



             3                  




 ⮩   뢠 ⮤ ࠡ⪨ ⤥ ⮢ .  
ਬ, 뢠 ⠪ ⠭ 䬥᪨  樨   ᫮ 
 ⠭,   ⠪  । 㭪樨,  ᮫⭮ 祭   
ᨬ쭮 ப.  ᮤন ᫥騥 ࠧ:
          * 樨
          * 㭪樨
          *  ଠ⮢
          * ࠦ
          * ᫮

        樨

樨  㭪樨 믮 室 ;   ᯮ    
㬥⮢         १⮢.

樨 ⫨    㭪権  ⥬,   ।⠢ ᯥ樠묨 
ᨬ,    ६   㭪樨  ᯮ ᫥騩 ଠ:

function_name(argument1, argument2, ...)

設⢮ 権  ᯮ  ᨬ쭮  2  㬥,   
㭪権  ᯮ짮   .

  ਢ  ⠡  ਢ  浪 뢠 -
設⢠.  襬 㦤 設⢮ -  冷,  ஬ 樨 
믮. ਬ,  ࠦ  1+2*3  ᯥࢠ 2 㬭   
(१ 6),   ⥬ १ ਡ  1 ( 7),  ⠪  
㬭 믮 । ᫮.   ᨬ  浪 믮 
(.. 設⢠) ⢥   8  9.    
設⢮ 㯯 .


        䬥᪨ 樨

䬥᪨ 樨 ᯮ  ࠦ   栭, ᫮, 
⠭, 㬭   ᫮ 稭.    䬥᪮   
樨      ⠪ ᫮ 祭.    権 
ᯮ   ࠡ  ⠬.   ᫥饩 ⠡ ।⠢ 
䬥᪨ 樨  浪 뢠 設⢠:

       믮塞 㭪        ਬ

()              ଠ 冷  SELECT (X+Y)/(X_Y)...
               믮 権. -
               樨  ᪮ 믮-
                  ।.
+ -            砥 ⥫쭮  ...WHERE QTYSOLD=-1
               ⥫쭮 ࠦ.   ...WHERE -SAL < 0

* /            , ࠧ.       SELECT 2*X+1
                                          ...WHERE X>Y/2


                                    -- 46 --



+ -            ,            SELECT 2*X+1
                                          ...WHERE X>Y-Z

         樨

 樨 ᯮ  ࠦ,  ࠡ  ᨬ묨 
ப.   ᫥饩 ⠡ ਢ ⢥ ᨬ쭠 :

       믮塞 㭪        ਬ

||             ⥭ (楯)   SELECT 'NAME IS'||ENAME
               ᨬ 祭

 १ ⥭樨 ⠪ 砥 ᨬ쭮 祭.    
ப      ᨬ쭮 255 ᨬ;   ࠭祭 
⭮   १ ⥭樨 ᨬ ப.

        樨 ࠢ

樨 ࠢ ਬ  ᫮, ࠢ  ࠦ  
㣨.      ᫮, १ ࠢ  ࠦ  㣨 
    TRUE,   FALSE (.   ࠧ "᫮").  ᫥饩 
⠡ ਢ 樨 ࠢ SQL:

       믮塞 㭪        ਬ

()              ଠ -     ...NOT(A=1 OR B=1)
                設⢠ 権.
=              ஢  ࠢ⢮     ...WHERE SAL=10000
!=,^=,<>       ஢  ࠢ⢮   ...WHERE SAL!=10000
>              " 祬"              ...WHERE SAL>10000
<              " 祬"
>=             "  ࠢ"        ...WHERE SAL>=10000
<=             "  ࠢ"
IN             "  童      ...WHERE JOB IN
                ᯨ᪠"                   ('CLERK','ANALIST')

               ⥭ "=ANY"        ...WHERE SAL IN
                                          (SELECT SAL FROM EMP
                                          WHERE DEPTNO=30)
NOT IN         ⥭ "!=ALL"       ...WHERE SAL NOT IN
                FALSE       (SELECT SAL FROM EMP
                  NULL     WHERE DEPTNO=30)
ANY            ࠢ 祭  - ...WHERE SAL=ANY
                祭  ᯨ᪠    (SELECT SAL FROM EMP
                .  ।- WHERE DEPTNO=30)
               : =,!=,>,<,<=,>=.
ALL            ࠢ 祭      ...WHERE (SAL,COMM)>=ALL
               ᥬ 祭ﬨ  ᯨ᪠  ((1400,300),(3000,0))
                .  ।-
               : =,!=,>,<,<=,>=.

