


      19             

  ।稢     䥪⨢ ᯮ짮
⥩ ⥬ ORACLE.  ⮫쪮  ⠫쭮 ࠧ  ਭ樯
ࠡ  ORACLE,  ,  ⭮,  筥 "⮭ ன" ᢮ ਪ
ணࠬ   䥪⨢ ࠡ.

ਬ,   뢠  ᮡ 浪  ᯮ ᫮
 SQL - .    䥪⨢ ࠡ ⠭
᫮  SQL - ,  ᯮ   ⮬  룮 .

㣨 ࠧ ⮩  ᮤঠ ଠ :
    *   䥪⨢ ᯮ짮 ᮢ  ஢
    *  ⨬樨 ࠧ SQL - ஢
    *  ᯮ짮 ᮢ ࠡ⪨

⤥ 짮⥫    쭮  ப   襭
ਪ ணࠬ ORACLE ᨬ  㣨 짮⥫.  
⢥묨  ।⢠       .

   ६       뢠 ⢨ ⤥쭮 짮⥫, 
 20 뢠 ७   襭 䥪⨢  
᭮ ⢨  ࠫ 짮⥫.   ᭮뢠
 ன  ࠬ஢ 䠩 INIT.ORA  祭 㬮砭  .

   ⮬, 䥪⨢ ࠡ ⥬ ORACLE 
  ⥩ 樮 ⥬;  ⠫ ⮣ ⨯
ன    "㪮⢥ 짮⥫  ⠫樨".

砭: ଠ, ᮤঠ  ⮩ , ⭮  ⥪饩 ᨨ
           ORACLE RDBMS  ६ ᠭ ⮣ 㪮⢠;  ଠ
            ꥪ⮬    ॠ.

             ஥஢ 襩 ५樮 ⠡

 蠣  䥪⨢ ࠡ -  ᢮ .   ᠭ
ணࠬ   ஢ ।     ஥஢  .
먣 ந⥫쭮 ⥬   ⨣  襩 ⥯  
  ,   ࠧࠡ⠭  ࠢ쭮 ᯮ  .

         ,   ࠡ⪥,  ᫮  ஢
⠡  ࠬ஢ ,  । (奬 ), 㠫쭮  
࠭祭.  쭮  ᯮ㥬   ⠡    ஭ - 
襩 ⥯ ᯮ짮 २⢠ ५樮 ,   㣮 - 
 襭 ந⥫쭮  ஥ 誠 ( 宩 ࠧࠡ⪥).

    襥  ⥮ਨ ⭮襭  ଠ樨,  ⠪  ࠪ᪮
ਬ (  室騥  ࠭  㪮⢠),   ࠧࠡ-
稪  짮⥫     ᮪  䥪⨢ 㬥
஥஢ ਪ ணࠬ.

     த, ᥣ   ⥩,
 室 ᬮ  ᯥਬ஢   .    
  ⪫     ਭ⮩ ५樮 ⥮ਨ   ⨦
ࠪ᪮ 룮.    २ ५樮   ⮨  ⮬,
  ⢮   ஢     ﭨ 
ਫ.


                                   -- 197 --



⠢  ஭ ஥஢ ⠡,  짮⥫    먣
 䥪⨢   ᯮ짮  ஢ 
ਧ樨.

        設⢮ 権  

ᯮ짮 ᪮  ᭮    SQL - ஢ 
⮬ ४.  ਬ,  ᪮  ᫥饣  
祢:
    SELECT ENAME, DEPTNO
    FROM EMP
    WHERE JOB = 'CLERCK'
    AND DEPTNO = 10
    OR  DEPTNO = 20

⠪   ஢     ᮢ:

1. "뤠   ⤥  મ   ⤥  10     㤭 
    ⤥ 20"   
2. "뤠   ⤥  મ,   ⮫쪮  ᫨   ࠡ 
    ⤥ 10  20"

⨬,  ⨬ 㢨   2:    ⤥  મ,
 ࠡ  ⤥ 20  30. ᫨    㭪樨, 
    ( ᫥⥫쭮 - १) ᪮ ᥬ
᭮     ७. ᫨   ᯮ㥬  㭪樨:
    SELECT ENAME, DEPTNO
    FROM EMP
    WHERE JOB = 'CLERCK'
    AND DEPTNO = 20
    OR  DEPTNO = 30

  १ 稬  મ,  ࠡ  ⤥ 20   
᪫祭 㤭 ⤥ 30:
    ENAME               DEPTNO
    -------------  ------------
    ALLEN                   30
    WARD                    30
    MARTIN                  30
    TURNER                  30
    ADAMS                   20
    JAMES                   20

᫨  쬥  ᪮ (DEPTNO =20 or DEPTNO =30) :
    SELECT ENAME, DEPTNO
    FROM EMP
    WHERE JOB = 'CLERCK'
    AND ( DEPTNO = 20
    OR  DEPTNO = 30 )

  १ 稬  મ, ࠡ  ⤥ 20  30 (
१):
    ENAME               DEPTNO
    -------------  ------------
    ADAMS                   20
    JAMES                   20



                                   -- 198 --



᫨     ᪮    㣮    (JOB = 'CLERC' OR DEPTNO = 20) :
    SELECT ENAME, DEPTNO
    FROM EMP
    WHERE ( JOB = 'CLERCK'
    AND  DEPTNO = 20 )
    OR  DEPTNO = 30

 १    稬  ,     ਠ   㭪樨,  
᫥ 砥  १    -   ન, ࠡ騥  ⤥ 20
  㤭 ⤥ 30 :
    ENAME               DEPTNO
    -------------  ------------
    ALLEN                   30
    WARD                    30
    MARTIN                  30
    TURNER                  30
    ADAMS                   20
    JAMES                   20

              䥪⨢ ᯮ짮 몠 SQL

SQL -  ,     . ᫨  ⠢  몠
SQL  ਪ  ணࠬ, ஢,  ⢨⥫쭮   ᯮ 
 믮 㭪権,     ᯥ稢 . 筮 
।⥫쭮 믮 樨   몥  SQL ,    ,
   몥.

    ஬ ⮣,  ᢮   㭪樨  몠  SQL,  ⠪   DECODE,
SUBSTR  INSTR.   㤥 ࠦ ⮩,   ன ॠ
     묨.
  ஡ ଠ樥    몥  SQL     "ࠢ筮
㪮   SQL".

        ⨬, 믮塞 ⮬᪨

 ࠧ ⪮ 뢠 ࠡ  । ⨬樨 ⥬
ORACLE,  묨    ࠢ   ࠢ 쬠 ᫠.
騥  ࠧ 뢠 樨,   묨   ⮫,
ࠨ ।  몥 SQL.

      ᯮ짮 祢 ᫮ DISTINCT

    ᫨ SQL - ,  ᮤঠ騩 ,  ᮤন     ᪮쪮
祢 ᫮ DISTINCT, ORACLE  ப, 㤠 㡫騥 (᫨
  ).      ࠡ⪨   ࠧ DISTINCT   ᯮ
(   ᯮ짮  㣨  ).

      ᯮ짮 祢 ᫮ GROUP BY

     GROUP BY ࠡ뢠 筮  DISTINCT. ࠢ ப,
ORACLE  ,  ନ  ⮬  㯯  㤠 㡫஢ (᫨
 ).      믮 GROUP  BY  (    
ᯮ짮  㣨  ).

      

      ⮬᪨ ८ࠧ   ꥤ.  ,
ᮤঠ騥 IN     ८ࠧ  ꥤ. ਬ:

                                   -- 199 --



    SELECT * FROM EMP
    WHERE EMP.DEPTNO IN
    ( SELECT DEPTNO FROM EMP )

  ࠡ⠭  ᫥騩 ᪨ , 騩 
ᨭ⠪ 몠 SQL:
    SELECT EMP.A FROM EMP, D:
    (SELECT DISTINCT DEPTNO FROM DEPT)
    WHERE D.DEPTNO = EMP.DEPTNO

㣨  ८ࠧ 믮 ⮬᪨.

      ᮡ  ⢥ ப

᫨ ⠡  ࠧ FROM ࠭஢ 㪠뢠  ⢥  ப,
  ப  ꥤ ᯮ ࢮ.  ਢ ਬ ⮣:
* 㭨    WHERE = ⠭
*   ⢥   १⮬  (ਬ  -SELECT AVG(SAL) FROM EMP)
*  㯠 १ ROWID.

        ᯮ짮 २ ᮢ  SQL - 

ORACLE RDBMS     ⠡  ᯮᮡ:
* ᯮ  ᪠஢ ⠡
* ᯮ 

ᯮ짮 ᮢ  ࠪ᪨  ᥣ  ।⥫쭥 
᪠஢ ⠡.   DML (ᮡ -  SELECT, UPDATE   DELETE)
筮 ᮤঠ ࠦ,  ।騥     祭 
᪫祭;  ਬ  -      㦠 । 
   ஦, 室騥   .    
⢨  אַ   室 ப.

     ᬮ ⠡ ।⥫쭥, ᫨  ,  ᮬ
㤥 ࠭  25 業⮢ ᥩ ⠡;  ⮬ 砥 ᯮ짮
    ᪠ ᥩ ⮫쪮   室  ⥭ 
  ⠡   .

         ᫥ :

* ᫨  뫠  ।.  । -      롮,
ᯮ㥬  祭 ப  १  ᪫祭 .  ਬ,
᫥ ࠧ WHERE ᮤন  ।:
        WHERE DNAME = 'DEVELOPMENT'
        AND SEX != 'FEMALE'

* 㥬 ⮫   㭪樥  䬥᪮ 樥

 㤥 ᯮ짮, ᫨ ⨬ ,   室騩 (᪮쪮
᫥ ࠧ  뢠  롮,    ORACLE  ᭮
 ⥫,      ஫)

  㤥 ᯮ짮  ᫥ :
*  ࠧ WHERE
* । - ᯮᮡ   ⮫ (१ 㭪
   䬥᪮ ࠦ)
*  ᪠   祭 NULL  NOT NULL    ⮫ (
  砥,     ।  ᯮ "IS NULL"  "IS NOT NULL").

                                   -- 200 --



      ᯮ짮,  ᫨ ⮫   ஢ 
ਢ   롮.    ਬ ।⮢,   
 㤥 ᯮ짮:

    WHERE SAL * 12 = 24000
    WHERE SAL + 0 = 500
    WHERE ' '||ENAME = ' Smith'
    WHERE SUBSTR(ENAME, 1, 1) = 'S'

 ࠢ "㥬 ⮫    ஢"   
᪫祭:  ᯥ樠쭠 ⨬  宦 ᨬ쭮 
쭮  祭  ᪠    SELECT ᯮ짮 ࠦ,
ᮤঠ:

    { MIN | MAX | ( col { + | - } constant }

  ᮤঠ 㣨 ⮫殢.  ਬ,  ࠦ 㤥 ᯮ짮
:

    SELECT 2 * MAX (SAL + 1) FROM EMP

       䥪⨢ ᮢ

 ।⢮ 襭 ந⥫쭮   ⥭஢
.  ᮡ  ୮ ⮣,    믮  
⮫쪮  ⥭       ࠣ  .

 ᫥ ਬ ।,   ᮧ  ᫥騩 ⥭஢
:
    CREATE INDEX INDNAME_CITY_STATE ON
    EMPLOYEE (LAST_NAME, CITY, STATE)

 १ ⮣,   ࠧ  WHERE  ᯮ       ⮫,   
 ᮧ  (ᨬ  㣨 ⮫殢,   )
 㤥 ᯮ짮:

    SELECT ...
    FROM EMPLOYEE
    WHERE LAST_NAME = 'SMITH'
    AND CITY = 'FREDERIK'
    AND STATE = 'MD'

᫨   ࠧ WHERE  ᯮ짮 ⮫쪮    
⮫,    ⠪ ᯮ짮,     ᥫ⨢,  
।饬 ਬ.

    SELECT ...
    FROM EMPLOYEE
    WHERE LAST_NAME = 'JONES'

  㤥 ⠪ ࠧ   ⮫쪮  , ᫨ 
롨ࠥ ⮫ ஢:

    SELECT SITY, STATE
    FROM EMP
    WHERE LAST_NAME = 'JONES'



                                   -- 201 --



 ᫥  ਬ  ᯮ짮  㤥, ⮬  ࠧ
WHERE  ᮤন ࢮ ⮫ :

    SELECT ...
    FROM EMPLOYEE
    WHERE CITY = 'BLACKSBURG'
    AND STATE = 'MD'

    SELECT ...
    FROM EMPLOYEE
    WHERE STATE = 'DC'

    ஥ ࠧ묨 ᯮᮡ ⠪, ⮡ ᯮ짮
  ᯮ짮 .  ᫥ ਬ ⨬,  ⮫ HIREDATE
।  DATE   㭨 .  :

    SELECT * FROM EMP
    WHERE TO_CHAR(HIREDATE, 'Month dd, yyyy') = 'January 14, 1986'

 ⮫ HIREDATE 㭪樥 TO_CHAR, ᫥⥫쭮  ᯮ짮-
  㤥.    ६  ᫥饬  㭪樥 TO_DATE -
 ⠭,   ⮫ , ᫥⥫쭮  㤥 ᯮ짮
 ᪠  .   饬 砥,   ࠪ⨪ ᯮ짮 ⠭,
ਬ塞  롮થ,   ࠢ  묨, ।묨  ⠡.

騩 ਬ ⠪ 㤥 ᯮ짮 :

    SELECT * FROM EMP
    WHERE HIREDATE = '1-JAN-86'

          ⢥ 

    ⨬,  ⮩   ⢥ ⠡  ।
뫠    ஢  ⮫.  ᫨  ⥬ ORACLE । 
     ᯮ짮,    㤥 ᪨ 饥 祭 
,   ᪠஢ ⠡. (஢ -  ᫥⥫
ᬮ ⠡,   ६   -     १ ).
⥫쭮, ⥬   ᪠஢ ⠡,  ⠪  ᪠஢
.

