SQL语句优化

(一)语句一

SELECT *

FROM (SELECT DISTINCT A.DEALER_ID,

A.CO_NO,

A.RU_UPLOADED_DATE,

A.CLAIM_CATEGORY,

A.CO_STATUS,

A.INQUIRY_RESULT,

C.VIN,

C.PLATE_NO,

C.OWNER_NAME,

C.COMING_TIME,

D.DEALER_SHORT_NAME AS DEALER_NAME,

D.DEALER_CODE,

D.SV_CENTER_ID,

D.PROVINCE,

T3.OPINIONS_DLR,

T3.HANDLED_DATE_DLR,

T3.HANDLER_DLR,

A.CLAIMING_TYPE,

A.CI_HANDLE_RESULT

FROM TMP1 A

JOIN NT_AS_SERVICE_ORDERS C ON A.DEALER_ID = C.DEALER_ID

AND A.SO_NO = C.SO_NO

JOIN NT_BB_SERVICE_STATIONS D ON A.DEALER_ID = D.DEALER_ID

LEFT JOIN (SELECT DEALER_ID,

CO_NO,

INQUIRED_DATE,

OPINIONS_DLR,

HANDLED_DATE_DLR,

HANDLER_DLR,

ROW_NUMBER() OVER(PARTITION BY DEALER_ID, CO_NO ORDER BY

INQUIRED_DATE DESC) AS VALUE1

FROM NT_CI_CLAIMING_INQUIRIES) T3 ON A.DEALER_ID =

T3.DEALER_ID

AND A.CO_NO =

T3.CO_NO

AND T3.VALUE1 = 1

WHERE (A.COMPANY_ID = 1002 OR A.COMPANY_ID = 0)

AND A.IS_INACTIVE = 0

AND A.RU_UPLOADED_DATE >= to_date('2013-07-01','yyyy-mm-dd')

AND A.RU_UPLOADED_DATE <= to_date('2013-10-17','yyyy-mm-dd')

ORDER BY C.COMING_TIME, C.VIN DESC)

WHERE ROWNUM <= 5000

(二)执行计划

explain plan for SELECT *

FROM (SELECT DISTINCT A.DEALER_ID,

A.CO_NO,

A.RU_UPLOADED_DATE,

A.CLAIM_CATEGORY,

A.CO_STATUS,

A.INQUIRY_RESULT,

C.VIN,

C.PLATE_NO,

C.OWNER_NAME,

C.COMING_TIME,

D.DEALER_SHORT_NAME AS DEALER_NAME,

D.DEALER_CODE,

D.SV_CENTER_ID,

D.PROVINCE,

T3.OPINIONS_DLR,

T3.HANDLED_DATE_DLR,

T3.HANDLER_DLR,

A.CLAIMING_TYPE,

A.CI_HANDLE_RESULT

FROM TMP1 A

JOIN NT_AS_SERVICE_ORDERS C ON A.DEALER_ID = C.DEALER_ID

AND A.SO_NO = C.SO_NO

JOIN NT_BB_SERVICE_STATIONS D ON A.DEALER_ID = D.DEALER_ID

LEFT JOIN (SELECT DEALER_ID,

CO_NO,

INQUIRED_DATE,

OPINIONS_DLR,

HANDLED_DATE_DLR,

HANDLER_DLR,

ROW_NUMBER() OVER(PARTITION BY DEALER_ID, CO_NO ORDER BY

INQUIRED_DATE DESC) AS VALUE1

FROM NT_CI_CLAIMING_INQUIRIES) T3 ON A.DEALER_ID =

T3.DEALER_ID

AND A.CO_NO =

T3.CO_NO

AND T3.VALUE1 = 1

WHERE (A.COMPANY_ID = 1002 OR A.COMPANY_ID = 0)

AND A.IS_INACTIVE = 0

AND A.RU_UPLOADED_DATE >= to_date('2013-07-01','yyyy-mm-dd')

AND A.RU_UPLOADED_DATE <= to_date('2013-10-17','yyyy-mm-dd')

ORDER BY C.COMING_TIME, C.VIN DESC)