[NOT]          []   ࠢ      WHERE A BETWEEN 1
BETWEEN x      x    ࠢ y.    AND 9
AND y




                                    -- 47 --



[NOT]          TRUE, ᫨  -     WHERE EXISTS
EXISTS         頥 [ 頥]    (SELECT SAL FROM EMP
                  ப    WHERE DEPTNO=30)

[NOT]          " ᮯ⠢/ᮯ-
LIKE           ⠢  ᫥騬
               蠡".  "%" -
                 ᮯ⠢-
                  ப 
                  ᨬ,
               ஬ NULL - ப,  "_"
               ᮯ⠢  
                ᨬ. -
                ਢ  
               ࠧ " LIKE".

IS [NOT]       "஢ઠ  [] null.    WHERE JOB IS NULL
NULL           IS  ᯮ짮
                ஢ન  NULL.
               NULL 㦤   3
               " 몠 SQL".


         NOT IN

 ப    祭 false (   ப  롥), ᫨ 
-   ᯨ᪥  樨 NOT IN  祭 null. ਬ:

SELECT 'TRUE'
    FROM EMP
    WHERE DEPTNO NOT IN (5,15,null)

-  頥 ப,   ६ :

SELECT 'TRUE'
    FROM EMP
    WHERE DEPTNO NOT IN (5,15)

- ୥ 祭 TRUE'.  ਬ  頥 ப, ⮬ :

DEPTNO NOT IN (5,15,null)

 :

DEPTNO !=5 AND DEPTNO !=15 AND DEPTNO != null

   ᫮,   ࠢ  null,    १ null, 
१⮬ ᥣ ࠦ 㤥 null.  ᯥ筮  樨 
  ண拉,  ᮡ ᫨  뫠  .

        ᪨ 樨

᪨ 樨  ᯮ  ꥤ १⮢ ᪮쪨 
᫮.   AND ᯮ,  ப  㤮⢮  
᫮, OR -   ᫮.  ਬ,  ᫥饩 ࠧ WHERE   
SELECT  AND ࠭,   뤠 ⮫쪮 ப  ⮩ 
ਥ  ࠡ ࠭ 1984    ࠡ⪮    1000 ஢  :


                                    -- 48 --



SELECT * FROM EMP
  WHERE (HIREDATE < '01-JAN-84) AND (SAL > 1000)

 ⠡ ।⠢ ᪨ 樨  浪 뢠 
設⢠:

       믮塞 㭪        ਬ

()              ଠ -     SELECT...WHERE x=y
                設⢠ -      and (a-b or p=q)
               権.

NOT             १ ...WHERE NOT(JOB IS NULL)
               ᪮ ࠦ ...WHERE NOT(CODE  LIKE 'T%')
                                     ...WHERE NOT(SAL BETWEEN
                                              500 AND 999)
                                     ...WHERE NOT(A=1)
AND            ⠭  TRUE  ...WHERE A=1 AND B=1
               ᪮ ࠦ,
               ᫨  ᫮ TRUE.
OR             ⠭  TRUE  ...WHERE A=1 OR B=1
               ᪮ ࠦ,
               ᫨   ᫮ TRUE.

㭮 4-1  १ 樨 AND   ᫮ﬨ.

     Ŀ
        AND         true        false        null      
     ͵
        true        true        false        null      
     Ĵ
        false       false       false        false     
     Ĵ
        null        null        false        null      
     

p㭮 4-1  ⨭: AND

㭮 4-2  १ 樨  OR   ᫮ﬨ.

     Ŀ
         OR         true        false        null      
     ͵
        true        true        true         true      
     Ĵ
        false       true        false        null      
     Ĵ
        null        true        null         null      
     
p㭮 4-2  ⨭: OR

        樨  ⢠

樨  ⢠ ꥤ   १ ᪮쪨 ᮢ.   
᫥饩 ⠡  浪 뢠 設⢠ ਢ SQL - 樨  
⢠.