ᬮਬ :

    SELECT EMPNO, ENAME FROM EMP
    WHERE JOB = 'CLERK'

 ⮫쪮 ⥬ Oracle ।,   ⮫  JOB    (
㭨,  ,    㦥   , 㭨),   㤥
᪠  ॡ㥬  祭      ('CLERK')  ୥   
祭 'CLERK'.

        祭 NULL

    ᫨  ,  । ⮫    ⠡    NOT NULL; 
 믮    ⥫쭮  ᮢ. ᫨ ।
ᮤন   ᫥ ࠧ:
    IS NULL
    IS NOT NULL


                                   -- 202 --



  ᯮ짮  㤥.   ᫨     
  祭  (..    祭  NULL),   SQL - ,
 㤥 ࠡ뢠  ᯮ짮 .     ᤥ
     ᮬ ப,  ᮤঠ 祭 NULL.

ਬ, ᫨   ᬮ  㤭,  ᨮ (
ᨮ NOT NULL),    ᫥騥 :

     1:                                   2:
    SELECT * FROM EMP                          SELECT * FROM EMP
    WHERE COMM IS NOT NULL                     WHERE COMM >= 0

 ।,   ⮫ COMM  ,  ⢥ত, 
  㤥 ᯮ짮   1,     2  㤥 ᯮ짮
 祭  १⮢   믮  ᪠஢.  , ᫨
設⢮ ᥩ  ⠡ EMP ( 25%)  祭  ⮫ COMM,
 1 ।⥫쭥.  2 ।⥫, ᫨ 設⢮ ᥩ
 祭 NULL  ⮫ COMM.

      ᪮쪮 ᮢ   ⠡

, ᮤঠ騩    ।⮢    ⠡, 
ᯮ짮 ᪮쪮 ᮢ, ᫨:
    *    㭨묨
    * ।  ࠢ⢠

, 頥   , "᫨"  ࢨ  १⮢
 祭 筮 १. ᪮쪮 ᮢ  ᯮ 
।⮢ ⨯ "࠭祭    ࠢ⢮" (⠪ : DEPTNO != 10),
 ਬ:
    SELECT *
    FROM EMP
    WHERE JOB = 'MANAGER'
    AND DEPT != 10

 ⮬ ਬ  㤥 믮 ⮫쪮    JOB.

      롮  ⢠ ᮢ

   ᪮쪨 㯭묨 ᠬ,  騬  ।⥭,
ORACLE 롨ࠥ 騩   ᭮ ⨯ ᮢ (㭨 
):   ⠪ - ࠪ⨪ ⮫殢.

    ᫨ 㯭  㭨,  ⠪    㭨  , ORACLE
ᯮ  㭨     㭨,  ⠪
ࠧ,  "᫨ﭨ". ⨬,  EMPNO - 㭨 ,  SAL -
㭨, ᬮਬ :

    SELECT ENAME
    FROM EMP
    WHERE SAL = 3000
    AND EMPNO = 7902

     믮 ⮣  ORACLE 㤥 ᯮ짮 ⮫쪮  EMPNO.
᫨  ப  祭 EMPNO = 7902, ஢ ॠ쭮    SAL
  ।   宦   祭 3000  ᯮ짮  SAL.



                                   -- 203 --



    ᨬ쭮  ᫨   (5) ᮢ.  ᫨    
ਥ (।⮢ ࠧ WHERE), ᫨ 㤥    ᮢ,  
⠢訥  ஢ ""  楫  , 㤮⢮騥
⠢訬 .

       ᯮ짮 ᮢ

       室騥     ᫨,    ⠪,  
ᯮ짮 ᮢ ᭨ 䥪⨢ (- ⮣,    
।   㤥 ᯮ짮   ⨬ ).
㣮 ਠ: ⠪    ᯮ   ᮢ,   ᠫ
SQL - ,  뫠  祬    ⮫殢  
 ᯮ짮 " 稬" ᮢ.

    ⮡    ᯮ짮 ᮢ,    ᯮ ""
㭪  ࠦ  ⮫, 祩     ᯮ짮.
筮   ᫮   ஢ ⮫殬  ⥭樥 ⮩
ப    ᨬ  ⮫殬, ਬ:

    SELECT ENAME, DEPTNO, SAL
    FROM EMP
    WHERE DEPTNO + 0 = 20
    AND ENAME = 'SMITH'

        ⨬ ࠧ SQL - ஢

ORACLE RDBMS 믮 ࠧ ⨬樨  襣 ⥫⢠; ஬
⮣, ⭮ 뢠 । SQL - ,    
  䥪⨢.   ࠢ ⥩, 室  ࠧ
,  ᯮ짮 ஬  EXPLAIN.  㬥  ⮬
 室   䠩 EXPLAIN.DOC,  ⠢饬  ਡ⨢
⥫.

      ⨬ ᮢ (SELECT)

 쪮 ⠡ ORACLE     ஥ ᫥⥫-
 ᪠஢    ⮬ 砥  㦭.  ᫨  -
頥  25 % ப 让 ⠡, ᯮ짮   ᮢ  ஢
 ⥫쭮 㬥 ६ ࠡ. ᫨ ⮫  ⠡,
騥  ࠧ WHERE,  ஢  ਧ,  㤥
믮 ⥫쭮  ॥,  祬    ᯮ짮    ।.

   ࠧ  WHERE ᯮ  ⮫殢 (஢,
ਧ  - ), ORACLE 롨ࠥ,  ᫮ ஢ 
(..  - ਩  ⮫ 㤥 騬  ).

ਬ - 業 ࢮ ।  ࠧ WHERE ᪫砥 75% ப 让
⠡,   ६  業 㣮 ।  ᪫ ⮫쪮 15%.

oRACLE ᯮ ࠧ ७     롮 窨 (뢠
"騬" ⮫殬  ᫮),  ன 稭 ஢  ᥬ
ࠦ ࠧ WHERE.

    ,   ⨬  ६  ६ (  
ᨨ) .  ᪮ Oracle Corporation த ᢮ ᫥
ᮢ ⨬樨,   ᨨ   ᨨ ⥬   롨 ࠧ
 ⨬樨    ⮣  .


                                   -- 204 --



  騥 ࠢ ࠢ ࠧ ⥩:
    ॥                     祬  
    
    ஢ ⮫               ஢ ⮫
    㭨                    㭨 
    ROWID (=⠭)                    㣮 
    ࠭祭                 ࠭祭 
    ࠢ  ࠧ  'x%'       -------"-------- '%x%'

              ⨬ 栭 (NOT)

    ORACLE  ᯮ   ।⮢, ᮤঠ ࠦ "
ࠢ" (!=  NOT=),    ᯮ짮   㣮 ।.
ਬ,  ࠦ:

    WHERE X != 7 AND Y = 8

   ᯮ    ⮫ X,   ᯮ  ⮫ Y.
筮     "NOT="  ⢮  頥 ப ,  祬
⢮ ய饭.  ORACLE  ⥭   ⥬ - ⠡
稢  ⥫  /뢮.   ࠧ,    
॥   ᪠஢ ⠡,  ᯮ짮 .

᫨ ।  ᮤন  NOT      㣨  ﬨ, ORACLE
८ࠧ   , 騩 ᯮ짮 :
  室            ८ࠧ
    
    NOT >                   <=
    NOT >=                  <
    NOT <                   >=
    NOT <=                  >

          ⨬ 樨 OR

    SQL - , ᯮ騥  OR,  묨 ࠭祭ﬨ 
ࠡ  ᠬ.  饬 砥, ⨬  ந,  ᫨
騥  樨 OR ⮫  ஢,     
믮, ᫨  ⮫ ஢,   - .

⨬,  :
    SELECT *
    FROM EMP
    WHERE DEPTNO = 10 OR JOB = 'CLERK'

 ஬  ⮫ -  DEPTNO,    JOB  -    .  ORACLE 㤥
ᯮ짮     믮 - த ꥤ ᫥
ᮢ:
     1:                               2:
    SELECT *                               SELECT *
    FROM EMP                               FROM EMP
                                           AND DEPTNO != 10

   ⮬,      ᯥ   砫 ᯨ᪠
।⮢ ( ,  ய᪠騩 襥 ⢮ ᥩ).  ⨬  
 ⢮ ஢ப ⨯ " ".




                                   -- 205 --



।, 易 ᫮ OR,   ᫥     ᯮ 
⨬樨:
    *  SQL -  ᮤন ࠧ CONNECT BY
    *  SQL -  ᮤন 譥 ꥤ
    *  ⥬ ORACLE 蠥,   ᯮ짮 ᮢ  ⨬
      믮 .

஬ ⮣,  ⨬ ਬ   ࠧ  IN,   ࠭᫨ 
OR.  ਬ, ᫥ ࠧ:

    DEPTNO IN (X, Y, Z)
    OR DEPTNO = Z

砥  ,  :

    DEPTNO = X OR DEPTNO = Y OR DEPTNO = Z

              ணࠬ ஢/ꥤ ⥬ ORACLE

ணࠬ ஢/ꥤ  ⥬ ORACLE ᪮ 믮 ⠪
権 : CREATE INDEX, SELECL DISTINCT, ORDER BY,  GROUP BY  
ꥤ.   ,  ,    㯮冷祭,
ᯥࢠ ࣠  ७ ஢    ।   ⥬
᫨  , ஢ ਠ.

 ࠡ ணࠬ ஢/ꥤ   ࠬ;  稭
 䨪 SORT  ᠭ  ਫ D.

஬ ⮣,   ࠡ   ࠡ稥 :

internal          ࠧ ⠭ ࠬ஬ 䠩
(७)     INIT.ORA - SORT_AREA_SIZE.

external           ᯮ   -
()         १⮢    ६ 믮 ꥤ
                 (᫨ﭨ).   ࠡ  । 
                 ६ ᥣ.   襬 砥 ࠡ  
                  ࠧ,  ॢ騩 ࠧ  ⮫殢.
                  ᯮ  饣 ᫨ﭨ.

        ⨬ ORDER BY

    ⨦ 㯮冷祭  ᪮쪮 ᯮᮡ ᠭ
SQL - ,  ࠭஢   ⮫쪮 稥   
ࠧ ORDER BY.

冷祭 १,  稢訥      ᯮ짮 ORDER BY,  
᫥  ⥬ ORACLE    㯮冷祭묨. 
ࠧ, ४  㯮冷祭   ࠧ ORDER BY.

 , ᮤঠ饬 ࠧ ORDER BY,  ᯥࢠ 롨,  ⥬ 㦥
      㯭  ᮢ,    ணࠬ
஢/ꥤ.

      ⨬ GROUP BY

 㯯஢  砫   ࠧ WHERE  室  ,
 騥 ࠡ⪥.  ਬ ᫥騩 :

                                   -- 206 --



    SELECT JOB, AVG(SAL)
    FROM EMP
    WHERE JOB != 'PRESIDENT' AND JOB != 'MANAGER'
    GROUP BY JOB

,  祬 ⠪:

    SELECT JOB, AVG(SAL)
    FROM EMP
    GROUP BY JOB
    HAVING JOB != 'PRESIDENT' AND JOB != 'MANAGER'

  稭:

    1.    2  ᮤন ࠧ WHERE,  騥 ப
    ࠡ  ࠧ  GROUP BY.     ப, 
  ய饭  㤠 ࠭     ࠧ WHERE.

    2. ࠧ HAVING ᯮ  㤠 ,  㯯஢ 
।  (ਬ -   쭮   ।).
 ᨭ⠪  ࠧ  祭 ࠧ WHERE,     (,
᫥⥫쭮,  ) ᯮ짮 塞  WHERE.

      ⨬ ꥤ

 ਢ ᭮ ࠢ    ⨬樨  믮 ꥤ:

    * ⮫,  ᯮ㥬  ꥤ,   ஢ * SQL -
   ᠭ  ⮬  ᯮ짮 ᮢ,    
 (᫥, ⮡ ଠ ᠭ SQL -     ᬮ  
⨫  ᯮ짮 ᮢ) *  ᯮ짮 ꥤ  ⠡,
 襥 ⢮ ப, 祬 襥

      ஢ ꥤ

᫨ ⮫,  騥  ꥤ,    ஢,  믮
᫥ ᫮ 믮  "஢ /ꥤ":

    * ᫨      㣮  ᯮᮡ  믮   (᫨ ORACLE
      ।,    ᯮ짮 ,  㤥 ᯮ짮 , 
       ஢/ꥤ)

    * ࠧ ꥤ   ᫥饣 :
         tab_a.expression = tab_b.expression
          ਬ:
         tab_a.col_a + 1 = to_number (tab_b.col_b)

    ਬ - ꥤ   ᮤঠ "  ࠢ".

 ஢/ꥤ  ꥤ塞 ⠡  ࠡ뢠 ⤥쭮,
⥬ 室騥  .   ,   ஢ ⥩
᫨  ᯮ짮 ࠦ, ନ饣 ꥤ.

᫨   ⥫  । ⡮ (ਬ - DEPTNO = 20),
  "ᥫ⨢" ।   ᯨ᪠.

