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SQL执行异常系列之——隐式转换

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标签:pre   exec   statistic   drop   row   orm   fun   obj   ips   

SQL> select object_id,CREATED from dba_objects where rownum < 10;

 OBJECT_ID CREATED
---------- ------------------
    20 25-JUL-18
    46 25-JUL-18
    28 25-JUL-18
    15 25-JUL-18
    29 25-JUL-18
     3 25-JUL-18
    25 25-JUL-18
    41 25-JUL-18
    54 25-JUL-18

9 rows selected.




select object_name from function where  to_char(created,‘yyyymmdd hh24:mi‘)=‘20180725 12:51‘;

20180725 12:54





drop table tab;
create table tab(id number(20),datetime date);



declare
i number;
dd date;
BEGIN
dd := sysdate;
i:= 0;
for x in 1..5000 loop 
--if mod(i,100)=0 then
insert into tab(id,datetime) values(i,dd);
dd := dd+1; 
i := i+1;
end loop;
END;
/


create table tab(id varchar2(20),datetime date);



1289             20220429 13:58


29-APR-22


************************
测试1
************************

select * from tab where id=1289 and datetime=‘29-APR-22‘;


select * from tab where id=1289 and datetime=‘29-APR-22‘;SQL> 

no rows selected


Execution Plan
----------------------------------------------------------
Plan hash value: 1995730731

--------------------------------------------------------------------------
| Id  | Operation      | Name | Rows  | Bytes | Cost (%CPU)| Time     |
--------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |     |     1 |    21 |     5   (0)| 00:00:01 |
|*  1 |  TABLE ACCESS FULL| TAB  |     1 |    21 |     5   (0)| 00:00:01 |
--------------------------------------------------------------------------

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

   1 - filter(TO_NUMBER("ID")=1289 AND "DATETIME"=‘29-APR-22‘)

Note
-----
   - dynamic sampling used for this statement (level=2)


Statistics
----------------------------------------------------------
      5  recursive calls
      0  db block gets
     33  consistent gets
      0  physical reads
      0  redo size
    400  bytes sent via SQL*Net to client
    508  bytes received via SQL*Net from client
      1  SQL*Net roundtrips to/from client
      0  sorts (memory)
      0  sorts (disk)
      0  rows processed


************************
测试2
************************

select * from tab where id=‘1289‘ and datetime=‘29-APR-22‘;
select * from tab where id=‘1289‘ and datetime=‘29-APR-22‘;


SQL> 

no rows selected


Execution Plan
----------------------------------------------------------
Plan hash value: 1995730731

--------------------------------------------------------------------------
| Id  | Operation      | Name | Rows  | Bytes | Cost (%CPU)| Time     |
--------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |     |     1 |    21 |     5   (0)| 00:00:01 |
|*  1 |  TABLE ACCESS FULL| TAB  |     1 |    21 |     5   (0)| 00:00:01 |
--------------------------------------------------------------------------

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

   1 - filter("ID"=‘1289‘ AND "DATETIME"=‘29-APR-22‘)

Note
-----
   - dynamic sampling used for this statement (level=2)


Statistics
----------------------------------------------------------
      5  recursive calls
      0  db block gets
     33  consistent gets
      0  physical reads
      0  redo size
    400  bytes sent via SQL*Net to client
    508  bytes received via SQL*Net from client
      1  SQL*Net roundtrips to/from client
      0  sorts (memory)
      0  sorts (disk)
      0  rows processed



刷新cache之后再执行

SQL> select * from tab where id=‘1289‘ and datetime=‘29-APR-22‘;

no rows selected


Execution Plan
----------------------------------------------------------
Plan hash value: 1995730731

--------------------------------------------------------------------------
| Id  | Operation      | Name | Rows  | Bytes | Cost (%CPU)| Time     |
--------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |     |     1 |    21 |     5   (0)| 00:00:01 |
|*  1 |  TABLE ACCESS FULL| TAB  |     1 |    21 |     5   (0)| 00:00:01 |
--------------------------------------------------------------------------

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

   1 - filter("ID"=‘1289‘ AND "DATETIME"=‘29-APR-22‘)

Note
-----
   - dynamic sampling used for this statement (level=2)


Statistics
----------------------------------------------------------
      0  recursive calls
      0  db block gets
     16  consistent gets
     14  physical reads
      0  redo size
    400  bytes sent via SQL*Net to client
    508  bytes received via SQL*Net from client
      1  SQL*Net roundtrips to/from client
      0  sorts (memory)
      0  sorts (disk)
      0  rows processed