                                    -- 49 --



       믮塞 㭪        ਬ

UNION          ꥤ       ...SELECT...
               뤠  ࠧ-      UNION SELECT...;
                ப  ⤥-
                

INTERSECT      ꥤ       ...SELECT
               뤠  ࠧ-      INTERSECT SELECT...;
                ப  ᮢ

MINUS          ꥤ       ...SELECT...
               뤠  ࠧ-      MINUS SELECT...;
                ப, 뤠 -
                ᮬ,   .


砭: ᫨    ⠡    㡫騥 ,   
ᯮ짮  ⢥  権  UNION, MINUS, INTERSECT 뤠 
⮫쪮 .

㭮 4-3  ᪨    १ 権  ⢠. 
⥬  뢠 १, 頥 ORACLE.

                       

                          A             B
         SELECT *                Ŀ
         FROM A                  
         UNION       Ŀ
         SELECT *    
         FROM B      
                     ٱ
                                 
                                 

           A            B                    A              B
    Ŀ                              Ŀ
                                                   
    Ŀ           Ŀ           
                                                 
                                                 
                          
                                                   
                                  
     SELECT * FROM A                       SELECT * FROM A
     MINUS SELECT * FROM B                 INTERSECT SELECT * FROM B

             㭮 4-3  樨  ⢠.

         㣨 樨

 뢠 㣨 樨 몠 SQL:

       믮塞 㭪        ਬ




                                    -- 50 --



(+)            뢠,  ।-    WHERE DEPT.DEPTNO=
               騩 ⮫ - ⮫         EMP.DEPTNO(+)
               譥 ꥤ

[table.]*      롨ࠥ        SELECT * FROM EMP
               ⮫  ⠡. 
               ।  ⠡-
                 窮,  -  SELECT EMP.* FROM EMP
               ࠥ  ⮫ ⮩
               ⠡.

COUNT(expr)    頥 ᫮ ப,    SELECT COUNT(COMM)
                 expr  null.    FROM EMP

COUNT(*)       頥 ᫮ ப     SELECT COUNT(*)
                ⠡,  ᮤ-  FROM EMP
               騥 null.

ALL            頥 㡫騥   SELECT ALL * ...
               祭    -  ...COUNT(ALL DEPTNO)
               ॣ. (ALL - 㬠稢-
                 ⫨稥  DISTINCT)

DISTINCT        㡫騥 - DELECT DISTINCT *...
                   㤠
               㡫騥 祭    ...COUNT(DISTINCT
               ॣ⭮ ࠦ.         DEPTNO)...

PRIOR          । ⭮襭        CONNECT BY
               "-"  ॢ      PRIOR EMPNO=MGR
               . ࠦ  
                ᫮ (EMPNO) -
               ⠢ த⥫
               ப; ࠦ ࠢ
               (MGR) ।⠢ ப
               ॡ.  ᯮ짮-
                  ࠧ ॢ-
                ,   ⮫-
                 CONNECT BY.




















                                    -- 51 --




         LIKE

祭     ᯮ  ࠢ ᨬ ப   蠡.

।뫪    .
⠪      SELECT ....
                 WHERE char LIKE pattern

祢 ᫮ char           ࠦ  ⨯  CHAR.
 ࠬ                    ࠫ    
                              窨.   ᠭ expr ࠭  ⮩ 
                                text   3  㪮⢠.

               pattern        ࠦ  ⨯  CHAR,  ஬ 
                              ᯮ ᯥ樠 ᨬ ᮯ⠢ 
                               蠡 (%  _).
砭  ᯮ짮
  ਬ  "="  筮 ࠢ  ᨬ쭮 ப  
  㣮,  ᠬ     ᯮ  LIKE  ࠢ  
 ப  㣮.

 ࠧ LIKE   ࠢ ⮫  蠡,    ⠭⮩. ⮫ 
ᯥ । 祢 ᫮ LIKE.  
ਬ,    ⠪ :
SELECT SAL
   FROM EMP
   WHERE ENAME LIKE 'BL%'

   ᫥ ᮢ:
SELECT SAL
   FROM EMP
   WHERE ENAME = 'BL%'

SELECT SAL
   FROM EMP
   WHERE 'BL%' LIKE ENAME

 蠡      ᥡ  ᯥ樠 ᨬ,   묨 
 ᮯ⠢ ࠧ  ᨬ  祭 .   ન  
"_"  ᯮ    ࠢ ஢   ᨬ,    業 "%" 
-  ࠢ    ᨬ.  ,  ப '%'  
 ᮯ⠢  NULL.