      ஢ ꥤ


                                   -- 207 --



᫨ ⮫쪮   楯塞 ⠡    ,  㣠 ⠡  㤥
饩    믮  .  ਬ,  ᫨ EMP.DEPTNO ஢,  
DEPT.DEPTNO - ,  ⮣  ᫥  DEPT 㤥 饩 ⠡楩:

    SELECT ENAME, DNAME             SELECT ENAME, DNAME
    FROM DEPT, EMP                  FROM EMP, DEPT
    WHERE EMP.DEPTNO =              WHERE EMP.DEPTNO =
         DEPT.DEPTNO                     DEPT.DEPTNO
    AND JOB != 'SALESMAN'           AND JOB != 'SALESMAN'

᫨   楯塞 ⮫   । ᫥饣 롮
 , ORACLE ந  㯠  ᮮ⢥⢨   
"ᥫ⨢"  (⮡    ப ᥪ  ࠭ ⠤
ࠡ⪨)    롮 ⨬쭮 .  饬 砥, ORACLE
ᬠਢ:
    *  ।  ᯮ짮 
    *   㭨

 ஥   ந⥫쭮 ⠪  :
    * ⢮ ப  訢 ⠡
    * । ,  㭨 

    ⢨⥫   ⥬ ORACLE 롨ࠥ   ᭮
訢    ⥩   ⭮襭     ᮮ⢥⢨  奬
࠭஢  (.  .  19-1).  ஢ ।,  ⠡ 㤥
饩 ⠡楩 .

      , :

*  ।,  楯   祢 ᫮ AND, 
  ᨬ  ᮮ⢥⢨   祭ﬨ,  㪠묨  . 19-1 稭 
   ()  訬 ().

* ⥭஢  砥  , ⠢  ᪮쪨
  ⮫殢 ⠡,   
* ꥤ   ⢥ ⠡  ᮢ,   
   楯   ⮢ ந.
* ᫨ 祭 ࠭ ࠢ,   ᮢ , ORACLE ᯮ  ⢥
  饩 ᫥ ⠡  ࠧ FROM.

⥫쭮, 室 訥 ⠡  訬 ᫮ 室 ப
ᯮ  ࠧ FROM -  ᫥,     ᠭ ⠡
ꥤ (3   ⠡) ᯮ  ⠡  
१⮬ ࠭஢   ꥤ.

 ᫨   ⠡  让 १ ࠭஢  ᪠,
    楯  㣨 ⠡栬  ᯮ짮 , 
⢥ 饩 㤥 ࠭ ⠡,    楯 
ᯮ짮 . ⥫  ࠭஢  ꥤ ᥣ
८  ᮢ㯭 १⮬.

  ࠭, ⥬ ॥  㯠
            
    1           ROWID = constant
    2           㭨쭮 ஢ ⮫ = constant
    3            㭨 ⥭஢ = constant
    4              = ᮮ⢥饬 ୮  
                㣮 ⠡ ⮣  

                                   -- 208 --



    5              = constant
    6            㭨 ⥭஢ = constant
    7           㭨  = constant
    8            ⥭஢  =  ࠭
    9           ᯥ஢ 砫 ⥭஢ 
    10          㭨쭮 ஢ ⮫ ᯥ஢  
                ࠦ BETWEEN ... AND ...; 㭨쭮 ஢
                ⮫ ᯥ஢: LIKE 'C%' (࠭祭 )
    11          㭨쭮 ஢ ⮫ ᯥ஢  
                ࠦ BETWEEN ... AND ...; 㭨쭮 ஢
                ⮫ ᯥ஢: LIKE 'C%' (࠭祭 )
    12          㭨쭮 ஢ ⮫  ⠭ (-
                ࠭祭 )
    13          㭨쭮 ஢ ⮫  ⠭ (-
                ࠭祭 )
    14          ஢/ꥤ (⮫쪮 ꥤ)
    15          MAX  MIN  ⢥ ஢ ⮫
    16          ORDER BY   
    17           ᪠஢ ⠡
    18           ஢ ⮫ = constant  IS NULL  LIKE
                '%C%' ( ᪠஢ ⠡)
    㭮 19-1 ᮡ ᮢ, ࠭஢  ᪮

        ୠ ࠡ⪠

     ୮  ࠡ⪨  ६ ࠡ
᪮쪮 ப.  ந⥫쭮 ⠪ ࠡ⪨    ࠧ
ॢ ᪮ ࠡ⪨ ⤥ ப.  ।⥫쭮
 ࠧ୮ ᨢ  100     ப.   ⨫
 ⮩   ᭨ ६ 믮.

    짮⥫   襭  䥪⨢    ᯮ짮
ᨢ    ஢  INSERT    SELECT  몠 ணࠬ஢.
ᠭ 맮  ⨯  ਢ  ᮮ⢥ 㪮⢠  
몠 ணࠬ஢,  ਬ "㪮⢥ 짮⥫  Pro*FORTRAN"

          ୮ ࠧ  뢠 ६

    । ⥬,  SQL -  㤥 믮,   ஠஢
஬   ६   易  ஬. ६, 稢
  樨,    - ᥪ㭤; 筮  
७.

   ६, 稢  ⮢ ,   ⥫ 
饣 ६ ࠭樨.  ୮  ࠭権,   ᪮쪨
஢   ६ ⢥.

४ ।      樨      ப:  HOLD_CURSOR=YES
  REBIND=NO  ࠭ ஢ 묨  ⠪  ࠭ 易
६   ࠧ࠭  SQL  - .  ⥫쭮, 
࠭,     ஢ ୮,  ᫨  
 믮  ࠧ.

ਬ,    ⮢  ࠭樥, 饩   ⪮
஢, ६ ⢥  ᯮ짮 HOLD_CURSOR=YES  REBIND=NO
᮪⨫  20  4 ᥪ㭤.

              20          

                                   -- 209 --



       ᭮  DBA  "ன" ⥬ ࠢ 
  ᯥ祭 ᨬ쭮    䥪⨢ ࠡ 
짮⥫ .  ⮩  㦤 ⢨,  筮 믮塞
஬      짮⥫ .

       뢠  ᭮  楤 ன,   ⠪ ᯮᮡ
ॣ㫨஢ ࠡ ࠧ ⥩  ORACLE.     ᢥ 
ன ⥬, ࠧ ᪨ -  뢠   21.   ⮣,
 ४樨    ன ⥬     ⭮ 樮
⥬      ᮮ⢥饬 "㪮⢥ 짮⥫  
⠫樨".

    ORACLE RDBMS ন DBA  窨 ७  ன  ਭ.
ன   믮 ࠧ묨 ᯮᮡ, ਬ - 㯮冷祭
ࠧ    ஢ ࠬ஢ 䠩 INIT.ORA. ਭ
ࠡ   믮   ॣ୮ ᬮ  
ଠ樨, 뤠  MONITOR ⨫ SQL*DBA.

        ᭮ 楯樨 ன 

ன   -  ᭠ ,   ॡ
⥫쭮  ६   ᨫ.    砥  ᥡ ⢮
䠪஢; ਬ -  ।   ᫮ ࠡ  ࠬ 
  ६   ப ।.  ࠪ⨪  ,
ॡ   ⮫쪮 ,     ࠭஢ ࠢ
襭 䥪⨢.  ᬮ  ,  ४⨢  楤  ன
⥬ ORACLE  ࠧ  ᪮쪮 ஢.  ⮩   ⪠
饭  饭 楯権 ன.

⥪ ORACLE RDBMS Version 6 ᮤন  , ᯥ樠쭮
।祭  ᮪ ந⥫쭮,    ᥡ:
    * ஢  ஢ ப
    * ᢥ 

    ஢   ஢  ப   ࠫ쭮 믮 ⠢ 
    ⠡  ⮫,  ᪮  
७樨   ஢ ⤥ ப.  ᢥ  砥,   ⮫쪮
᪮  ।⠢    㦤        
襭 ,   ᫥⥫쭮  ॠ    㤥
ᢥ.  ࠭樨    ᫥ ⢥  
ୠ, ᫨   ६  ⮢  믮 commit.

᮪ ࠫ쭮 ࠡ ORACLE  RDBMS  Version  6    
 ᯮ짮  ᫨⥫ 魮, ।⠢塞 묨
設.    設  筮 ।⠢  ᫨⥫  魮
 ⭮襭  業  ࠢ  묨.    魮 CPU
⥫쭮 । 宦 ࠭樨  ORACLE RDBMS Version 6,
⨯୮ 祭 룮.

 ᭮ 楯樨 易  ன :
    * ⨬ ᯮ짮 
    * ⨬ ᪮ /뢮

    㣨 ᫮,   ⨬஢  ந⥫쭮  .
 ன ⮨  㧪  ()  /뢮.  
⨬쭮 ஥ ⥬  CPU, ⠪  ᪨ 㦥   100
業⮢.


                                   -- 210 --



       ॡ 짮⥫

    ।뫪 ன  ⥬    ᮪䥪⨢ ࠡ 
  ⥪   ॡ 짮⥫  ⥬. ,
ਬ,   ⠪ :

* 쪮  । 짮⥫  㭨묨   ६
  ࠡ  ⥬ ?
*  ᨬ쭮 ⢮ 짮⥫   ࠡ 
  ⥬ ?
*  ⢮ 짮⥫ 㤥 믮 । ⢨ ?
  ਬ -  ⢮ 짮⥫  㤥  - 짮 SQL*Forms, 
   ६   ⠫ - Pro*FORTRAN?      짮⥫
  믮  SQL*Plus   ᯥ- 樠쭮 ⨯ ?
*  ப ᯮ㥬 ਪ ணࠬ:  ।  ᨬ쭠
   ࠭樨?
*  ⭠ ଠ 室?  - ⥫쭠 ?
*  ⨯ SQL - ஢   ਬ  ப ᯮ㥬
ਫ ?    짮⥫ 뤠    讬  
 ⠡ ?  ॡ    ६ ᥣ⮢ ?    
짮⥫  ᮧ-  ⠡   ਢ ?
* ᪮쪮 ᫮ 㤥 奬   ?    ⠡ ଠ 
  䠩 樮 ⥬   ८ࠧ  ⠡ ?
* ⥫쭮   롨    ?

       ࠨ 䥪⨢ ?

 䥪⨢ ன ᢮       
ந⥫쭮.   ᯮ짮 ᪮쪮 誠  ⮢ ७,
 ᠬ  -   筮 ।,    ⢨ 
ன ਢ   १⠬.

     ࠧ,  -        ࠭묨 ⠬
(ࠬࠬ).  室 ஢ ⥫쭮 ᫮ ७  ᨫ쭮
 ᫠ 㧪 ⥬,    ⠪     権.
 ७    祭 稭,  ᫥⢨
⥫쭮 .

          ஢ ன ⥬

ᯮ ⥬᪨  室  ன,   ⨣ 
१⮢   ⪮ ६.

ன ⥬    ந      ஢,   
室  ࠬ ⮩ .  ⮣,   㯭  
  ⠫樨    ᮧ  ( 砫  ଠ쭮 ࠡ),  
  ᯮ짮   ६  ᯫ樨 .

ன SQL  -  ஢ । ⨬쭮 ᯮ짮 몠 SQL.
  設⢥ 砥     १, ᯮ
᪮쪮 ਠ⮢ SQL - ஢,   ⬥  ࠧ
ந⥫쭮  ᨬ  ਬ塞 ᨭ⠪.  ﭨ 
ᠭ SQL - ஢  ந⥫쭮 㦤    19.

⨬ ࠧࠡ⪨ ਫ 砥 ਬ  ਪ ணࠬ
㬥⠫   ।,   ⠪    SQL*Menu, SQL*Forms,  PRO* -
४.   ப ࠧ  ᫥    .
室   - 樨   ⭮ த.

                                   -- 211 --



    ன     砥   ᥡ ᯮ짮 ⥮ਨ
ଠ樨  ࣠樨   ⠡    ,  ⠪ 
ᮧ    襣  ᮢ.  ⥮
ଠ樨, 奬   ࠧࠡ⪠ 室   ।  
,   ⮬ ࠧ  ॢ室 ⥪.  5  16
㦤     ᯮ짮.   19 㦤
ᯮ짮 ᮢ.

    ன 䨣樨 ORACLE RDBMS 砥  ᥡ ᭮ ࠢ쭮
ਬ ६ ࠬ஢  䠩  INIT.ORA.    ⥬  뢠  
 ,   ਫ D ᮤন  ᠭ 䠩 INIT.ORA  
ࠬ  ⤥쭮.

    ன 樮 ⥬ 砥 讥 ⢮ ⢨,
  ᨬ  樮 ⥬.   ⮩  ਢ
ਬ ⠪ ன;  ⠫쭮 ᠭ    ᮮ⢥饬
"㪮⢥ 짮⥫  ⠫樨".

    ன  ⮨    襬  ᯮ짮 㯭
㤮 (,  ᪨,  ।⢠ 裡)  ᭨ ⨢
/뢮  ஢  㧪.   ⥬ 뢠   ,
 ⠪ ⥬ᨬ  ⠫  ᭨  "㪮⢥ 짮⥫ 
⠫樨".

      ᭮ ।⢠ ன

 ⥬  ORACLE RDBMS ᮤন  ।⢠,   
ன ஬ .    ᥡ:
    * 䠩 䨣樨 ⥬ (INIT.ORA)
    * ࠢ ࠬ
    * 䮭  DBWR
    * 䮭  LGWR
    * ᥣ ⪠.

        ன  ६ ⠫樨

 ⢨  襭 ந⥫쭮   ।ਭ
⮫쪮  ⠯ ⠫樨.  ⢨ ਬ⥫쭮  
樮 ⥬ 뢠  "㪮⢠ 짮⥫  ⠫樨";
  ଠ ਢ .

      ਬ ⢨  ன 樮 ⥬

ଠ, 宦  ਢ 뢠  㪮⢠  ⠫樨:

* ।  ⠫  ᯮ 䠩 ⥬ ORACLE
* ॡ  ४樨  譥 
* ॡ  ४樨  ⨢ 
* ਢ  ਮ ᮢ
* २⢠ ࠧ塞  ORACLE
* ।⥫ ன⢠ 譥  (ਬ -  ᪮  )
* DMA (direct memory access - אַ   )
* ᯮ짮 ⥬   㧪

      祭 ਮ⮢ ᠬ




                                   -- 212 --



ᥬ ᠬ  ⥬ ORACLE   ਮ. ⪠
  ਮ⮢      ந⥫쭮 ⥬  
ਢ   १⠬. ⥫ ଠ .  "㪮⢥
짮⥫    ⠫樨".

