Oracle 如何根据动态性能视图来查看某条SQL语句的执行计划

Oracle 如何根据动态性能视图来查看某条SQL语句的执行计划

1、授权某用户查看 sys.v$sql_plan 的权限

2、创建类plan_table的视图      

SQL> create or replace view dynamic_plan_table
  2  as
  3  select rawtohex(address)|| '_' ||child_number statement_id,
  4  sysdate timestamp,operation,options,object_node,
  5  object_owner,object_name,0 object_instance,
  6  optimizer,search_columns,id,parent_id,position,
  7  cost,cardinality,bytes,other_tag,partition_start,
  8  partition_stop,partition_id,other,distribution,
  9  cpu_cost,io_cost,temp_space,access_predicates,
 10  filter_predicates
 11  from v$sql_plan;

视图已创建。

3、查看执行计划

SQL> select plan_table_output
  2  from table(dbms_xplan.display
  3     ('dynamic_plan_table',
  4      (select rawtohex(address)||'_'||child_number x
  5         from v$sql where sql_text=
  6         'select * from user_tables'),
  7         'serial'))
  8  /

PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------

------------------------------------------------------------------------------
| Id  | Operation                    | Name     | Rows  | Bytes | Cost (%CPU)|
------------------------------------------------------------------------------
|   0 | SELECT STATEMENT             |          |       |       |   703 (100)|
|*  1 |  HASH JOIN                   |          |  2513 |  5700K|   703   (7)|
|   2 |   FIXED TABLE FULL           | X$KSPPCV |   100 |   196K|     0   (0)|
|   3 |   MERGE JOIN CARTESIAN       |          |  2513 |   755K|   703   (7)|
|*  4 |    HASH JOIN OUTER           |          |  2513 |   620K|   661   (1)|
|*  5 |     HASH JOIN RIGHT OUTER    |          |  2513 |   547K|   473   (2)|
|   6 |      TABLE ACCESS FULL       | USER$    |    84 |  1428 |     3   (0)|

PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
|*  7 |      HASH JOIN OUTER         |          |  2513 |   505K|   470   (2)|
|*  8 |       HASH JOIN              |          |  2513 |   485K|   415   (1)|
|   9 |        TABLE ACCESS FULL     | TS$      |     7 |   133 |     4   (0)|
|* 10 |        HASH JOIN OUTER       |          |  2513 |   439K|   410   (1)|
|  11 |         NESTED LOOPS         |          |  2485 |   325K|   352   (1)|
|* 12 |          TABLE ACCESS FULL   | OBJ$     |  3142 |   110K|   236   (2)|
|* 13 |          TABLE ACCESS CLUSTER| TAB$     |     1 |    98 |     1   (0)|
|* 14 |           INDEX UNIQUE SCAN  | I_OBJ#   |     1 |       |     0   (0)|
|  15 |         TABLE ACCESS FULL    | SEG$     |  7092 |   311K|    58   (0)|
|  16 |       INDEX FAST FULL SCAN   | I_OBJ1   | 69116 |   539K|    54   (0)|
|  17 |     INDEX FAST FULL SCAN     | I_OBJ2   | 69116 |  2024K|   187   (0)|

PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
|  18 |    BUFFER SORT               |          |     1 |    55 |   516  (10)|
|* 19 |     FIXED TABLE FULL         | X$KSPPI  |     1 |    55 |     0   (0)|
------------------------------------------------------------------------------

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

   1 - access("KSPPI"."INDX"="KSPPCV"."INDX")
   4 - access("T"."BOBJ#"="CO"."OBJ#")
   5 - access("CX"."OWNER#"="CU"."USER#")
   7 - access("T"."DATAOBJ#"="CX"."OBJ#")

PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
   8 - access("T"."TS#"="TS"."TS#")
  10 - access("T"."FILE#"="S"."FILE#" AND "T"."BLOCK#"="S"."BLOCK#" AND
              "T"."TS#"="S"."TS#")
  12 - filter(("O"."OWNER#"=USERENV('SCHEMAID') AND
              BITAND("O"."FLAGS",128)=0))
  13 - filter(BITAND("T"."PROPERTY",1)=0)
  14 - access("O"."OBJ#"="T"."OBJ#")
  19 - filter("KSPPI"."KSPPINM"='_dml_monitoring_enabled')

Note
-----

PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
   - 'DYNAMIC_PLAN_TABLE' is old version

已选择45行。

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