|*  4 |     HASH JOIN                      |                |   266 | 45486 |   915   (2)| 00:00:11 |       |       |
|   5 |      TABLE ACCESS FULL             | NODE           |  1214 | 25494 |     8   (0)| 00:00:01 |       |       |
|*  6 |      HASH JOIN RIGHT SEMI          |                |   267 | 40050 |   905   (2)| 00:00:11 |       |       |
|*  7 |       INDEX RANGE SCAN             | SYS_C00543203  |  1167 | 24507 |    10   (0)| 00:00:01 |       |     
|*  8 |       HASH JOIN                    |                |   437 | 56373 |   895   (2)| 00:00:11 |       |       |
|   9 |        TABLE ACCESS FULL           | NODE           |  1214 | 16996 |     8   (0)| 00:00:01 |       |       |
|  10 |        NESTED LOOPS                |                |   437 | 50255 |   885   (2)| 00:00:11 |       |       |
|  11 |         PARTITION RANGE INLIST     |                |   437 | 20102 |     2   (0)| 00:00:01 |KEY(I) |KEY(I) |
|* 12 |          TABLE ACCESS FULL         | PERF_T_PONPORT |   437 | 20102 |     2   (0)| 00:00:01 |KEY(I) |KEY(I) 
|  13 |         TABLE ACCESS BY INDEX ROWID| DEVICE         |     1 |    69 |     2   (0)| 00:00:01 |       |       |
|* 14 |          INDEX UNIQUE SCAN         | PK_DEVICE      |     1 |       |     1   (0)| 00:00:01 |       |       |
----------------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   1 - filter(ROWNUM<=10)
   3 - filter(ROWNUM<=10)
   4 - access("C"."CITYNODECODE"="NP"."NODECODE")
   6 - access("C"."NODECODE"="S"."NODECODE")
   7 - access("S"."NETUSERID"='admin' AND "S"."AUTHTYPE"='VIEW')
   8 - access("D"."NODECODE"="C"."NODECODE")
  12 - filter("P"."RXCRCERROR" IS NOT NULL AND "P"."RXCRCERROR">0 AND
              ("P"."COLTIME"=TRUNC(SYSDATE@!-1,'fmdd') OR "P"."COLTIME"=TRUNC(SYSDATE@!,'fmdd')))
  14 - access("P"."RESID"="D"."DEVICEID" AND "D"."CHANGETYPE"=0)

已选择34行。

改写后， SQL执行花了9秒钟，性能提升了9倍。改写后的SQL消除了filter，访问分区的方式为 PARTITION RANGE INLIST 。

关于几种分区访问的方式：

范围分区：

1、PARTITION RANGE ITERATOR

SQL> explain plan for select * from  perf_t_ponport p where p.coltime <trunc(sysdate,'dd');

已解释。

SQL> select * from table(dbms_xplan.display);

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
Plan hash value: 4015217925

----------------------------------------------------------------------------------------------------
| Id  | Operation                | Name           | Rows  | Bytes | Cost (%CPU)| Time     | Pstart| Pstop |
----------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT         |                |   100 |  4600 |     2   (0)| 00:00:01 |       |       |
|   1 |  PARTITION RANGE ITERATOR|                |   100 |  4600 |     2   (0)| 00:00:01 |     1 |   KEY |
|*  2 |   TABLE ACCESS FULL      | PERF_T_PONPORT |   100 |  4600 |     2   (0)| 00:00:01 |     1 |   KEY |
----------------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   2 - filter("P"."COLTIME"<TRUNC(SYSDATE@!,'fmdd'))

已选择14行。

SQL> explain plan for select * from  perf_t_ponport p where p.coltime > trunc(sysdate-1,'dd') and p.
coltime <trunc(sysdate,'dd');

已解释。

SQL> select * from table(dbms_xplan.display);

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
Plan hash value: 1162550374

----------------------------------------------------------------------------------------------------
| Id  | Operation                 | Name           | Rows  | Bytes | Cost (%CPU)| Time     | Pstart| Pstop |
----------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT          |                |   100 |  4600 |  1637  (37)| 00:00:20 |       |       |
|*  1 |  FILTER                   |                |       |       |            |          |       |       |
|   2 |   PARTITION RANGE ITERATOR|                |   100 |  4600 |  1637  (37)| 00:00:20 |   KEY |   KEY |
|*  3 |    TABLE ACCESS FULL      | PERF_T_PONPORT |   100 |  4600 |  1637  (37)| 00:00:20 |   KEY |   
----------------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   1 - filter(TRUNC(SYSDATE@!-1,'fmdd')<TRUNC(SYSDATE@!,'fmdd'))
   3 - filter("P"."COLTIME">TRUNC(SYSDATE@!-1,'fmdd') AND "P"."COLTIME"<TRUNC(SYSDATE@!,'fmdd'))

已选择16行。

PARTITION RANGE ITERATOR是通过连续的分区迭代来获取数据。

2、PARTITION RANGE SINGLE

SQL> explain plan for select * from  perf_t_ponport partition(P_20170307) p;

已解释。

SQL> select * from table(dbms_xplan.display);

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
Plan hash value: 1021280532

----------------------------------------------------------------------------------------------------
| Id  | Operation              | Name           | Rows  | Bytes | Cost (%CPU)| Time     | Pstart| Pstop |
----------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT       |                |   100 |  4600 |     2   (0)| 00:00:01 |       |       |
|   1 |  PARTITION RANGE SINGLE|                |   100 |  4600 |     2   (0)| 00:00:01 |    85 |    85 |
|   2 |   TABLE ACCESS FULL    | PERF_T_PONPORT |   100 |  4600 |     2   (0)| 00:00:01 |    85 |   
----------------------------------------------------------------------------------------------------