     ᫮, ࠢ ᨬ ࠦ,   樨 LIKE 
 =,  ॣ  祭.   믮 ॣ஭ᨬ ࠢ 
   ᯮ짮 㭪樥 UPPER(), ਬ:

UPPER(ENAME) LIKE UPPER('sm%')

LIKE  ᯮ짮      ᪮ ࠦ, ࠡ饬  묨 
⨯ CHAR.  ᫨ LIKE ᯮ  ᪠  ஢ ⮫  
蠡,  २⢠   ᪮ , ᫨  ᨬ  
蠡 "%"  "_". ᫨    ⠪,  २⢠   
 ࠭, ⠪  ORACLE  ࠭ ࠢ ப 
⥬,   稭  ⭮ ᨬ.



                                    -- 52 --



 ᨬ "%"   "_"    ᪨    㭪樨 TRANSLATE.  
ਬ,  ᪠  㦠, ᮤঠ   ᨬ ન, 
 :

SELECT ENAME
   FROM EMP
   WHERE TRANSLATE(ENAME,'_','#') LIKE '%#%'

।騩 ਬ ᯮ 㭪 TRANSLATE  ८ࠧ "_"  "#".  
 ୥  㦠, ᮤঠ   #.

ਬ
᫮ ENAME  LIKE  'BL%'  砥 " TRUE, ᫨ 祭 ENAME 
稭   BL,   ᫥     ᨬ".   
᫥  祭 ਢ   뤠 TRUE:
BLAKE, BL, BLACK, BLUE

  ࠥ  ஫, ⠪  祭 Bl  bl  FALSE.
 ᫮ ENAME LIKE 'SMITH_'  ᫥騥 祭:  SMITHE, SMITHY, 
SMITHS,      ୮ 祭  SMITH,  ⮬  蠡 "_" 砥 
ᮯ⠢    筮     ᨬ.

易       " ࠢ",  ᨭ⠪᪮ ᠭ expr,
ࠧ         SELECT -    5  "ࠢ筨  SQL - ࠬ"; 
               ࠧ WHERE   6 ⮣ 㪮⢠  ( ࠧ  "ࠧ  
                SELECT").

































                                    -- 53 --




        㭪樨

㭪樨  ᥡ 筮 .    㣨 ࠡ  㫥  
 㬥⠬      १⮢.    㣨 
ࠡ  ⤥묨 ⠬ .

樨 ⫨  㭪権 ⥬,  ᯮ ଠ "argument1   
argument2",    ६  㭪樨 - function_name(argument1,argument2,...). 
Argument -   짮⥫ ६  ⠭.

設⢮ 権  ᯮ  ᨬ쭮  㬥;
 㭪樨   ਭ      㬥⮢.

  㭪樨  ᫥騥 ਧ:
*   㭪樨   १  ப
*   㭪樨     㬥⮢
*   㭪樨    묨
*  㭪樨   ᯮ짮  ,     ᯮ짮 
  짮⥫᪨ ६- , ⮫  ࠦ ᮮ⢥饣 ⨯
*   㭪樨  ࠡ    ப, 頥 ᮬ,  
   롮ન ᫥ ப

  㬥 ਭ ᫥騥 ᮪饭  㬥⮢:

饭                ᭥ 㬥
㬥

char                      쭠 ⠭  
                          窠  ࠦ ⨯ CHAR.

d  e                   ⠭  ࠦ ⨯ DATE.

m  n                    ᫮ ⠭  -
                           ⨯ NUMBER.

raw                       ࠦ ⨯ RAW.

rowid                     ࠦ ⨯ ROWID.

*                             ⥪
                          㭪樨.

expr                      ࠦ  ⨯.

 ᫮ 㭪樨

᫮ 㭪樨 ਭ  室      室
᫮ 祭.   ᫥饩 ⠡ 뢠 ᫮
㭪樨 SQL:


ABS      ⠪   ABS(n)
         祭  頥 ᮫ 稭 n.

         ਬ      SELECT ABS(-15) "Absilute" FROM DUAL



                                    -- 54 --



                         Absolute
                         --------
                               15

CEIL     ⠪   CEIL(n)
         祭  頥 襥 楫, 襥
                      ࠢ n.
         ਬ      SELECT CEIL(15.7) "Celling" FROM DUAL

                         Celling
                         -------
                              16

FLOOR    ⠪   FLOOR(n)
         祭  頥 襥 楫, 襥 
                     ࠢ n.
         ਬ      SELECT FLOOR(15.7) "Floor" FROM DUAL

                         Floor
                         -----
                            15

MOD      ⠪   MOD(m,n)
         祭  頥 ⮪   m  n.