       ࠣ樨 ᪮

ORACLE RDBMS  ᥣ   ᪠,  ᫨   䠩
ᯮ  ᪥ 뢭.   ᯮ  , ᮧ
䠩 ⥬ ORACLE  ⮬ ᪥    ᯮ ணࠬ ⨬樨
᪮ ( ,   ORACLE RDBMS ⠭).

        孨 ன ன

 ⮬ ࠧ 뢠     ᯮᮡ,  
  ⥫쭮    ந⥫쭮 襩 ⥬.  
 ⢨    ॡ 㡮  ⥬ ORACLE  ।
᫥  ந⥫쭮.  ⠫쭮  ਢ  蠣
ᬠਢ  ᫥ ࠧ ⮩ .

*  䠩 ୠ ୮ 믮  ன⢮, ⫨筮 
  䠩 .
*   ஫ 祪,  㢥稢 祭 ࠬ
  LOG_CHECKPOINT_INTERVAL 䠩 INIT.ORA.
*   । ୠ,  㢥稢 祭 ࠬ
  LOG_ALLOCATION.
*  ࠧ SGA   㢥祭 ࠬ DB_BLOCK_ BUFFERS.

*    ᥣ ⪠ SYSTEM ᮧ ⥫ ᥣ.

        ⨬ /뢮

 㢥祭 ᫠ 짮⥫, ६   , 㢥稢-
   ஢  /뢮.  楫  ⮬ ᫥ 
  ᥡ:
    * ஢  ࠧ ⨯ /뢮:
       *   䠩 ୠ
       * ⥭  䠩 
       *   䠩 
    *  ᪨ 祪  /뢮
    *  ⥩ /
    * ⨬  묨  ࠬ SGA  ᪮
    * ᯥ祭 ண /  䠩 ୠ.

 ⨬쭮 ਠ   뤥 ,     㤥
६  饭,    ।   ࠧ ᪮ ࠩࠬ.
  ᨬ쭮 ᯠࠫ  ᢥ  㬠 ७
/.

⢮  /뢮  ࠧ묨  ᯮᮡ,  ᫥騥:

* ᯥਬ஢  ࠧ묨 ࠬࠬ  ⤥ ꥪ⮢ 
* ⨬ ᯮ짮 ᪮  ⥬  ࠧ饭  䠩  
  ࠧ ᪠
* ࠧ   ᮢ ࠧ饭   ࠧ ⠡
  ࠭⢠
* ⨬ SGA


                                   -- 213 --



      ਭ /   SQL*DBA

⮡ ᬮ  䨧᪮  ᫮  ⥭  ᥩ   ⭮⥫쭮
䠩,  ᯮ짮  MONITOR FILE.  ਬ ᯮ짮
⮩     樨 १⮢   ਫ .

      ᯮ짮 ⠡ ࠭  㬮砭

᫨ ࠫ쭮      짮⥫,  䥪
  ࠡ  ।   ࠧ ⠡ ࠭⢠.
 । 稥   ᪮쪨 ⠡ ࠭,   ⠪ 
䠪,   祭  ࠭ 믮  砩 ࠧ,  
      짮⥫.

ਬ ᯮᮡ 祭 ⠡ ࠭    ᥡ:
* 祭 ⤥쭮 ⠡筮 ࠭⢠, ᯮ㥬  ᭮ -
   ६ ᥣ⮢
*   ᮧ ꥪ⮢ 짮⥫ - 祭  ࠭⢠, ⫨筮
   SYSTEM
* 㯯஢  짮⥫ ⤥ ਫ  讬 ⢥
  ⠡ ࠭    ࠭⢥, ।祭  
  ਫ.

᫥ ਬ 뢠  쬠 ࠧ ,   
  ।⥫쭠    ,  ⠪   㣨 稭,
ਬ - ⥣ 娢樨  ⠭, ⠪ 뢠 ﭨ 
।⥭ 롮 ⮩   奬 ⠡ ࠭.

       ⢠ ⥭⮢

     設⢥ 砥 祬  ⢮ ⥭⮢  ⠡ 
, ⥬ .  ᪫祭  " ⠡"  (뢠
) RDBMS  䥪⨢ ࠡ⠥  ⠡栬  ᠬ,  騬
  ⥭,   祬  ⥭묨 ⠡栬.  ᯮ짮
讣 ⢠ ⥭⮢  ஢  室,
易  㯮   ப.

     㬥襭 ⢠ ⥭⮢ ᮡ 먣뢠  ᪠஢
⠡.  ᪠஢ 믮    묨, ᯮ묨
 ᪮쪨 ⥭ ⠪   ய᪠     ⠡
ᥣ    맢  । ⥬   ⥭ 㤥 .

    ⮡ ᬮ,  ᪮쪮 ⥭⮢  ⠡  , 
 USER_SEGMENTS ᫮ .

⮡ ஢ ⢮ ⥭⮢, ᯮ  (
᪮쪨)  㪠 ⮤:

* ᮧ  ⠡  砫 ।,   ᥩ ⠡.
  (ᮡ  ⭮  ⠡栬,   ᢮ ࠧ஢).
* ॣ㫨 ࠬ  ⠡      ⠪ ࠧ, ⮡
  ᯮ짮  ࠧ 訩 ⥭ (㢥稢 祭 NEXT 
  PCTINCREASE)
* 㬥    ।  ⥫ ⥭⮢ ( 
  ⥭  ।)
* 㢥 ⢮ ப ⠡  ,  㬥訢 ࠬ  PCTFREE
* ᮡ ࠣ஢ ⠡   ⥭


                                   -- 214 --



 ꥤ  ⥭⮢ ⠡ ਬ ᫥ ᫥⥫쭮
⢨:
    1. २ ᭮ ⠡.
    2.   ⠡  ஥묨 ᮮ⢥⢥ ࠬࠬ .
    3.     ⠡  ஢ .
    4.   ⠡.
    5. ᮧ .

       ⥫쭮 襥 ⢮ ⥭⮢

     뢠  ⥫쭮  ।    ᪮쪨 ⥭⠬ 
㬥襭     ᪮७   ࠫ 䨪権.
  ᮡ   砥,   ⠡ 祭 ⥭ᨢ .  
⮬ 砥  ਥ  襥 ⢮ ப   ,
᫥⥫쭮, 㢥稢 饥 ⢮ .  (  ⢮
  㤥 , ⢮ ⥭⮢  ,      - 
ᨬ  ࠬ஢  FIRST, NEXT, PCTINCREASE).

    ⮡ 㬥 ⢮  (  -  ப) , 㯭
⠡, 㢥 祭 ࠬ  PCTFREE   CREATE  TABLE.
 祭 PCTFREE,  ࠢ 95-99,  ᭨ ᫮ ப ⠡ 
  . (  ᮮ⢥⢥ 㬥 祭 ࠬ
PCTUSED).

       ,    ࠧ饭  ப ⠡   ࠪ筮
 設⢠, ᮡ -    ⠡.  筮 讥 祭  PCTFREE
ਢ  䥪⨢ ᯮ짮 . 訥 ⠡ 
ᯮ 室 襥  ⢮ ,  祬    ᭨
䥪⨢ ஢. ஬ ⮣, ࠤ  ᪠஢ ⠡,
⠪  室 ᬮ 襥 ⢮ .

      砩,  ⥫쭮 襥 ⢮ ⥭⮢ - ᫨  
"ࠣ஢"  .   ࠣ஢   ᢮
࠭⢮ 室    뢭 ⪥,  ।  
 ⪮  ࠧ 䠩 .   ⮬ 砥  㦤 㤥
ᯮ짮 讥 ᫮ 쪨 ⥭⮢ ( - ६,  
८࣠樨 ).

     ஬ 砥   ᮢ  㬥襭 ⢠ ப  
(  १ - 㢥祭  ᫠  );   楫 - ⠭
ࠬ஢  ⠪ ࠧ,  ⮡ 㬥訫 ⢮  
⥭,   ᫥⥫쭮 -  㢥稫 ᫮ ⥭⮢.

        । ⥭⮢

 ⠡      , ॡ ।
  ⥭.     ⠡ ⠪   
筮 .    ।  ⥭ ॡ ⥫
ᮢ, ⥫쭮 ᮪ ⢮ ⠪ ।.

⮡ 㬥 ⢮ । ⥭⮢,  ᯮ  
᪮쪨  㪠 ⮤:
    * 㪠 ࠬ INITAL  ᮮ⢥⢨   ࠧ஬ ⠡
    * 㪠 襥 祭  ࠬ NEXT, ⮣ ᫥騥 ⥭
        ࢮ
    * ᯮ 㫥 祭 ࠬ PCTINCREASE, ⮣ 
      ᫥騩 ⥭ 㤥  ।饣.


                                   -- 215 --



       ᮢ  

    ⮭宦 ᮢ         ⥫쭮 
 ந⥫쭮,    ६    ࠢ.   
,   ⢫  ⨢   ,   室
ᯮ    ᪮쪨 ࠧ ᪮ ࠩ.  
ᯠࠫ     ⥭    ꥪ,   ⠪
ࠧ   ࠡ⮩ DBWR.

    ⮯ ⠡  ᮢ   ।   ᮧ 
ꥪ⮢.    CREATE  TABLE  CREATE INDEX  뫠 
ࠧ ⠡ ࠭⢠ (䠩, 室騥   ࠭⢠ 
ᯮ  ࠧ ᪠).

   ⠡筮 ࠭⢠ ⭮ ⠡ 室
ᮧ   㧨    ,  ⥬ 㤠  ⠡ 
    ⠡      ன (२).

  ⠡筮 ࠭⢠     ⬥  
ᮧ   ॡ㥬 ࠭⢥.

          ""  ⠡

"" ।⠢  ᥡ ࠧ    ⠡    
ᯮ  ⥩  ࠧ ன⢠  ࠫ쭮 㯠
᪮쪨 짮⥫.  ਬ,  ⮡ ࠧ 100 ⮢  10 ⥩,
室 த ᫥饥:

1.  ⠡筮 ࠭⢮,  饥   10  䠩,  
    10 ⮢ (   室). 祬 ᮧ 
   䠩  ࠧ ᪠.
2.  ⠡, ᯮ ᫥騥 ࠬ :
    storage(initial 10m next 10m minextents 10 pctincrease 0)
3.  ⠡ 㧨,   ।   䠩, 祬
    室 㦠 ࠧ   .

          /  䠩    ࠢ 䠩

    ⥬ ORACLE    䠩 ணࠬ ᯥ祭 ॡ 
ࠩ   䠩 ,   ࠢ騩     䠩 ୠ ୮
믮.  ⨬쭮 ࠧ饭 䠩   ந⥫쭮 ⥬
 ⥣ ⠭  砥 ਨ ⥫.  ⭮⥫쭮 ࠧ饭
ࠢ 䠩  䠩   ᪠ ᫥饥:
*   ᮯ୨⢠  / 頩 䠩     ࠧ ᪨
* 頩 ᪮쪮  ࠢ 䠩    ࠧ ᪨.

      / 䠩 ୠ

      ᯮ짮 䠩 ୠ ୮ 믮 殮 㦠
/뢮,  ⥫쭮 ४㥬    ᪨ ⫨  ᪮
.    䮭  LGWR ࠡ ࠫ쭮  ⠫쭮
 ⥬.

    ᫥⢨ ⮣,   䠩 ୠ ਧ ন ⢥ত
࠭樨,    ᯥ  .    LGWR ⮫쪮
 ଠ  ୠ,  祬  ᨭ஭.   蠣 



                                   -- 216 --



ᯥ祭 ᪮  㯠  ⮬ 䠩  - ।  ࠧ ᪠ 
䠩 .  䠩 ୠ  室   ᪥, ⠪  LGWR
   ଠ ᫥⥫쭮.

               ⨬ ࠢ ࠬ

    饥 ᠭ  ਬ  ORACLE Version 6.0.26  . ᠭ
 ᨨ 6.0.27   ਢ  "㪮⢥  ன
ந⥫쭮 ".

     묨 䠪ࠬ, 騬  ந⥫쭮,  ࠧ
  SGA  䥪⨢  䮭  DBWR. -  ( -
 ) ᮤন  ⮫쪮    ;  
ᮮ⢥ ஢ .  DBWR ⢥砥  
ଠ樨  ஢  .

   ஢ ஢ ᢥ   믮 commit, 讥
⢮  ஢ ஢  ࠭   ६. 
ঠ ࠫ쭮 ࠡ⪨  筮 ஢,  
   ,   -  ᠭ  .   ࠧ,
ன ࠢ ஬,   㫮  ᮬ DBWR 
⥫쭮   ந⥫쭮.

  짮⥫ 㦤  㯥     믮
ந쭮 SQL - 樨,   । ஢,    ⮣ 
 -.  ६ ⮣ ᪠ ᯮ  奬 ஢  ᫨
室  室  ,    ᪨. ᫨  
⠬  ,    짮⥫   ᪠ ᢮
 ( ᮤঠ騩  ) ᯨ᪥ ஢ LRU.

    ணࠬ    ⥬  ORACLE  ন LRU - ᯨ᮪
஢ (Least Recently Used).   ⮬ ᯨ᪥  㯮冷祭  ᭮
⮣, ᪮쪮    뫮 ᫥ 饭.  設 ᯨ᪠
室 , ᯮ짮訩 ᫥,    ᯨ᪠ -  
  ᯮ짮訩.      ࠭,    
ᯮ㥬   室   襥 ६, 祬  
ᯮ㥬.

  짮⥫ 室 ᢮   (  ,   ᯨ᪥
LRU),   뢠      ⥬ ६頥    設
ᯨ᪠ LRU.

