数据库单条sql优化

数据库单条sql优化  （            gbk9rh97z5jca            ）

1.用pl/sql工具执行如下语句   （system用户）

DECLARE
  V_COUNT       NUMBER;
  V_TASK_NAME   VARCHAR2(30) := 'TUNING_FOR_SQL14';
  V_SQLSET_NAME VARCHAR2(30) := 'SQL_SET14';
  V_CURSOR      DBMS_SQLTUNE.SQLSET_CURSOR;
BEGIN

  SELECT COUNT(1)
    INTO V_COUNT
    FROM DBA_ADVISOR_LOG A
   WHERE A.TASK_NAME = V_TASK_NAME;
  IF V_COUNT <> 0 THEN
    DBMS_SQLTUNE.DROP_TUNING_TASK(TASK_NAME => V_TASK_NAME);
  END IF;

  SELECT COUNT(1)
    INTO V_COUNT
    FROM DBA_SQLSET A
   WHERE A.NAME = V_SQLSET_NAME;
  IF V_COUNT <> 0 THEN
    DBMS_SQLTUNE.DROP_SQLSET(SQLSET_NAME => V_SQLSET_NAME);
  END IF;

  DBMS_SQLTUNE.CREATE_SQLSET(SQLSET_NAME => V_SQLSET_NAME,
                             DESCRIPTION => 'FROM USER,FROM SNAP');
  OPEN V_CURSOR FOR
    SELECT *
      FROM (SELECT VALUE(P)
              FROM TABLE(DBMS_SQLTUNE.SELECT_WORKLOAD_REPOSITORY(BEGIN_SNAP => 45795,
                                                                 END_SNAP   => 45796)) P
             WHERE P.SQL_ID = 'gbk9rh97z5jca'
             ORDER BY CPU_TIME DESC) ;
  DBMS_SQLTUNE.LOAD_SQLSET(SQLSET_NAME     => V_SQLSET_NAME,
                           POPULATE_CURSOR => V_CURSOR);
  V_TASK_NAME := DBMS_SQLTUNE.CREATE_TUNING_TASK(TASK_NAME   => V_TASK_NAME,
                                                 SQLSET_NAME => V_SQLSET_NAME,
                                                 RANK1       => 'CPU_TIME',
                                                 TIME_LIMIT  => 300,
                                                 DESCRIPTION => 'TUNE SQLSET ORDERED BY CPU_TIME');
  
  DBMS_SQLTUNE.EXECUTE_TUNING_TASK(V_TASK_NAME);
END;
/

2.待上面执行完成后执行如下内容获取调优建议
--获取调优建议
SELECT DBMS_SQLTUNE.REPORT_TUNING_TASK('TUNING_FOR_SQL14') FROM DUAL;
--调优建议脚本
SELECT DBMS_SQLTUNE.SCRIPT_TUNING_TASK('TUNING_FOR_SQL14') FROM DUAL;

-v1