分页语句的深入研究

select *
  from (select   
                         a.cert_type,
               a.cert_no,
               a.cust_name,
               e.oper_no,
               to_char(c.vou_start_no + instr(c.vou_status, '0') - 1,
                       'fm00000000') as vou,
               e.bran_code
          from comr_cifbinfo   a,
               comc_box        b,
               comr_clerk_vou  c,
               auto_comc_clerk e
         where a.cert_type = '1'
           and substr(rtrim(a.cert_no), 18, 1) is not null
           and a.cert_no not in
               ('330721197211217006X', '1302011981101070315')
           and a.valid_flag = '0'
           and not exists
         (select  * from comr_cifacctno ta where ta.cust_no = a.cust_no)
           and c.vou_status like '%0%'
           and b.bran_code = e.bran_code
           and c.bran_code = e.bran_code
           and a.bank_corp_code = c.bank_corp_code
           and b.box_no = c.box_no
           and b.oper_no = e.oper_no
           and c.vou_status like '%0%'
           and c.vou_type = '11'
           and c.sub_vou_type = '0'
           and e.post_no in ('12002', '12402')
           and e.flag = '0'
         order by vou asc)
 where rownum < 2;


之前的SQL 由于有坑爹的c.vou_status like '%0%' 条件,导致最终分页SQL无法彻底优化，这次先把like搞掉


SQL> select * from table(dbms_xplan.display_cursor(null,null,'ALLSTATS LAST'));


PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
SQL_ID  gv9chqfu3770y, child number 0
-------------------------------------
select *   from (select                          a.cert_type,
     a.cert_no,                a.cust_name,                e.oper_no,
             to_char(c.vou_start_no + instr(c.vou_status, '0') - 1,
                   'fm00000000') as vou,                e.bran_code
      from comr_cifbinfo   a,                comc_box        b,
       comr_clerk_vou  c,                auto_comc_clerk e
where a.cert_type = '1'            and substr(rtrim(a.cert_no), 18, 1)
is not null            and a.cert_no not in
('330721197211217006X', '1302011981101070315')            and
a.valid_flag = '0'            and not exists          (select  * from
comr_cifacctno ta where ta.cust_no = a.cust_no)         /*   and
c.vou_status like '%0%'*/            and b.bran_code = e.bran_code
      and c.bran_code = e.bran_code            and a.bank_corp_code =
c.bank_corp_code            and b.box_no = c.box_no            and
b.oper_no = e.oper_no          /*  a

Plan hash value: 2236318696

-------------------------------------------------------------------------------------------------------------------
| Id  | Operation                         | Name                | Starts | E-Rows | A-Rows |   A-Time   | Buffers |
-------------------------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT                  |                     |      1 |        |      1 |00:00:00.28 |   12288 |
|*  1 |  COUNT STOPKEY                    |                     |      1 |        |      1 |00:00:00.28 |   12288 |
|   2 |   VIEW                            |                     |      1 |      1 |      1 |00:00:00.28 |   12288 |
|   3 |    NESTED LOOPS ANTI              |                     |      1 |      1 |      1 |00:00:00.28 |   12288 |
|   4 |     NESTED LOOPS                  |                     |      1 |    103 |   3843 |00:00:00.26 |    7317 |
|   5 |      NESTED LOOPS                 |                     |      1 |      1 |      1 |00:00:00.01 |     406 |
|   6 |       NESTED LOOPS                |                     |      1 |    179 |    198 |00:00:00.01 |      89 |
|   7 |        TABLE ACCESS BY INDEX ROWID| COMR_CLERK_VOU      |      1 |   2487 |      6 |00:00:00.01 |       9 |
|*  8 |         INDEX RANGE SCAN          | IDX_COMR_CLERK_VOU  |      1 |     15 |      6 |00:00:00.01 |       3 |
|*  9 |        TABLE ACCESS FULL          | COMC_BOX            |      6 |     12 |    198 |00:00:00.01 |      80 |
|* 10 |       TABLE ACCESS BY INDEX ROWID | AUTO_COMC_CLERK     |    198 |      1 |      1 |00:00:00.01 |     317 |
|* 11 |        INDEX UNIQUE SCAN          | AUTO_COMC_CLERK_INX |    198 |      1 |    162 |00:00:00.01 |     202 |
|* 12 |      TABLE ACCESS BY INDEX ROWID  | COMR_CIFBINFO       |      1 |    100 |   3843 |00:00:00.26 |    6911 |
|* 13 |       INDEX RANGE SCAN            | CIFB_IDX2           |      1 |    101 |   3843 |00:00:00.25 |    3138 |
|* 14 |     INDEX RANGE SCAN              | CIFACCTNO_IDX2      |   3843 |   2110K|   3842 |00:00:00.01 |    4971 |
-------------------------------------------------------------------------------------------------------------------

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

   1 - filter(ROWNUM<2)
   8 - access("C"."VOU_TYPE"=11 AND "C"."SUB_VOU_TYPE"=0)
   9 - filter("B"."BOX_NO"="C"."BOX_NO")
  10 - filter((INTERNAL_FUNCTION("E"."POST_NO") AND "E"."FLAG"='0' AND "B"."BRAN_CODE"="E"."BRAN_CODE" AND
              "C"."BRAN_CODE"="E"."BRAN_CODE"))
  11 - access("B"."OPER_NO"="E"."OPER_NO")
  12 - filter("A"."VALID_FLAG"='0')
  13 - access("A"."CERT_TYPE"='1' AND "A"."BANK_CORP_CODE"="C"."BANK_CORP_CODE")
       filter((SUBSTR(RTRIM("A"."CERT_NO"),18,1) IS NOT NULL AND "A"."CERT_NO"<>'330721197211217006X' AND
              "A"."CERT_NO"<>'1302011981101070315' AND "A"."BANK_CORP_CODE"="C"."BANK_CORP_CODE"))
  14 - access("TA"."CUST_NO"="A"."CUST_NO")


55 rows selected.

create index IDX_COMR_CLERK_VOU on COMR_CLERK_VOU (VOU_TYPE, SUB_VOU_TYPE, TO_CHAR(VOU_START_NO+INSTR(VOU_STATUS,'0')-1,'fm00000000'))


|*  8 |         INDEX RANGE SCAN          | IDX_COMR_CLERK_VOU  |      1 |     15 |      6 |00:00:00.01 |       3 |


此时扫描了6条记录停止