         ਬ      SELECT MOD(7,5) "Modula" FROM DUAL

                         Modula
                         ------
                              2

POWER    ⠪   POWER(m,n)
         祭  頥 m  ⥯ n. n  
                     楫,   訡.
         ਬ      SELECT POWER(3,2) "Raised" FROM DUAL

                         Raised
                         ------
                              9

ROUND    ⠪   ROUND(n[,m])
         祭  頥 n, 㣫  m 
                     ᫥ 筮 窨; ᫨ m 饭,
                     㣫  0 .  㣫
                     ᫥  筮 窨 m  
                     ⥫. m   楫.

         ਬ      SELECT ROUND(15.193,1) "Round" FROM DUAL

                         Round
                         -----
                         15.2

                     SELECT ROUND(15.193,-1) "Round" FROM DUAL

                         Round
                         -----
                         20

                                    -- 55 --




SIGN     ⠪   SIGN(n)
         祭  ᫨ n<0, 㭪 頥 -1; ᫨
                     n=0, 㭪 頥 0   n>0
                     頥 1.

         ਬ      SELECT SIGN(-15) "Sign" FROM DUAL

                         Sign
                         ----
                           -1

SQRT     ⠪   SQRT(n)
         祭  頥  ७   n; ᫨
                     n<0, 頥 NULL.  㭪 -
                     頥 ⢨⥫ (real) १.

         ਬ      SELECT SQRT(25) "Square root" FROM DUAL

                         Square root
                         -----------
                                   5

TRUNC    ⠪   TRUNC(n[,m])
         祭  頥 n    祭묨 m 訬
                     ࠧ鸞. ᫨ m ,  ᥪ-
                       0 ࠧ鸞 ( 楫).  ᫨ m -
                     ⥫쭮, 祭 ࠧ冷  (-
                     㫥) 믮    -
                      窨.

         ਬ      SELECT TRUNC(15.79,1) "Truncate" FROM DUAL

                         Truncate
                         --------
                             15.7

                     SELECT TRUNC(15.79,-1) "Truncate" FROM DUAL

                         Truncate
                         --------
                               10


 ᨬ 㭪樨

 ᨬ  㭪樨 ॡ ᨬ 室
,     ᨬ,  ⠪    ᫮
祭.

 ᨬ 㭪樨, 騥 ᨬ
祭

CHR      ⠪   CHR(n)
         祭  頥 ᨬ, 騩 ᮮ⢥-
                     饥 祭 n   ASCII  EBCDIC.

         ਬ      SELECT CHR(75) "Character" FROM DUAL

                                    -- 56 --



                         Character
                         ---------
                         K

INITCAP  ⠪   INITCAP(char)
         祭  頥 char,   ᫮  ஬
                     稭  ய᭮ 㪢,  ⠫-
                      - .

         ਬ      SELECT INITCAI('MR. SAMUEL HILLHOUSE')
                     "Capitalized"
                          FROM DUAL

                         Capitalized
                         --------------------
                         Mr. Samuel Hillhouse

LOWER    ⠪   LOWER(char)
         祭  頥 char,    ᨬ ண
                     ॢ  

         ਬ      SELECT INITCAI('MR. SAMUEL HILLHOUSE')
                     "Lowercase"
                          FROM DUAL

                         Lowercase
                         --------------------
                         mr. samuel hillhouse

LPAD     ⠪   LPAD(char1,n [,char2])
         祭  頥 char,  ᫥ 
                     n ᨬ ⥫ char2. ࠧ-
                      祭  char2 - ஡.

         ਬ      SELECT LPAD('Page 1',14,'*.')
                     "LPAD example"
                          FROM DUAL

                         LPAD example
                         ---------------
                         .*.*.*.*.Page 1

LTRIM    ⠪   LTRIM(char,[set])
         祭     ᨬ    char,  
                      ᨬ  char 室  set. -
                     砭  set ''.

