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 1.Ê×ÏÈÐèÒª½¨Á¢plan table,·ñÔò²»ÄÜʹÓÃ
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utlxplan.sql
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create table PLAN_TABLE (
 statement_id  varchar2(30),
 timestamp     date,
 remarks       varchar2(80),
 operation     varchar2(30),
 options        varchar2(255),
 object_node   varchar2(128),
 object_owner  varchar2(30),
 object_name   varchar2(30),
 object_instance numeric,
 object_type     varchar2(30),
 optimizer       varchar2(255),
 search_columns  number,
 id  numeric,
 parent_id numeric,
 position numeric,
 cost  numeric,
 cardinality numeric,
 bytes  numeric,
 other_tag       varchar2(255),
 partition_start varchar2(255),
        partition_stop  varchar2(255),
        partition_id    numeric,
 other  long,
 distribution    varchar2(30),
 cpu_cost numeric,
 io_cost  numeric,
 temp_space numeric,
        access_predicates varchar2(4000),
        filter_predicates varchar2(4000));
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SQL>$ORACLE/rdbms/admin/utlxplan.sql
2.ʹÓÃexplain plan forÓï¾ä½øÐÐÖ´Ðмƻ®·ÖÎö
SQL> explain plan for
  2  select * from dual;
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3.¿ÉÒԲ鿴ִÐмƻ®ÁË
select * from table(DBMS_XPLAN.display);
--------------------------------------------------------------------
| Id  | Operation            |  Name    


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