    ᫨   ᯮ  祭 ⥫쭮  ६,   ⥯
    ᯨ᪠ LRU   㤥 "饭" ᮬ DBWR  ⥬
  ଠ樥.  , ᮤঠ騩 ஢ , 
  祭 "᢮",   ᮤন  㤥 ᪮஢ 
 ᮬ DBWR.

      ਭ ஢

     ᫥  ࠡ     ᯮ 
SQL*DBA MONITOR  樥 STATISTICS.   ࠡ⮩   易
᫥ ⨪:
    * 䨧᪨ ⥭
    * 䨧᪠ 
    *  -  ஢

     祭 ⢠ ஢ 

                                   -- 217 --



   ࠬ  䠩 INIT.ORA,      -
DB_BLOCK_BUFFERS.   ࠢ ⢮ ஢  ୮ 㫥 .

稢 祭  32 ᫨誮   設⢠ ॠ .  
ॠ쭮 ᫮  100  200. ᫨      100  ⮢,
室  ᬮ ⠭ ⮣ ࠬ  1000  .   
⥬  VAX/VMS  (  64  ⮢)  䨣    20
⮢.  ⭮ 祭,  ,    ࠡ ਫ  
樮 ⥬.

稢 祭 DB_BLOCK_BUFFERS,  ⠪ 㢥稢:
    * ࠧ  SGA ( )
    * 饥 ⢮ ,   ஢
    * ⭮ ⮣,   ⠭  
    * ᯮ짮 ⨢ 
    * ࠭ 

ந⥫쭮 蠥,   ࠭   ⠭ १.
  㢥祭 ࠧ ୮ 㫠   ⮬,   襭
ᯮ짮  ⠥  ࠭    SGA,  ⠪  
ᮢ 짮⥫.   ன  樮 ⥬ ࠭ 
 㬥  ᪫.

       ७樨  ஢ 

  ⥬  ஢  ஢ ப ந⥫쭮  ᭨-
,  ᫨  짮⥫  ࠧ ப   .  
᪮쪮 ஢  ப  ࠧ ࠭権   ६
室   ,   믮  १ࢨ 
.  ᪮ ॠ쭮 ६  祭 , 蠭  짮⥫
१ࢨ஢      ,      祭
⨢ 㯮 ⠪ 砥.  ⨪  ⬥砥 ﬨ
" -  ".

    ᫨  ⠥,  ⮫   ⨢ ᯮ㥬 ⠡
᭨  ந⥫쭮,   ᭨ ⢮ ப    
  (.    ࠧ  " ⥫쭮 襥 ⢮ ⥭⮢").
⨬  ᭨ ⭮ ⮣,   ࠧ ࠭樨  ६
  ப, ᯮ   .

        ன  DBWR

    饥 ᠭ  ਬ  ORACLE Version 6.0.26  . ᠭ
 ᨨ 6.0.27   ਢ  "㪮⢥  ன
ந⥫쭮 ".

    ᫨ ࠬ DB_BLOCK_BUFFERS 砥 500   ஢, 㬠稢
ࠬ 䠩 INIT.ORA  ᯥ稢 㤮⢮⥫ 䥪⨢.
,  ᫨   ⠭ 祭 ⮣ ࠬ  500, 室
ந ⥬ ⠪ ࠧ, ⮡  㬥 㬬 ࠡ  
DBWR  ᮢ 짮⥫.

   ன DBWR ᫥騥 ࠬ:
    * DB_BLOCK_MAX_MOD_PCT
    * DB_BLOCK_MAX_CLEAN_PCT
    * DB_BLOCK_TIMEOUT_WRITE_PCT
 ࠬ ।⠢  ᥡ 業  DB_BLOCK_BUFFERS


                                   -- 218 --



       ࠡ⠥ DBWR

  ᪠ ᢮   ᯨ᪥ LRU  짮⥫ 뢠
⢮ ய饭 ஢.    ⮫쪮    ய ⢮
஢,  襥  祬  業 DB_BLOCK_MAX_MOD,  ᮮ  ⮬ 
DBWR, ⮡ ᫥ 砫  ஢. 짮⥫᪨  ४
 ᢮ ,  ॡ - ஢ DB_BLOCK_MAX_SCAN_PCT,
᫨  ⮬ 砥    ᢮ , 㤥 㢥祭 祭
᪮  "dbwr free needed",  砥,  짮⥫᪨
 ,  DBWR    ᯮ짮.

      ⠪ ᮡ⨥,   DBWR 稭  ᯨ᮪ LRU
稭  " ࠭  ᯮ짮  ".  ᫨   ᮤন
 ,  DBWR "頥"  ⥬  ଠ樨     ⥬
砥  ᢮.   ⪨ த   ,   㤥
饭 業 , ࠢ DB_BLOCK_MAX_CLEAN_PCT.

     ,    㦥,  DBWR ਮ᪨ 믠
(    "timeout")    頥  ⮫쪮  , ᪮쪮 㪠 
DB_BLOCK_TIMEOUT_WRITE_PCT. ᫨ ⥬   쭮 , DBWR
ਮ᪨ 頥   .

 ࠧ,  DBWR 㢥   :
*   짮⥫ ⠫  祬 DB_BLOCK_MAX_MOD_PCT ஢ 
  ᪠ ᢮
* ਮ᪨,  ६ ⠩⮢.

      ਭ DBWR

 ᫥ ࠡ   DBWR  ᯮ   MONITOR
STATISTICS  ⨫  SQL*DBA.      ᫥ ⨪
 ஢:  ( ᠭ   ਫ )
    * DBWR buffers scanned
    * DBWR free low
    * DBWR free needed
    * DBWR timeouts
    * free buffer inspected
    * free buffer waits

ᯮ  MONITOR LATCH  ᫥ ᫥騥 饫 (஢
 ஢):
    * cache buffer chains
    * cache buffers LRU chain

   ᫥  饫  ᫮  ⮫ TIMEOUTS   
.

       ࠡ DBWR

 쭮 砥 DBWR  ᯥ稢 筮 ⢮ ᢮
஢ ⠪, ⮡  ࠭稢 ⥭   .

᫨ DBWR  ࠡ⠥ 筮 ⪮, ⥬ 㤥  墠 ᢮
஢,  짮⥫    ᢮. ⨪  DBWR free
needed 뢠,  ᪮쪮 ࠧ  ⥬ 砫 墠⪠ ᢮ ஢.
 祭   ᢥ  .



                                   -- 219 --



᫨ DBWR ࠡ⠥  ᫨誮 ⨢,   㤥 뢠   
,    ᭮   襬 饬 , ᫥⥫쭮,
  ॡ.  ⮬ 砥 짮⥫᪨   ,
 DBWR     ⥫ ⨪ free buffer waits.

   ⪨ DBWR 訢  ᢮ ஢ ஢  ⥩
ᯨ᪠ LRU.  ஢ 㤥 ஢  짮⥫᪨ ᠬ
 砥,  DBWR ᫨誮 ⨢. ,  ⢮ ஢,   
     ᬮ, 㤥 ᭨  㬠. ࠬ 䠩
INIT.ORA DB_BLOCK_MAX_CLEAN_PCT । ᨬ쭮  ⢮  ஢,
 㤥  DBWR;  ⢨⥫쭮 ⢮ 뢠  
⨪ DBWR buffers scanned.

᫨   ᮤন  ஢ ,  짮⥫
  襥 ६   ᢮.  ⢮ ᬮ७
 ᪥ ஢     - ஢.  ᨬ쭮
⢮ ஢,  짮⥫᪨  㤥 ᬠਢ  
᪠ ᢮, ⠭  䠩 INIT.ORA ࠬ஬ DB_BLOCK_
MAX_SCAN_PCT; ⢨⥫쭮 ⢮  ᪠஢ ஢ ⬥砥 
ࠬ ⨪ free buffers inspected.

襭 ࠬ DB_BLOCK_MAX_MOD_PCT 㤥 ᭨ ⥫ ⨪
free buffers inspected,   ६   㢥祭 -  ࠬ DBWR
buffers scanned.  ᫥⢨ ⮣,  ⥫쭮  訬    
⥫,   ஡ ᪮쪮  祭  ࠬ
DB_BLOCK_MAX_MOD_PCT   ⨬쭮 祭.

    祭 ⥫ DBWR free needed    free  buffer  waits ᥣ 
 㫥묨.  ᫨   ⠪,  室 㢥 祭 ࠬ
DB_BLOCK_MAX_CLEAN_PCT.

        ன ୠ ୮ 믮

ୠ ୮ 믮 ᮤন 䨪樨   . ᫨ ᫠
樮 ⥬  ⪠ ᪨,  ଠ ୠ ᯮ 
⠭     , 믮   ।饩 ஫쭮
窨.

         ,   ୠ ୮ 믮 室
 SGA.  ࠧ,   짮⥫    ୮ 㫥
,  뢠    ୠ ୮ 믮.  
ୠ ࣠  ᫥⥫쭮 ਭ樯.   ࠭ 
,   ࠭ ⮫쪮 ஢ .   ⪥ 
짮⥫ ஢    ୠ   稭  ⮣
,  ஬ 稫 ।騩 짮⥫. ⮡ ந襫 commit
筮,  ⮡   뫨 ᠭ ,  짮⥫  
 ୠ.

  LGWR 㢥  ᫥ ᮡ:
    *  ॡ commit
    *   LGWR 室   ஢
    *    ୠ

    ᫥ 㢥 LGWR 뢠   ஢  ୠ 
 ( ⢥ত,   ⢥ত).  commit  ᪮쪨
짮⥫   믮     /뢮.  ࠧ
। ࠬ஬  䠩 INIT.ORA LOG_IO_SIZE.


                                   -- 220 --



      権 commit 㤥 易  (뢠 - "樥
஢"),  ⥬  ந⥫쭮. 樥 ஢ - 
। ⢮ ࠭権   ;   ᫥騬
⭮襭:
            (user commits/small redo writes) = transactions/write

      ⪮ 饭 ᯮᮡ ⨬樨 ୠ

* 頩 online - 䠩 ୠ  "" ன⢠
* ࠧ頩  ᪠,  ᮤঠ 䠩 
* 㢥 祭 ࠬ LOG_BUFFER  ᭨ /
* 㬥  ஫ 祪 㢥稢 ࠬ LOG_CHECKPOINT_INTERVAL
* 㬥  । ୠ,  㢥稢 祭 ࠬ
  LOG_ALLOCATION&

      ਭ ୠ ୮ 믮

     ᫥ ࠡ ୠ  ୮  믮  ᯮ
 MONITOR STATISTICS ⨫ SQL*DBA.  ᭠ ⨪
ୠ ᫥:
    * DBWR checkpoints   (஫ 窨)
    * chunk allocations  ("訥" ।)
    * small redo writes  (   ୠ)
    * large redo writes  (訥   ୠ)

      ⨬  ୠ

    ࠬ LOG_BUFFER 䠩 INIT.ORA । ࠧ (  ) ஢
ୠ,  室  SGA. 祭 ⮣ 祭 ᭨ ⨢ /
 ୠ  ᮡ -   讬 ⢥  ࠭権.

        ஫ 祪

    ஫ 窨    ਮ᪨ ᭨ ந⥫쭮 .
  ᫥ ⮣,  㤥 ᠭ ।   ᫮   
ୠ  (㪠뢠  ࠬ஬  䠩 INIT.ORA LOG_CHECKPOINT_INTERVAL) 
᫥     ⨢ 䠩 ୠ ( ४祭 ୠ).

 ६  믮 ஫쭮 窨 DBWR ࠭,     ,
     ।饩  ஫쭮 窨, ᠭ  .
࠭஢ ⮣,      ᠭ   ᮢᥬ 
砥,        ᠭ ࠧ  讥 ᫮ ஢.
⥭樠쭮 ᮪ 㬬ୠ 㧪 DBWR  맢  ७-
  ⥬  ⮬ ⥫쭮 ᢥ ⢮ ஫ 祪 
.

 ६  ஫묨 窠    ᫥騬 ᯮᮡ:

*  䠩 ୠ  10 ⮢  
* ⠭    ࠬ  LOG_CHECKPOINT_INTERVAL   祭 讥 祭
  (ਬ - 500000) ⮡ ࠭஢  ஫ 祪
  ⮫쪮 ᫥     䠩 ୠ.

稢 祭  ࠬ LOG_CHECKPOINT_INTERVAL 筮 , ⠪
  ࠡ   䠩 ୠ  ᪮쪮 ஫ 祪.




                                   -- 221 --



஫쭠 窠  믮   ४祭 䠩  ࢠ  
㢥祭  㢥祭 ࠧ஢  ᠬ 䠩.   ᨫ쭮 㦥 ⥬
䠩 ୠ  5-10 ⮢  墠   ᪮쪮  ࠡ
 ஫묨 窠.   筮    ஫ 祪
  ⨢ ⥬.

砭: 祭  ६  ஫묨 窠 ᮮ⢥⢥
           㢥稢 ६ ⠭ ᫥ ਨ.

    ⢮ ஫ 祪, 믮   ,
ᮤন  ࠬ ⨪ dbwr checkpoints.

        । ୠ

। ୠ    ,     ॡ
⥫쭮     ୠ.

 ⥬  ⢥ ஬  室 । ୠ
 ࠬ   ⮬  砥  室 ⠭ 祭 ࠬ
LOG_ALLOCATION  祭,  ࠢ 襬 襬 䠩 ୠ.  (
砥 㢥祭 㬠稢 祭, ஥ । 
᪮쪨 ।   䠩).  ⠭ 讣 祭
࠭ ⢥  ।  䠩 ୠ  ᭨ 
 । ୠ (筮  ண)   
䠩 ( ஫ ).

    ⢮ ॠ쭮  । ୠ  ᬮ 
ࠬ ⨪ chunk allocations.