WHERE ROWNUM <= 5000

(三）查看执行计划

select * from table(dbms_xplan.display); #必须要在同一会话中执行

Plan hash value: 2332382148

-----------------------------------------------------------------------------------------------------------------------------------

| Id | Operation | Name | Rows | Bytes |TempSpc| Cost (%CPU)| Time | Pstart| Pstop |

-----------------------------------------------------------------------------------------------------------------------------------

| 0 | SELECT STATEMENT | | 5000 | 11M| | 211K (1)| 00:49:26 | | |

|* 1 | COUNT STOPKEY | | | | | | | | |

| 2 | VIEW | | 313K| 703M| | 211K (1)| 00:49:26 | | |

|* 3 | SORT UNIQUE STOPKEY | | 313K| 73M| 79M| 201K (1)| 00:47:00 | | |

|* 4 | HASH JOIN | | 313K| 73M| | 190K (1)| 00:44:34 | | |

| 5 | TABLE ACCESS FULL | NT_BB_SERVICE_STATIONS | 1690 | 55770 | | 73 (0)| 00:00:02 | | |

|* 6 | HASH JOIN OUTER | | 313K| 63M| 42M| 190K (1)| 00:44:33 | | |

|* 7 | HASH JOIN | | 250K| 39M| 25M| 177K (1)| 00:41:27 | | |

| 8 | PARTITION RANGE ITERATOR| | 250K| 22M| | 2427 (1)| 00:00:34 | 8 | 9 |

|* 9 | TABLE ACCESS FULL | TMP1 | 250K| 22M| | 2427 (1)| 00:00:34 | 8 | 9 |

| 10 | TABLE ACCESS FULL | NT_AS_SERVICE_ORDERS | 11M| 757M| | 136K (1)| 00:31:47 | | |

|* 11 | VIEW | | 921K| 41M| | 9264 (1)| 00:02:10 | | |

|* 12 | WINDOW SORT PUSHED RANK | | 921K| 39M| 56M| 9264 (1)| 00:02:10 | | |

| 13 | TABLE ACCESS FULL | NT_CI_CLAIMING_INQUIRIES | 921K| 39M| | 2690 (2)| 00:00:38 | | |

-----------------------------------------------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):

---------------------------------------------------

1 - filter(ROWNUM<=5000)

3 - filter(ROWNUM<=5000)

4 - access("A"."DEALER_ID"="D"."DEALER_ID")

6 - access("A"."CO_NO"="T3"."CO_NO"(+) AND "A"."DEALER_ID"="T3"."DEALER_ID"(+))

7 - access("A"."DEALER_ID"="C"."DEALER_ID" AND "A"."SO_NO"="C"."SO_NO")

9 - filter("A"."RU_UPLOADED_DATE"<=TIMESTAMP' 2013-10-17 00:00:00' AND "A"."IS_INACTIVE"=0 AND ("A"."COMPANY_ID"=0 OR

"A"."COMPANY_ID"=1002))

11 - filter("T3"."VALUE1"(+)=1)

12 - filter(ROW_NUMBER() OVER ( PARTITION BY "DEALER_ID","CO_NO" ORDER BY INTERNAL_FUNCTION("INQUIRED_DATE") DESC )<=1)

(4)解决方案

上面经过对tmp1的分区，降低很多的逻辑读现象，性能已经得到了很好的提升，但TMP1 通过外键与表NT_AS_SERVICE_ORDERS进行连接，

NT_AS_SERVICE_ORDERS C ON A.DEALER_ID = C.DEALER_ID

AND A.SO_NO = C.SO_NO

这样导致NT_AS_SERVICE_ORDERS 都是全表扫描，这里需要通过一个过滤条件，时间进行一个限制，这样也能解决表NT_AS_SERVICE_ORDERS 性能问题。COMING_TIME

alter table NT_AS_SERVICE_ORDERS

add constraint PK_NT_AS_SERVICE_ORDERS primary key (SO_NO, DEALER_ID)

using index

tablespace DCS

pctfree 10

initrans 2

maxtrans 255

storage

(

initial 80K

next 1M

minextents 1

maxextents unlimited

);