************************
测试3
************************
select * from tab where id=‘1289‘ and to_char(datetime,‘yyyymmdd‘)=‘20220429‘;
SQL> select * from tab where id=‘1289‘ and to_char(datetime,‘yyyymmdd‘)=‘20220429‘;

ID             DATETIME
-------------------- --------------
1289             29-04-22 13:58


Execution Plan
----------------------------------------------------------
Plan hash value: 1995730731

--------------------------------------------------------------------------
| Id  | Operation      | Name | Rows  | Bytes | Cost (%CPU)| Time     |
--------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |     |     1 |    13 |     5   (0)| 00:00:01 |
|*  1 |  TABLE ACCESS FULL| TAB  |     1 |    13 |     5   (0)| 00:00:01 |
--------------------------------------------------------------------------

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

   1 - filter("ID"=‘1289‘ AND TO_CHAR(INTERNAL_FUNCTION("DATETIME"),‘yyy
          ymmdd‘)=‘20220429‘)


Statistics
----------------------------------------------------------
     62  recursive calls
      0  db block gets
     51  consistent gets
      0  physical reads
      0  redo size
    600  bytes sent via SQL*Net to client
    519  bytes received via SQL*Net from client
      2  SQL*Net roundtrips to/from client
      4  sorts (memory)
      0  sorts (disk)
      1  rows processed




************************
测试4
************************
create index tab_index on tab(id,to_char(datetime,‘yyyymmdd‘));

SQL> /

ID             DATETIME
-------------------- --------------
1289             29-04-22 13:58


Execution Plan
----------------------------------------------------------
Plan hash value: 4028735706

-----------------------------------------------------------------------------------------
| Id  | Operation            | Name    | Rows    | Bytes | Cost (%CPU)| Time    |
-----------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT        |        |     1 |    13 |     2   (0)| 00:00:01 |
|   1 |  TABLE ACCESS BY INDEX ROWID| TAB    |     1 |    13 |     2   (0)| 00:00:01 |
|*  2 |   INDEX RANGE SCAN        | TAB_INDEX |     1 |    |     1   (0)| 00:00:01 |
-----------------------------------------------------------------------------------------

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

   2 - access("ID"=‘1289‘ AND TO_CHAR(INTERNAL_FUNCTION("DATETIME"),‘yyyymmdd‘)=‘
          20220429‘)


Statistics
----------------------------------------------------------
      0  recursive calls
      0  db block gets
      4  consistent gets
      3  physical reads
      0  redo size
    600  bytes sent via SQL*Net to client
    519  bytes received via SQL*Net from client
      2  SQL*Net roundtrips to/from client
      0  sorts (memory)
      0  sorts (disk)
      1  rows processed



************************
测试5
************************

新创建的表
select * from tab where id=‘1289‘ and to_char(datetime,‘yyyymmdd‘)=‘20220429‘;
SQL> /

    ID DATETIME
---------- --------------
      1289 29-04-22 22:42


Execution Plan
----------------------------------------------------------
Plan hash value: 1995730731

--------------------------------------------------------------------------
| Id  | Operation      | Name | Rows  | Bytes | Cost (%CPU)| Time     |
--------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |     |     1 |    22 |     5   (0)| 00:00:01 |
|*  1 |  TABLE ACCESS FULL| TAB  |     1 |    22 |     5   (0)| 00:00:01 |
--------------------------------------------------------------------------

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

   1 - filter("ID"=1289 AND TO_CHAR(INTERNAL_FUNCTION("DATETIME"),‘yyyym
          mdd‘)=‘20220429‘)

Note
-----
   - dynamic sampling used for this statement (level=2)


Statistics
----------------------------------------------------------
      0  recursive calls
      0  db block gets
     17  consistent gets
     14  physical reads
      0  redo size
    599  bytes sent via SQL*Net to client
    519  bytes received via SQL*Net from client
      2  SQL*Net roundtrips to/from client
      0  sorts (memory)
      0  sorts (disk)
      1  rows processed


************************
测试5
************************

create index tab_index on tab(id,to_char(datetime,‘yyyymmdd‘));

SQL> select * from tab where id=‘1289‘ and to_char(datetime,‘yyyymmdd‘)=‘20220429‘;