騥 ᪨ ⥬  ᯮ짮 祭 ࠬ
LOG_ALLOCATIONS,  ஥ ࠦ ⢮ ஢  ࠧ 䠩
ୠ.     ଠ樨  ⠭ ⮣ ࠬ  
 21.

          ࠬࠬ  ⨪

 ᫥饩 ⠡ 頥    祭ﬨ  ࠬ஢ ⨪ 
ࠬࠬ 䠩 INIT.ORA  ⥬ ORACLE Version 6.0.26  ࠭.  
ᨨ 6.0.27   -    "㪮  ன
ந⥫쭮 ORACLE RDBMS".

  ⨪           ⥫쭮 ...     㥬 ⢨

chunk allocations          ᭨     LOG_ALLOCATION
buffer busy waits                      ᫮ ᥣ⮢ ⪠ /
                                      㬥 ⠡, ⮡ ப -
                                      頫  .
DBWR buffers scanned       ᭨    
                                      DB_BLOCK_MAX_CLEAN_PCT /
                                      DB_BLOCK_TIMEOUT_WRITE_PCT
DBWR checkpoints           ᭨    
                                      LOG_CHECKPOINT_INTERVAL / 㢥
                                      ࠧ 䠩 ୠ ୮
                                      믮.
DBWR free low              ᭨    
                                      LOG_CHECKPOINT_INTERVAL
                                      / 㢥
                                      DB_BLOCK_MAX_CLEAN_PCT

                                   -- 222 --



DBWR free needed           ᭨    
                                      DB_BLOCK_MAX_SCAN_PCT /
                                      㢥
                                      DB_BLOCK_MAX_CLEAN_PCT
DBWR timeouts              ᭨    
                                      DB_BLOCK_MAX_MOD_PCT
free buffers inspected     ᭨    
                                      DB_BLOCK_MAX_CLEAN_PCT / 㢥
                                      DB_BLOCK_TIMEOUT_WRITE_PCT
free buffer requested      ᭨     DB_BLOCK_BUFFERS / 
                                      ਫ ⠪, ⮡ ᤥ 
                                      䥪⨢ ᯮ짮 .

free buffer scans                      DB_BLOCK_BUFFERS
                                      / 㢥
                                      DB_BLOCK_MAX_CLEAN_PCT
                                      / 㢥
                                      DB_BLOCK_TIMEOUT_WRITE_PCT
free buffer waits          ᭨     DB_BLOCK_BUFFERS
                                      / 㢥
                                      DB_BLOCK_MAX_CLEAN_PCT
                                      / 㢥
                                      DB_BLOCK_TIMEOUT_WRITE_PCT
                                      /  ਮ
                                       DBWR
physical reads             ᭨     DB_BLOCK_BUFFERS
physical writes            ᭨     DB_BLOCK_BUFFERS
(User commits/small redo writes)
                           ᭨     LOG_BUFFER /
                                      㢥 LOG_IO_SIZE

cache buffer handles    ᭨ -   
cache buffer chains     ᫮   DB_BLOCK_MAX_CLEAN_PCT
cache buffers LRU chain               / 㬥
                                      DB_BLOCK_TIMEOUT_WRITE_PCT

        ன ᥣ⮢ ⪠

     ⪠ ᮤঠ ଠ,  室   ⪠  ᠭ
࠭権.  । ⥬  짮⥫᪨    ,  
뢠    ଠ   ⮩ 䨪樨  ᥣ ⪠.
⢥騩    ࠧ 䨪 ᨬ  ⮣,
ᠭ   ࠭,   ᫨ ࠭ 㤥 ⬥ ( 
 뤠祩  rollback),  ଠ  ᥣ  ⪠  㤥
ᯮ짮  ⠭    ﭨ, ।饥 
࠭樨.

    直 ࠧ   짮⥫᪮   ࠡ  
࠭ﬨ 砥 ᥣ ⪠.   殮  ᥩ ࠭樨
짮⥫᪨      ଠ  ⮫쪮   ᥣ.

     ࠭ 뢠, ଠ ⪠ ᢮,    
㭨⮦;   ⠥  ᥣ ⪠  ᯮ짮 ࠫ묨
ᠬ.  ⪠ 뢠 ᫥⥫쭮    ⥬  㤥
(᫥ ) த  砫 ᥣ ⠪, ⮡ ࠭஢, 
ଠ ⪠ ࠭ ⠪ ,   .



                                   -- 223 --



    ᫨ ࠭ ⮫쪮 ,     ᥣ ⪠  
ᠭ묨 묨,   ।   ᥣ ⪠, 塞 
ࢮ.

    ᭮묨 ࠬࠬ 䠩 INIT.ORA, ᯮ㥬묨  ன ᥣ⮢
⪠, :
    * ROLLBACK_SEGMENTS
    * TRANSACTIONS_PER_ROLLBACK_SEGMENT

      ਭ ᥣ⮢ ⪠

    ⮡ ᬮ ⥪饥  ﭨ  ᥣ⮢  ⪠,   
  DBA_ROLLBACK_SEGS.    ⪠   "INUSE" (ᯮ)
 "AVAILABLE"  (㯭).  ஬  ⮣,  ᬮ  ⨪ ᥣ⮢
⪠  ᯮ짮  MONITOR ROLLBACK.

      ᮢ ⥭

 ᮣᮢ ⥭ ࠭,   १   
  뤠  ४묨.  짮⥫᪨ , 믮騩
  ,  訢  ப, ஢ 㣨
짮⥫ 㦥 ᫥ 砫 ࠡ⪨ .   ⮬ 砥 
ᯮ ଠ  ⪠,  易  室 ப,  ⮡
⠭ ﭨ      ᪠  .  ᫨ ப ᯥ
   ࠧ,  믮 ᪮쪮 権 
४஢   楫    室 ﭨ.

砭:   ⢨  ४樨 ப 믮  筮 ६
            짮⥫.   ࠧ,   ᨬ 
           ᫥⥫쭮 㯠,  ⢮ ᪮쪮
           ᮣᮢ  ⥭ ᨩ  ப.

      ᯮ짮 ᪮쪨 ᥣ⮢ ⪠

 ࠭  ଠ  ᥣ ⪠,    
⮣ ᥣ  ६ ।⢥ .   饬 砥  -
樨 ந室 祭 , ⠪     ⪨ ப.

     ᫨    ⢮  ࠫ  ࠭権, 
७  짮⥫ ࠨ  ।   ᥣ.
 ⨪ header units/sec  ⮡ࠦ  MONITOR ROLLBACK
뢠 ᪮쪮    .  訩 室   ⠪
樨  -  ᮧ   ᯮ짮   ᥣ ⪠.

     १ ⮣,   ᥣ ⪠ 뢠  ஬  
,  ࠭樨, 室騥  ⮣ , । 
ᥣ⠬ ⪠,  易   ஬. ⥫쭮, 
   ᥣ ⪠ ᭨ ᮯ୨⢮.

     ⪠ SYSTEM ᮧ  㬮砭  ६  ᮧ .  
  䮭  ᯮ   㦥 楫.   16 ᠭ, 
ᮧ  ᥣ ⪠.

     ⪠  ᯮ  ⠪       ⠪
ࠧ, ⮡ ᯮᮡ⢮  㧪  䥪⨢ ࠡ. ਬ -
ᥣ   ᯮ  ᯥ樠쭮 ᪥    ࠧ,
ᯥ樠쭮 ᯮᮡ  । ࠡ   ஬
ORACLE.

                                   -- 224 --



      롮 ࠧ ᥣ⮢ ⪠

    訥 ᥣ ᪮॥ ᥣ  ஢ (室 
⨢ )  ⥫쭮 ६.  㣮 ஭ -  訥
ᥣ ⪠ ।⥫쭥  ࠡ ࠫ ᮢ.  
ࠡ騥 ࠫ   ᮧ ᮣᮢ    
㦤  祭 ன ଠ樨 ⪠.   প ⠪ ᮢ 
ਤ 㢥 ࠧ ᥣ⮢ ⪠.

    ᫨ ⨢   ᥣ ⪠  ६ 
᪮쪮  ࠭権,  ⥬ ORACLE ⠥    ࠢ୮
।   ᥣ⠬.

    ᫨ ᥣ ⪠  ࠧ,     
稭  稭 ୮ ᯮ짮 ਬ୮   ६.  ᫨ 
  ᥣ⮢   ⠫,     ࠭ 㣨  筥 ४뢠
  ଠ ( ᫨ ⠫ ᥣ   ).  
ࠫ  ࠭稢  ࠧࠬ 쭮 ᥣ ⪠,
४    ࠧ.

      ஢ ᥣ⮢ ⪠

    筮  ,   ᥣ⮢ ⪠ ᯮ  ᪥ 
୮ 㫥      ࠢ  ஬ ஢   奬  LRU.
᫨ ᥣ ⪠ 筮     筮 , 
⭮  ஢.  蠥 ந⥫쭮  ⥬  訬
⢮ ⪨ ᮢ.

    ⥫쭮, ᥣ ⪠    筮  ,    
 筮   ᯥ祭 ᮣᮢ ⥭.

                ਭ ᯮ짮 譥 

        롮 ࠧ㬭 権 ⮪஢

    ᫨  稫  ⮪஢,   室
  ந⥫쭮,  ⠪   . ᫥ ⮣    ࠬ
AUDIT_TRAIL 뫮 祭 ⮪஢,  짮⥫  ᬮ 訢
 ଠ 뤠 ᮮ⢥騥 SQL - .   
⮪஢ 祭 ,  ଠ   쭮
, DBA  ஢ 짮⥫ ⥫쭮   ⭮
 樨  ᡮ 饩  ଠ樨.

         ஡

᫨  ।,    ⥬  㧪  ,   
᫥騬:
    * ࠭祭 CPU
    * ࠭祭 饫
    * ࠭祭 DBWR
    * ࠭祭 LGWR
    * ࠭祭 /뢮

 ⥬  "࠭稢" ᮬ (⠪  DBWR  /), ᫨ 
   ࠭稢  ந⥫쭮   ᫨  㢥祭
⮣    ந⥫쭮. 㣨 ᫮ -  ⨣
᢮ ।    믮  ॥  ⥫ ࠡ, 
᫥⥫쭮 - ࠭稢   ⥬.

                                   -- 225 --



      ࠭祭 CPU

    ᪨ - ᨬ ய᪭ ᯮᮡ ⥬ ORACLE Version 6
⨣ - ࠭祭   魮  .  ⮡ ।,  
ࠡ ⥬ ࠭稢 CPU, 室 ᯥ樠 ᪨
ࠡ  (    ⭮ 樮 ⥬).

    ᫨ ⥬  ࠭稢  CPU,     ⥫ 業
୮ ६ 筮 אַ ॢ頥   ⥫ ய᪭
ᯮᮡ.

      ࠭祭 饫

    ⥬   ࠭祭 饫,  ᫨    ᫮ ⠩⮢.
饫 -  堭 ஢  ஢, ਬ塞  ࣠樨
᫥⥫쭮 㯠    ࠬ   SGA.  饫  
祭 ⪮ ६  ।⠢ ⥮᪨ ᨬ  ய᪭
ᯮᮡ  ⥬.   ᫥  饫  ᯮ  
MONITOR LATCHES ⨫ SQL*DBA,      
樮 ⥬      䨫᪨ ⢨.   
஡ ଠ樥   "㪮  짮⥫   ⠫樨".

      ࠭祭 DBWR

஡  䮭 ᮬ DBWR ,  ᫨ ⥬   믮
室 /뢮. ⮡ ᬮ,    ⠪ ,
ᬮ  뤠     MONITOR STATISTICS. ᫨  ⢨⥫쭮 ⠪,
ᯮ ᠭ묨  ﬨ ன  DBWR.

      ࠭祭 LGWR

    ⮡ ஢,      ஡    ୠ ୮
믮,  ⨢ /  ன⢥, ᮤঠ饬  䠩.
  ⨢ / ⭮⥫쭮 ⨢ ࠭権,   ᫮
࠭権   ॢ  ᫮ 権 /, ஥   믮
ᨭ஭.  ⮩ 窥 / 筥 ,  ᫮ ࠭権 㤥 
 㢥祭 樥  (࠭樨  䨧 ).

      ࠭祭 /

⥬  ࠭稢 /뢮  ६ ࠧ 稭:
* /  䠩  ୠ  ୮ 믮 ⠭ 㧪 ⮬, ᫨
  㬬୮ ⢮         ६ ॢ蠥
  ய᪭ ᯮᮡ ᪠.
*  ⮬ ⠭ ⥭  , ᫨ ⢮ ࠭,
  ॡ㥬  । ᪠  ஫, ॢ- 蠥 
  ⮣ ன⢠.
*    ⠭ 㧪 ⮬, ᫨ 䮭  DBWR  
    訥  .

      21     ,  

     ⮩  ᬠਢ , 易  ஢ 
, ࠧ塞  ᪮쪨 ࠬ  ᪮쪨 ࠬ
ଠ  ⮩    ।,   㦤 ࠧ
  饩    ᪮쪨 ࠬ.

          - ⥬, ࠧ ᪨

                                   -- 226 --



      ⥬  ६  ᪮쪮  ஢,  
뢠 ⥬, ࠧ饩 ᪨. 筮  ⥬,   ன
    ࠧ  ஢, ࠧ  ࠩ
(ﭨ  㭪   1).

        ᯮ짮 SQL*DBA  ᪮쪨  ORACLE

    ଠ쭮   ⨫ 頥  㬠稢 , ࠡ饬
 ᭮ 設.  ᫨  ࠡ⠥ SQL*Net,     
ᮥ  㣨 ࠬ,  ᯮ짮  SET INSTANCE
(. ਫ ).

         뫠      ᮡ⢥   䠩 INIT.ORA, 
஬ 㪠뢠     (騥) ࠢ騥 䠩.  ࠧ,
INIT.ORA - ࠧ塞 䠩,    ६  ࠢ騥 - ࠧ塞.