已选择9行。

SQL> explain plan for select * from  perf_t_ponport p where p.coltime = trunc(sysdate-1,'dd') and p.
coltime <trunc(sysdate,'dd');

已解释。

SQL> select * from table(dbms_xplan.display);

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
Plan hash value: 506920385

----------------------------------------------------------------------------------------------------
| Id  | Operation               | Name           | Rows  | Bytes | Cost (%CPU)| Time     | Pstart| Pstop |
----------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT        |                |   100 |  4600 |     8  (25)| 00:00:01 |       |       |
|*  1 |  FILTER                 |                |       |       |            |          |       |       |
|   2 |   PARTITION RANGE SINGLE|                |   100 |  4600 |     8  (25)| 00:00:01 |   KEY |   KEY |
|*  3 |    TABLE ACCESS FULL    | PERF_T_PONPORT |   100 |  4600 |     8  (25)| 00:00:01 |   KEY |   KE
----------------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   1 - filter(TRUNC(SYSDATE@!-1,'fmdd')<TRUNC(SYSDATE@!,'fmdd'))
   3 - filter("P"."COLTIME"=TRUNC(SYSDATE@!-1,'fmdd') AND "P"."COLTIME"<TRUNC(SYSDATE@!,'fmdd'))

已选择16行。

PARTITION RANGE SINGLE只扫描一个分区。

3、PARTITION RANGE INLIST

SQL> explain plan for select * from  perf_t_ponport p where p.coltime = trunc(sysdate-1,'dd') or p.c
oltime = trunc(sysdate,'dd');

已解释。

SQL> select * from table(dbms_xplan.display);

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
Plan hash value: 2473962793

----------------------------------------------------------------------------------------------------
| Id  | Operation              | Name           | Rows  | Bytes | Cost (%CPU)| Time     | Pstart| Pstop |
----------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT       |                |   100 |  4600 |     2   (0)| 00:00:01 |       |       |
|   1 |  PARTITION RANGE INLIST|                |   100 |  4600 |     2   (0)| 00:00:01 |KEY(I) |KEY(I) |
|*  2 |   TABLE ACCESS FULL    | PERF_T_PONPORT |   100 |  4600 |     2   (0)| 00:00:01 |KEY(I) |KEY(I)
----------------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   2 - filter("P"."COLTIME"=TRUNC(SYSDATE@!-1,'fmdd') OR "P"."COLTIME"=TRUNC(SYSDATE@!,'fmdd'))

已选择14行。

上面的KEY(I)就是KEY(INLIST)的意思。PARTITION RANGE INLIST无法通过Pstart和Pstop看出分区的起始和结束位置。

4、PARTITION RANGE ALL和PARTITION RANGE OR

SQL> explain plan for select * from  perf_t_ponport p where p.coltime >trunc(sysdate-1,'dd') or  p.c
oltime < trunc(sysdate-5,'dd');

已解释。

SQL> select * from table(dbms_xplan.display);

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
Plan hash value: 3647984539

----------------------------------------------------------------------------------------------------
| Id  | Operation           | Name           | Rows  | Bytes | Cost (%CPU)| Time     | Pstart| Pstop |
----------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT    |                |   100 |  4600 |     2   (0)| 00:00:01 |       |       |
|   1 |  PARTITION RANGE ALL|                |   100 |  4600 |     2   (0)| 00:00:01 |     1 |   101 |
|*  2 |   TABLE ACCESS FULL | PERF_T_PONPORT |   100 |  4600 |     2   (0)| 00:00:01 |     1 |   101 |
----------------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   2 - filter("P"."COLTIME"<TRUNC(SYSDATE@!-5,'fmdd') OR
              "P"."COLTIME">TRUNC(SYSDATE@!-1,'fmdd'))

已选择15行。

ARTITION RANGE ALL是全分区扫描，上面是在oracle 10g环境测试，在Oracle 11g环境下，分区扫描方式为：PARTITION RANGE OR，可以看出11g对这种分区查询条件扫描方式做了优化。

SQL> explain plan for select * from  perf_t_ponport p where p.coltime >trunc(sysdate-1,'dd') or  p.c
oltime < trunc(sysdate-5,'dd');

已解释。

SQL> select * from table(dbms_xplan.display);

PLAN_TABLE_OUTPUT
----------------------------------------------------------------------------------------------------
Plan hash value: 470656424

----------------------------------------------------------------------------------------------------
| Id  | Operation          | Name           | Rows  | Bytes | Cost (%CPU)| Time     | Pstart| Pstop |
----------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT   |                |  1512M|    67G|  3783K  (3)| 12:36:37 |       |       |
|   1 |  PARTITION RANGE OR|                |  1512M|    67G|  3783K  (3)| 12:36:37 |KEY(OR)|KEY(OR)|
|*  2 |   TABLE ACCESS FULL| PERF_T_PONPORT |  1512M|    67G|  3783K  (3)| 12:36:37 |KEY(OR)|KEY(OR)|
----------------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   2 - filter("P"."COLTIME"<TRUNC(SYSDATE@!-5,'fmdd') OR
              "P"."COLTIME">TRUNC(SYSDATE@!-1,'fmdd'))

Note
-----
   - 'PLAN_TABLE' is old version

已选择19行。

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