    ID DATETIME
---------- --------------
      1289 29-04-22 22:42


Execution Plan
----------------------------------------------------------
Plan hash value: 4028735706

-----------------------------------------------------------------------------------------
| Id  | Operation            | Name    | Rows    | Bytes | Cost (%CPU)| Time    |
-----------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT        |        |     1 |    28 |     2   (0)| 00:00:01 |
|   1 |  TABLE ACCESS BY INDEX ROWID| TAB    |     1 |    28 |     2   (0)| 00:00:01 |
|*  2 |   INDEX RANGE SCAN        | TAB_INDEX |     1 |    |     1   (0)| 00:00:01 |
-----------------------------------------------------------------------------------------

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

   2 - access("ID"=1289 AND TO_CHAR(INTERNAL_FUNCTION("DATETIME"),‘yyyymmdd‘)=‘20
          220429‘)

Note
-----
   - dynamic sampling used for this statement (level=2)


Statistics
----------------------------------------------------------
     10  recursive calls
      0  db block gets
     27  consistent gets
      3  physical reads
      0  redo size
    599  bytes sent via SQL*Net to client
    519  bytes received via SQL*Net from client
      2  SQL*Net roundtrips to/from client
      0  sorts (memory)
      0  sorts (disk)
      1  rows processed





************************
测试6
************************
select * from tab where id=1289 and to_char(datetime,‘yyyymmdd‘)=‘20220429‘;


SQL> select * from tab where id=1289 and to_char(datetime,‘yyyymmdd‘)=‘20220429‘;

    ID DATETIME
---------- --------------
      1289 29-04-22 22:42


Execution Plan
----------------------------------------------------------
Plan hash value: 4028735706

-----------------------------------------------------------------------------------------
| Id  | Operation            | Name    | Rows    | Bytes | Cost (%CPU)| Time    |
-----------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT        |        |     1 |    28 |     2   (0)| 00:00:01 |
|   1 |  TABLE ACCESS BY INDEX ROWID| TAB    |     1 |    28 |     2   (0)| 00:00:01 |
|*  2 |   INDEX RANGE SCAN        | TAB_INDEX |     1 |    |     1   (0)| 00:00:01 |
-----------------------------------------------------------------------------------------

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

   2 - access("ID"=1289 AND TO_CHAR(INTERNAL_FUNCTION("DATETIME"),‘yyyymmdd‘)=‘20
          220429‘)

Note
-----
   - dynamic sampling used for this statement (level=2)


Statistics
----------------------------------------------------------
      7  recursive calls
      0  db block gets
     25  consistent gets
      0  physical reads
      0  redo size
    599  bytes sent via SQL*Net to client
    519  bytes received via SQL*Net from client
      2  SQL*Net roundtrips to/from client
      0  sorts (memory)
      0  sorts (disk)
      1  rows processed

************************
测试6
************************
select * from tab where to_char(id)=‘1289‘ and to_char(datetime,‘yyyymmdd‘)=‘20220429‘;
SQL> select * from tab where to_char(id)=‘1289‘ and to_char(datetime,‘yyyymmdd‘)=‘20220429‘;

    ID DATETIME
---------- --------------
      1289 29-04-22 22:42


Execution Plan
----------------------------------------------------------
Plan hash value: 1995730731

--------------------------------------------------------------------------
| Id  | Operation      | Name | Rows  | Bytes | Cost (%CPU)| Time     |
--------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |     |     1 |    28 |     5   (0)| 00:00:01 |
|*  1 |  TABLE ACCESS FULL| TAB  |     1 |    28 |     5   (0)| 00:00:01 |
--------------------------------------------------------------------------

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

   1 - filter(TO_CHAR("ID")=‘1289‘ AND
          TO_CHAR(INTERNAL_FUNCTION("DATETIME"),‘yyyymmdd‘)=‘20220429‘)

Note
-----
   - dynamic sampling used for this statement (level=2)


Statistics
----------------------------------------------------------
      5  recursive calls
      0  db block gets
     35  consistent gets
      0  physical reads
      0  redo size
    599  bytes sent via SQL*Net to client
    519  bytes received via SQL*Net from client
      2  SQL*Net roundtrips to/from client
      0  sorts (memory)
      0  sorts (disk)
      1  rows processed

 

SQL执行异常系列之——隐式转换

标签:pre   exec   statistic   drop   row   orm   fun   obj   ips   

原文地址:https://www.cnblogs.com/dayu-liu/p/9813797.html

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