       ⥬  樥 SHARED

 ⥬, ࠧ ᪨ (ਬ - VAXCLusters)   
஢   ० SHARED  ⮢   樥 SHARED:

    SQLDBA> STARTUP SHARED

    ᫨   饭,   㬮砭 ਭ  EXCLUSIVE.  ᫨
-  饭  樨 SHARED,   㣮  ᬮ
   .
    ᫨      樥 SHARED,  㣮 ,
뢠騩 , ⠪  ᯮ짮  .

        ࠬ INIT.ORA  ⥬, ࠧ ᪨

 ⠪ ⥬ ⭮ ࠬ  䨪ᮬ "GC":
    * GC_DB_LOCKS
    * GC_ROLLBACK_LOCKS
    * GC_ROLLBACK_SEGMENTS
    * GC_SAVE_ROLLBACK_LOCKS
    * GC_SEGMENTS
    * GC_SORT_LOCKS
    * GC_TABLESPACES


   䨪 "GC" 砥 "Global Cache".   祭 । 
 ஢,      ஢. 祭 
ࠬ஢   ᯮ짮 । ᮢ 樮
⥬.

     ⥫쭮 ଠ樥  ⨬ ࠬࠬ   ਫ D
 "㪮 짮⥫  ⠫樨"   襩 樮 ⥬.

 ⥫ ࠬ,  易  ࠧ ᪮:
    * INSTANCES
    * LOG_ALLOCATION

        ᯮ짮 ᥣ⮢ ⪠





                                   -- 227 --



 ⪠  ஬ SYSTEM   ⤥묨   ;
  ࠧ ࠬ.  ⪠   ᮧ DBA 
    ந쭮 ⠡筮 ࠭⢥.    
 㯠   -   筮  饬 ᥣ ⪠,   
 ⮢.

 짮⥫ ࠧ筮,  ࠡ⠥     묨   騬 (PUBLIC)
ᥣ⠬ ⪠.

       ᥣ ⪠

 ⮣, ⮡ ।  ᥣ  ⢥ 
ORACLE, DBA :

1.    SQL -  CREATE ROLLBACK SEGMENT ᮧ ᥣ ⪠.
2.     ⮣ ᥣ  ⢥ 祭 ࠬ ROLLBACK_SEGMENTS
   䠩 INIT.ORA;  ⨬  ९  ᥣ   ஬.
3.  砫 ࠡ   ⨬  ᥣ⮬  室 ⠭ 
    ⮢ .

      騥 ᥣ ⪠

    騥 ᥣ (PUBLIC)  ᮧ  ஬  ⠭
㯭묨    ᮧ.  ᯮ㥬    騥
ᥣ   "१ࢨ஢"   ஬     ࠭ 
  ⠭ (shut down).  ᫥ ⠭ ᢮ 騥 ᥣ
 १ࢨ஢  㣨 ஬. 筮 騥 ᥣ 
㪠뢠  䠩 INIT.ORA.

                ஢  ⠭ ⥬, ࠧ ᪨

              ᯮ짮 ୠ ୮ 믮

ᨬ  ⮣,  ᪮쪮 ஢ ࠧ  ,  ᯮ
 ୠ ୮ 믮.  ᫨ ᪮쪮 ஢ ࠧ ,
 ࠧ  ⥪騩 ⨢ 䠩 ୠ.  騥  
           online 䠩 ୠ ୮ 믮.
᫨   ஢ 뢠   䠩 ୠ,    
稭   㣮 䠩.

      । ࠬ   ୠ

 ⥬, ࠧ ᪨    ।  
 ⥪饣 䠩 ୠ.     䥪⨢ ᯮ짮
䠩 ୠ.   뢠 "।ﬨ",     ࠧ
㪠뢠    ࠬ LOG_ALLOCATION 㠫쭮   .
᫨ । ,    ந  । 
⥪饬  ᫥饬 䠩 ୠ.

  䠩  ୠ  ୮ 믮     -
ࠢ 㬬 祭 LOG_ALLOCATION   ࠧ  ஢.  
࠭,    ६  ࠡ     ᬮ
।    online - 䠩 ୠ,     ⮬ ⥫
४祭.  ਬ  - ᫨       ॡ 
 䠩 ୠ (⠪ 㪠   LOG_ALLOCATION),    
쥣  室 㤥 ४ 䠩 ୠ,    
      ୠ.


                                   -- 228 --



᪮쪮 ४権   । 䠩 ୠ:
    * 㪠뢠    ࠬ  LOG_ALLOCATION   - 1000 
    * ।  䠩 ୠ ࠧ஬ 2000 , -  
      ᫮ ஢
    * ᫨ ,  室   -  ।  
      .

襭 ।塞  ᪮쪮  蠥    ᯮ짮, ⠪
    ⠥   ᯮ짮    ४祭 
 䠩  㣮.

      ஫ 窨

    ஫ 窨 믮 ⭮⥫쭮 ஢.  㣨 ᫮ -
஫쭠 窠  믮       ᫥ ᮡ⨩:
*   ⢮ ᠭ  ୠ   । 
  ⨣ 祭,      ࠬ஬ LOG_CHECKPOINT_INTERVAL
*   뢠 ⥪騩 䠩 ୠ ୮ 믮-  ( 
  ४祭 ୠ)

, 騥  䠩 ୠ,   ࠧ ࢠ 
஫ 祪;  ᫥  믮   ⨦  ஬
ண ᫠ ᥩ, 祬 -   ஢  ᨬ 
⮣,     樠஬.

     祭 ० ୠ

     ᯮ짮 ୠ (ARCHIVELOG  NOARCHIVELOG) ⠭
 ᮧ     ᫥⢨   ALTER DATABASE.
 ࠪ⨪ ⭮  ᥩ ,    ⭮  ,
⠪ ࠧ,  ⢥⢥  娢樨 䠩 ୠ  
   ᮡ.    ᯮ짮  ०
ୠ  ⮯ 娢.

      娢

娢 믮   ஢.  娢   믮
 ஬     ⮬᪮, ⠪  筮.  
易⥫쭮  ⮤  娢樨  ᯮ짮 ᥬ ࠬ. ᫨
᪮쪮 ஢  ⮬᪮ 娢樥,   
믮   ,      㢥  室
娢樨.  娢 㤥  筮, ⮫쪮   
ᯮ  ⮤.

  । ᯮᮡ,   , 騩 訩 
 ⠬, 믮 ⮬᪮ 娢஢,   ६   ⠫ -
筮.  ᫨ , 믮 ⮬ 娢 - ⠭, 
᫥ 䠩 ୠ ,    ୠ த   
  ⠭  믮 娢樨.

      ⠭ 

 ⥬  ࠧ   ⠭      
믮 ⮬᪨,  ⠪  ࠧ  न.  ᫨
  ࠡ⠢ ஢ 稫  ਩,      ⠢  
⮬ 㢥  믮 ⠭.   㢥  믮
⠭    ࠡᯮᮡ . ⠭ 
砥  ᥡ  .

                                   -- 229 --



  ,    訫 ਩  稭,  
ᯮ 㣨 ࠬ.   ⮬ 砥 ஢ 訡
 DBA;    ᫥ ⠭     믮
⠭.

      22         

     ⮩  뢠 ᯥ樠 ⥬,  易  । 
 ᪮쪨 ࠬ  ᪮쪨   ਪ묨 ⥬,
ࠡ騬  .  砥  ᥡ:
    * । ନ    楯樨
    * 䨪 ⮢ । ⥬
    * ᯥ祭 楫⭮   

    ଠ ⮩     ਠ,   
  㣮 㬥樨 Oracle Corporation,  ᮡ -  SQL*Net
(ਬ - 騥 㪮⢠  SQL*Net, ᠭ    ⮪
裡,      ⠪   "㪮⢠ 짮⥫  ⠫樨").

         ⠪ SQL*Star ?

   ORACLE  ᯮ짮  䨣樨 ணࠬ த⮢,
   SQL*Star.  SQL*Star -  易  
ணࠬ த⮢, ।祭  প । ࠡ⪨
  ।   . 筮  砥  ᥡ ᫥騥
:
    ORACLE RDBMS   த ।⢥ 砥  ᥡ 㭪樮
                    ঠ ।  ( ਬ -
                  প । ᮢ), ᨬ 
                  ᯮ  ⮭.  楯樨 ஡ -
                  㦤   .

    SQL*Connect    த 㦨 - ""  㣨 ⥬
                  (ਬ - SQL/DS  DB2).  த  
                  ।⢠ ORACLE 㭪樮஢  㣨 ,  ᫨
                    뫨  ORACLE. SQL*Connect   SQL*Net 
                  ࠡ  㤠묨  .

    SQL*Net        த  ண ⥢ 䥩ᮬ
                  SQL*Star.    뫠  
                  ᮮ⢥⢨  ⮪ 裡  ࠧ묨 
                  .

 ⠫ ᠭ  த⮢    㯮⮩ 㬥樨
 SQL*Net  SQL*Connect.  ᭮ ࠢ  ⮩  -
 DBA  ᮯ஢  쭮 , 饩  SQL*Star.

         ⠪ "। ࠡ⪠" ?

। ࠡ⪠          砥,    ਪ
।⢮, ࠡ饥   , 頥   㣮
.  २⢠  । ࠡ⪨   ᫥饬:

*     ᯮ짮    室饥  ணࠬ ᯥ祭.
ਬ  -  ᮭ   ᯮ짮  ன  襢
ࠡ⪨ ,   ६  -   /뢮 
襢, ࠪ᪨ ࠭祭 ᪮   ,      㦨
業ࠫ ࠭饬 .

                                   -- 230 --



*  ⭮⥫쭮 訬 ⠬  㤮   㦨
襥  ⢮ 짮⥫.    ࠡ⪨  믮
 ᮭ     魮       ᯮ짮 PC
 让 業ࠫ쭮 .

*  ࠡ⪠   ⤥,  ⠪   ᥩ ⥬  楫.
塞   ஢ DBA,     ६   ਪ
ணࠬ  㬥⠫ ।⢠  ஫஢ 묨
짮⥫ﬨ.

         ⠪ "।  " ?

।   -    ,  ࠧ饭    祬 
 (設) ⠪ ࠧ,   짮⥫ ਭ   
  ( 䠪᪨  ⮨  ᪮쪨 "" .  
쭠  㠫쭮 ࠢ   ᢮   ஬
(ᮯ஢, , १ࢭ ஢  ⠪ ).

 ,     ࠡ⠥ ணࠬ ᯥ祭 
㯠  㣨 ;   業ࠫ쭮 ணࠬ ᯥ祭,
न饣 ࠡ  .  ᯥ稢  ⮭  
  ⥭樠쭮 ਨ 業ࠫ쭮 窨 (ࠢ饣 ᥬ
).

। ⥬ 砥  ᥡ । ,  ⠪ 㬥-
⠫ ।⢠  ਪ  ணࠬ,    室 
⤥ .   ᪮쪮 ⫨砥   । ,
⠪   । ⥬ ਪ  ணࠬ  室  
 ᯮ  ࠧ 設.   ⮬ 砥    㯠    
ॡ ⥢ ।⢠.

        २⢠ । ࠡ⪨ ORACLE

   騬 २⢠  ,  ।⠢塞 ।묨
  । ࠡ⪮,  ᮢ⭮ ᯮ짮  ORACLE  SQL*Net
 ⥫쭮   : ஧筮 ᯮ  ⭠
⮭.

      ஧筮 ᯮ

 ।   ࠧ  ᪮쪨 "⠬" ( ).
짮⥫  ᮢ ⮭宦 ⠡  ᫥騬 
稭:

*      ࠧ  ᪮쪨  (ਬ - LONDON  BOSTON)
   짮⥫  ⠡  EMP     LONDON,   BOSTON.

*   ᯮ  ⢥ 㧫 ।  
  짮⥫    㧥  㯠  ⠡.

 ஡ 蠥 ஧筮 ᯮ;    -
  ꥪ⠬  (⠡栬  ࠬ)  ᨬ   ⮯.
     ᯮ , ॡ ⮫쪮 
ࠢ쭮  ꥪ.





                                   -- 231 --



   ⮬ -     SQL -     ,
ᯮ  ࠧ 㧫. ORACLE  SQL*Net ᫨  室,
⮬᪨  ஧筮 ⨧ SQL -  (ࠧ)  ࠧ
㤠 㧫.

२⢠ ஧筮 ᯮ   ᥡ:
    *   室 ,  室 
    * ꥪ   ६饭,  뢠  ﭨ
       짮⥫  ਫ.

,  ஧筮 ᯮ -   ࠪ⨪ ।
 ,   ᮢᥬ  易⥫쭮 - । ࠡ⪨.   - 
।      ⠡   ,   
ᮤন  ⠡.   ,  । ࠡ⪥    
 ⥢   ।   㪠 㧫.

      ⭠ ⮭

⭠ ⮭ 砥,   , 室  ।,
 ᨬ  ࠧ쭮  㣨, ᫨ ⮫쪮   ⥢
.

२⢠ ⭮ ⮭   ᫥饬:
*    訡
*   㯭,  㯭 ᮡ⢥   
*    , ⪠ ண ਢ  ⠭ ᥩ ࠡ
*   த ࠡ ᫥ ⠭ 
* ⠭  訡 믮 ᨬ   ⤥쭮 㧫
* 쭮 ࠢ
* ᫮  ᢮   ⤥쭮 
* ᨬ 騢 ணࠬ ᯥ祭   㧫
* -    ⮫쪮     㦤  ஢થ ⮫쪮  
*  ⢥⢥ ஢     .

 ।    ORACLE ⤥    ਭ樯
"ࠢ  ࠢ";     ⭮襭     ࠢ 
易.

