SET SERVEROUTPUT ON

SPOOL ALERT.LOG

DECLARE

   V_PERCENT    NUMBER := .05;

   V_BDUMP      VARCHAR2 (1000);

   V_NAME       VARCHAR2 (20);

   V_FILE       VARCHAR2 (20);

   V_LINE       VARCHAR2 (8000);

   V_HANDLE     UTL_FILE.FILE_TYPE;

   V_DIR_STMT   VARCHAR2 (100);

   V_SIZE       INTEGER;

   V_BSIZE      INTEGER;

   V_EXISTS     BOOLEAN;

BEGIN

   SELECT VALUE

     INTO V_BDUMP

     FROM V$PARAMETER

    WHERE NAME = 'background_dump_dest';

   DBMS_OUTPUT.PUT_LINE (

      '**************************** INFO *************************');

   DBMS_OUTPUT.PUT_LINE ('BDUMP: ' || V_BDUMP);

   SELECT VALUE

     INTO V_NAME

     FROM V$PARAMETER

    WHERE NAME = 'instance_name';

   DBMS_OUTPUT.PUT_LINE ('DB NAME: ' || V_NAME);

   V_FILE := 'alert_' || V_NAME || '.log';

   DBMS_OUTPUT.PUT_LINE ('FILENAME: ' || V_FILE);

   V_DIR_STMT := 'CREATE DIRECTORY ALERT AS ''' || V_BDUMP || '''';

   DBMS_OUTPUT.PUT_LINE ('COMMAND: ' || V_DIR_STMT);

   EXECUTE IMMEDIATE V_DIR_STMT;

   V_HANDLE := UTL_FILE.FOPEN ('ALERT', V_FILE, 'r');

   UTL_FILE.FGETATTR ('ALERT',

                      V_FILE,

                      V_EXISTS,

                      V_SIZE,

                      V_BSIZE);

   DBMS_OUTPUT.PUT_LINE ('ALERT SIZE: ' || V_SIZE / 1024 / 1024 || ' MB');

   UTL_FILE.FSEEK (V_HANDLE, NULL, V_SIZE * (1 - V_PERCENT));

   DBMS_OUTPUT.PUT_LINE (

      'FETCHED ALERT SIZE: ' || V_SIZE * (V_PERCENT / 1024 / 1024) || ' MB');

   DBMS_OUTPUT.PUT_LINE (

      '********************************************************');

   LOOP

      BEGIN

         UTL_FILE.GET_LINE (V_HANDLE, V_LINE);

         DBMS_OUTPUT.PUT_LINE (V_LINE);

      EXCEPTION

         WHEN NO_DATA_FOUND

         THEN

            EXIT;

      END;

   END LOOP;

   UTL_FILE.FCLOSE (V_HANDLE);

   EXECUTE IMMEDIATE 'DROP DIRECTORY ALERT';

END;

/

SPOOL OFF;

SELECT ORIGINATING_TIMESTAMP,

         MODULE_ID,

         PROCESS_ID,

         MESSAGE_TEXT

    FROM X$DBGALERTEXT

ORDER BY ORIGINATING_TIMESTAMP DESC;

  구분

 Sarnoff's Law 

 Metcalfe's Law 

 Reed's Law 

 가치

(n = 노드수) 

 N (선형적) 

 N^2 (비선형적) 

 2^n (기하급수적)

 참여자

 시청자 

 노드 

 노드간의 그룹

 의미

 네트워크 가치는 시청자의 수에 비례 

 네트워크 가치는 노드의 제곱에 비례 

 네트워크 가치는 노드 수가 n일때 2n에 비례

 매체

 방송, 매스미디어 

 전화, 이메일 등

 인터넷(블로그 등) 

 커뮤니케이션

1대 다(일방적) 

양방향 

협업 

select cast(min(sn.begin_interval_time) over (partition by sn.dbid,sn.snap_id) as date) snap_time,  --workaround to uniform snap_time over all instances in RAC

 --ss.dbid,  --uncomment if you have multiple dbid in your AWR

 sn.instance_number,

    ss.event_name,

 ss.wait_class,

 ss.total_waits,

    ss.time_waited_micro,

 ss.total_waits - lag(ss.total_waits) over (partition by ss.dbid,ss.instance_number,ss.event_id order by sn.snap_id nulls first) Delta_waits,

 ss.time_waited_micro - lag(ss.time_waited_micro) over (partition by ss.dbid,ss.instance_number,ss.event_id order by sn.snap_id nulls first) Delta_timewaited,

 round((ss.total_waits - lag(ss.total_waits) over (partition by ss.dbid,ss.instance_number,ss.event_id order by sn.snap_id nulls first)) /

       (extract(hour from END_INTERVAL_TIME-begin_interval_time)*3600 

              -extract(hour from sn.snap_timezone - lag(sn.snap_timezone) over (partition by ss.dbid,ss.instance_number,ss.event_id order by sn.snap_id nulls first) )*3600 --deals with daylight savings time change

              + extract(minute from END_INTERVAL_TIME-begin_interval_time)* 60

              + extract(second from END_INTERVAL_TIME-begin_interval_time)),2 ) Waits_per_sec,

 round((ss.time_waited_micro - lag(ss.time_waited_micro) over (partition by ss.dbid,ss.instance_number,ss.event_id order by sn.snap_id nulls first)) /

       (extract(hour from END_INTERVAL_TIME-begin_interval_time)*3600

              -extract(hour from sn.snap_timezone - lag(sn.snap_timezone) over (partition by ss.dbid,ss.instance_number,ss.event_id order by sn.snap_id nulls first) )*3600 --deals with daylight savings time change

              + extract(minute from END_INTERVAL_TIME-begin_interval_time)* 60

              + extract(second from END_INTERVAL_TIME-begin_interval_time)),2 ) Rate_timewaited,  -- time_waited_microsec/clock_time_sec

    round((ss.time_waited_micro - lag(ss.time_waited_micro) over (partition by ss.dbid,ss.instance_number,ss.event_id order by sn.snap_id nulls first)) /

           nullif(ss.total_waits - lag(ss.total_waits) over (partition by ss.dbid,ss.instance_number,ss.event_id order by sn.snap_id nulls first),0),2) Avg_wait_time_micro

from dba_hist_system_event ss,

     dba_hist_snapshot sn

where

    sn.snap_id = ss.snap_id

and sn.dbid = ss.dbid

and sn.instance_number = ss.instance_number

and sn.begin_interval_time between sysdate-7 and sysdate

order by sn.snap_id