⢥ ᪫祭  ᮢ 㧥, ਬ - PC, ᮤঠ
騩 , ਪ ணࠬ  ..    ᮭ쭮   
    ⮫쪮   짮⥫, PC     ᬠਢ
⭮ 訬   ࠬ.

                 ⮢  ࢥ஢

        ।  ⮨  ⮢  ࢥ஢.

 -  ਪ ணࠬ,  㦤   㣮 㧫.  
 㧫,  ᮤঠ騬    ⮫쪮  ਪ ணࠬ,    ணࠬ
  .  ⠬   ᮭ ,  
訥 .

ࢥ -  㧥   ,    襭. ࢥ 
 짮⥫᪨ 樮묨 ⥬  짮⥫᪮
⥬ ORACLE.    ६  ᪮쪮 ࠭権;   
࠭   㯠 ⮬,  㣨 - ࢥ஬.

       ⮢  ࢥ஢

                                   -- 232 --



। ⥬ 㦤  ।⥫쭮  ।   裡
  ﬨ. ।⥫쭮 । 裡 뢠 "묨 ﬨ"
(DBLINKS).   ஡   뢠 .

ਬ - ᫨  ᮥ  -, ⠥  ⠡ Table-M
 - ।,    ⠡  ᠬ  室  -,  
- ।   (᫨ ⮫쪮  ⢨⥫  
裡  -. ᪨ -     ᮥ  -,
ᮧ ⠬   믮 襣    頥 १ 
-.

       ࠡ  ⠬  ࢥࠬ

 ⢥砥  믮 ਪ ணࠬ.   뫠  १  
SQL  -   믮   ࢥ.  ࢥ   믮
  ⥬, ⮡  १ .  ஢  
 믮  設-,  ⠪       ⢮
। ⠡,  ⠪ 室  ࠧ ணࠬ ᯥ祭
( ORACLE  ᫮ ).

        ࠧ묨 ﬨ ⥬ ORACLE

   ⥬  ᨨ 6  ᮥ  ࢥࠬ, ࠡ騬 
ࠢ ᨨ 5,     ᯮ짮 ⥩, 
⮫쪮  ᨨ 6.   ᨨ 5  ⠪   ࢥࠬ ᨨ 6.

        ᮡ ORACLE  SQL*Net

⥬ ORACLE, 䨣஢   SQL*Net, ন ।
.   :
*     㧫,⫨  㧫,  ஬  ॣ஢
* 뤠 , 뫠騥     ᪮쪨 㧫
* 믮  ꥤ      ⠡栬  ࠧ 㧫
* ।   ᯮ짮 ⠡  ࠧ 㧫

 饥 ६ ORACLE     SQL*Net    ন 
।  .   (UPDATE, DELETE,  INSERT  
DDL)  믮 ⮫쪮  㧫,  ஬    ᮥ. ᪮
    ⮫쪮  㧫,   ஬ ॣ஢, DBA
 ᯮ,  ⮡   室  ,     
⨢ ࠡ.

  ⢥   ,  ᫨   뫠  ⤥쭠,
ᨬ .      ᪮쪮   ⢥ 
,    - ᪮쪮; ᫨   ᪮쪮 ,    㤥
न஢ ᢮ ⥫쭮 ( ᭮ -  ⥢ 맮),   
  㤥, ᫨  न  㤥  ⠪   ࠧࠡ⪨ ⠡,
㯠 짮⥫  㭪樮஢ ⥬.

 ᪮쪮 짮⥫ ᮥ १      㯠  
ࠧ 㧫,      ॡ  DBA:
    * ஡ ⠫樨 (    ⠭ ணࠬ ᯥ祭,
       ⠪      㧫 ᯮ )
    * ࠭஢ 楫⭮     
    * ࠭஢  䥪⨢  ࠡ   ⤥ 㧫     楫




                                   -- 233 --



᫨   - ।, ⥭樠쭮 襥 ⢮ ਫ 
ࠧ ஢    .   ࠧ,   DBA 
⥩   䨣஢   ᮯ஢    ਪ
ணࠬ.    砥 ⠪  襥 ⢮ 襭,  
룮 , ,  ஥  襭    ஢.   
    ⥫⢠   ᫮,   室
ᬮ  ᮧ । ⥬,   ⪠ 㪠
  ਬ⥫쭮  DBA.

      ४祭  ࠧ㬥  㣨 

筮 設⢮ 짮⥫ 㤥 ࠡ    ⥬  ஬
ਪ ணࠬ  ᮮ⢥    ⮫쪮    
㣨 .  DBA   ᮮ⭥ 짮⥫  㬠稢묨
  , 뢠묨 DEFAULT HOSTS.   ⨬   
饭, ⮡   뫮 㪠뢠 ⥢ ⮪,    ..

    Host -  ᨭ    SQL*NET.  ४  ⥪饩  
     SET INSTANCE ⨫ SQL*DBA. ࢮ砫쭠
         (null)       ⮩
設,   ன 뫠   ६ ࠡ SQL*DBA.

   - ,  ன  ᮥ ᫥   (
 SET INSTANCE),    (ᮥ  祭  ).

o  砫 ਫ    ᠭ  SET INSTANCE (⠬ ) 
ᠭ 롮 㤠 ஢  믮 㭪権 DBA  㤠
.

      襭    ᯮ ਪ ணࠬ

 ।  ।  ࠡ⪨      ⮯ ਪ
ணࠬ      ⮯  .   ਢ 
䠪 롮 設  ࠧ饭 ਪ ணࠬ:

    *    㤮  ࠡ ᭮  짮⥫
    * ஢ 㧪 ࠭   ⭮ ६ ⢥
      ᥩ   饬
    * 㯭 ⥢ ணࠬ ᯥ祭   ᮥ 
      室 ஬
    *  ࠧ  ᮯ஢  ਫ     

     ।     ᯮ殮    
  ।  .   ᯮ  
ᯮ짮 , ࠧ饭 ணࠬ ᯥ祭, ᭮
,  ⠪ ࠭஢  㯠 짮⥫  ,
  室 (   ⮣).

 ࠧࠡ⪥ ⨬쭮 ।   奬  ࠡ⪨ DBA ,
 , 뢠 ᫥騥 :
    *   ᯮ  饥 ६ ?
    *    㤥  (INSERT) ᭮    ?
    *  ⢮ ࠧ ਫ 㤥 ᯮ짮 ?
    *    짮⥫ ਪ ணࠬ    ?
    *   㯭 ᥩ    饬 ?
    *  ॡ ஢ ந⥫쭮 ?
    *    ॡ    ?


                                   -- 234 --



 ᥣ  ⮣ ᮥ ࠭ ᨬ   
 ६饭   ᫨ﭨ    .  ᫨    ।
⨬쭮,   ᫥騥 २⢠:
    * ᭨ ⥢ 
    * 襥 ६ ⢥
    * ⥭樠쭮  筮 
    * 쭮 ࠢ 묨 묨
    * 業ࠫ쭮 ࠢ 묨 ﬨ 

᪮ 筮     襢, ⥫쭮 ࠭
    襣 ᯮ짮.

      ६饭   COPY

६饭    믮   COPY.  ஡ ᨭ⠪
      "ࠢ筨  짮⥫   SQL*Plus".  ஢
    㤠 㧫  㣮  (᫨    室  
। );   ⮬  室 ᮥ   㧫.
஬ ⮣, ᫥  ᪮   㤠 㧫  :

    INSERT INTO table_here
    SELECT * FROM table_there@dblink

 ᠭ ࠭祭  믮 ᮢ    । ⥬
  "ࠢ筨   짮⥫   SQL*Plus".

         痢   

     ᮥ     㤠 㧫 室 ᮧ . 
 ᮤন  ଠ    㭨쭮 䨪樨 "" 
 쭮   㣮.  - ।   㪠
 (DBLINK),   ᯥ (  )  짮⥫ 
஫,  ⢨⥫  -ࢥ. DBLINK ᮤন ᫥ ଠ:
    * ⥢ ⮪
    *  㧫
    *  
    * 짮⥫/஫ (易⥫쭮)
    * 樨 ⮪

 ਬ:

    D:LONDON:'LONDB':SCOTT/TIGER

,    㪠뢠 ᢮   짮⥫,  ᮥ
 ⭮ 짮⥫  -ࢥ.  䠪  
२⢠  । 裡.

DBLINK, ।塞   SQL -  ,   ᫮ 
- (.   USER_DB_LINKS, ALL_DB_LINKS  DBA_LINKS).

    CREATE [ PUBLIC ] DATABASE LINK dbname
    [ CONNECT TO username IDENTIFIED BY pwd ]
    USING 'netprefix:dbstring'

ਬ, ᫥ 뤠 ᫥饣 SQL -   - ।
:



                                   -- 235 --



    CREATE DATABASE LINK LONDB
    CONNECT TO CHARLES IDENTIFIED BY DICKENS
    USING 'D:THAMES'

   믮, ਬ, ᫥ :

    SQL> SELECT * FROM EMP@LONDB

஬ ⮣,    㤠 ⠡  । ᨭ, 뢠騩
 :

    CREATE SYNONYM EMP FOR EMP@LONDB;
    SELECT * FROM EMP;

        裡

筮 뢠 ,  ᮧ  짮⥫      
 ᪫⥫쭮 ᯮ짮.   ⮬ 砥 ᫮  
  㤠  ⮫쪮 । 짮⥫ ().  
⮣, ⮡ 㣮 짮⥫   㤠 ,    ᮧ
ᮡ⢥ .

     裡    饬 砥 ᯥ稢   . ᫨ 
᪮쪮 짮⥫    ⭮   㤠 ,
  ᮧ  (public) .

      騥  裡

饩 (PUBLIC) 뢠 ,  ᮧ 짮⥫   
  饣 ᯮ짮.  ⮬ 砥  짮⥫, ஬
室     㤠 ,  ᯮ짮 ᮧ
.         㤮,  ᫨  짮⥫  ஭
ࢥ  騩 , ਬ "⮩  ".    ⮤ 
᪮쪮 㦥  ᫥  ᭮  ,       㤮,  ⠪
  騩  ॡ   痢.

        롮 짮⥫  㯠  㤠 

 㯥      ORACLE   㪠 ⢨⥫ 
짮⥫  ஫ (䨪  짮⥫  - UID).

 ࠡ  । ,  室  ⮫쪮 ᢮ ᮡ⢥
UID  裡  쭮 ,   裡  㤠묨  㤥
ࠡ뢠  쭠 .

ଠ, 室  㯠  㤠  筠 ⮩,  
ॡ  ᮧ  裡.  ⢮ 짮⥫    
ᮥ  㤠 , ᯮ짮 騬,   ᥬ
  짮⥫  ,  짮⥫  짮
 祭. ᫥騥 ࠧ 㦤   ⮤.

      ᯮ짮  ⮢  饣 ⭮ 

 짮⥫  ᮥ    ,  ᯮ  騩 
 UID. २⢠ ⠪ ⮤   ᫥饬:
*  짮⥫,  騩   ,     ⮫쪮  UID,
  騩 室 ਢ


                                   -- 236 --



*     뫮,  騩   ਢ    ,  
   ⮫쪮   UID.

 ⮬ ⮤  ⪨,  易  ᭮:

* 業ࠫ UID   ਢ 㯠  ⠡栬, 室
   짮⥫,  ᫥⥫쭮 -  짮⥫   
  ,    ॡ

*  ⥭  ॢ襭 室 ਢ (⠪   UPDATE,
  INSERT,  DELETE)   믮 ॡ   ⮢

* 襭  ᥪ⭮  (ਬ - ࠧ襭 ஫) ⥭樠쭮 
,⠪   UID  ப ਢ  讬  ꥪ⮢
.

孨᪨   ⮬ ᯮᮡ ᮧ     ᯥ筮 
 짮⥫ ORACLE    -ࢥ,   ஬   
짮⥫:
            CREATE DATABASE LINK NODE1
            CONNECT TO NETUSER IDENTIFIED BY NETPASS USING 'dbstring';

 ⠪ ,    ⥬ 뤠:

    GRANT CONNECT TO NETUSER IDENTIFIED BY NETPASS
 ⥬ ।⠢ ᮮ⢥騥 ਢ  ⠡.

      㠫    ⮢

 ⢥ ୠ⨢  । ⮤,   㤠
 ᮥ  㠫쭮 UID  ࢥ.     
ਠ:    짮⥫  ᮡ⢥ UID ("  "),
 㯯 짮⥫, 믮  室  ࠡ,  ᮥ  
 UID ("  "). ᫥ ⮤  ஬ 
騬 UID  㭨묨 묨 ࠬ.

 २⢠ ⮣ ⮤   ᥡ:

* ᯮ 襥 ⢮ 䨪஢,     
  । ਢ,  ⨬ ਧ樨 ਢ
* ⠥  ⭮ ॢ襭 稩 ,  ᮮ⢥⢥,
  㢥稢 ᭮.

 ⪨  ⮤ :
*      㤠 짮⥫  -ࢥ  
  ᮧ  UID  祭   
* ⠪  ࠡ  ᪮쪮  ᫮    ( ন
  襥 ⢮ 짮⥫  痢 ).
* 室  न ⥫쭮 ஢  ࢥ 
  .

 짮⥫      ᢮  ᮡ⢥    
짮⥫ 㤠 :

    CREATE DATABASE LINK MYLINK
    CONNECT TO SCOTT2 IDENTIFIED BY TIGER2 USING 'dbstring';



                                   -- 237 --



 , 짮⥫  뫠   PUBLIC,  ᮤঠ 
짮⥫  ஫.  ⮬ 砥 ᯮ   짮⥫ 
஫:
           CREATE PUBLIC DATABASE LINK HQ USING 'dbstring';

 ஡  ଠ ᮤন  "ࠢ筮 㪮⢥   SQL".





















































                                   -- 238 --