         ਬ      SELECT LTRIM('xxxXxxLAST WORD','x')
                     "Left trim example"
                          FROM DUAL

                         Left trim example
                         -----------------
                         XxxLAST WORD

REPLACE  ⠪   REPLACE(char,search_string
                     [,replacement_string])
         祭       char         宦

                                    -- 57 --



                     search_string     replacement_string.
                     ᫨ replacement_string  㪠, 
                     宦 search_string 㤠. ᫨
                      㪠    replacement_string,  
                     search_string, 㭪 頥 NULL.
                     㭪 REPLACE    
                     㭪樨 TRANSLATE,  ᯥ稢
                         ᨬ.    REPLACE
                     ᯥ稢  ப  ப, 
                     ⠪ 㤠 ᨬ ப.

         ਬ      SELECT REPLACE('JACR & JUE','J','BL')
                     "Changes"
                          FROM DUAL

                         Changes
                         ------------
                         BLACK & BLUE

RPAD     ⠪   RPAD(char1,n [,char2])
         祭  頥 char1,  ࠢ 
                     n ᨬ ⥫ char2, -
                      ⮫쪮 ࠧ,  ᪮쪮  室.
                     ᫨ char2 饭, ந -
                      ஡.

         ਬ      SELECT RPAD('ENAME',10,'x')
                     "RPAD example"
                          FROM EMP
                          WHERE ENAME = 'TURNER'

                         RPAD example
                         ------------
                         TURNERxxxx

RTRIM    ⠪   RTRIM(char [,set])
         祭  頥 char  騬 ᨬ-
                     , 祭묨  ࠢ ᫥ ᫥
                     ᨬ,  室饣  set.  ᫨  set
                     饭, ।  㬮砭 ''.

         ਬ      SELECT RTRIM('TURNERxxXxx','x')
                     "Right trim example"
                           FROM DUAL

                         Right trim example
                         ------------------
                         TURNERxxX

SOUNDEX  ⠪   SOUNDEX(char)
         祭  頥 ᨬ ப, ।⠢-
                       ᥡ ᨬ쭮 ।⠢
                     ᫮ (᫮),   char  
                     ⠪ ᠭ.   㭪 
                     ࠢ ᫮  ࠧ  ᠭ-
                     ,   .



                                    -- 58 --



         ਬ      SELECT ENAME
                          FROM EMP
                          WHERE SOUNDEX(ENAME) =
                                SOUNDEX('SMYTHE')

                         ENAME
                         -----------
                         SMITH

SUBSTR   ⠪   SUBSTR(char, m[,n])
         祭  頥  char, 稭  ᨬ-
                       ஬ m   n ᨬ. -
                      n 饭 -     char.  ࢠ
                      char 1.

         ਬ      SELECT SUBSTR('ABCDEFG',2,3)
                     "Substring"
                          FROM DUAL

                         Substring
                         ---------
                         BCD

TRANSLATE ⠪  TRANSLATE(char,from,to)
          祭 頥 char    ᥬ  묨
                     ᨬ from  to.  ᮯ⠢
                     ᨬ  .  TRANSLATE  㤠-
                      ᨬ.

          ਬ    SELECT TRANSLATE('HELLO! THREE!','!','-')
                     "Translate example"
                         FROM DUAL

                         Translate example
                         -----------------
                         HELLO- THREE-

UPPER    ⠪   UPPER(char)
         祭  頥 char  ᥬ ᨬ, -
                     ॢ묨  孨 ॣ.

         ਬ      SELECT UPPER('Mr. Rogers')
                          FROM DUAL

                         UPPER('Mr. Rogers')
                         -------------------
                         MR. ROGERS

 ᨬ 㭪樨, 騥 ᫮ 祭


ASCII    ⠪   ASCII(char)
         祭  뤠 祭    ᫥⥫쭮
                     ᫨ﭨ  ࢮ ᨬ  char. -
                     ⢥饩 㭪樨 EBCDIC  -
                     ,   設,  ࠡ  



                                    -- 59 --



                     EBCDIC  㭪 뤠 ᮮ⢥-
                     饥 祭  ᫥⥫쭮 ᫨-
                     ﭨ EBCDIC.

         ਬ      SELECT ASCII('Q') FROM DUAL

                         ASCII('Q')
                         ----------
                                 81

INSTR    ⠪   INSTR(char1,char2[,n[,m]])
         祭  뤠  m -  宦 char2 
                     char1;  稭  n -  ᨬ-
                       char1. ᫨ "m" 饭, ।-
                      1,    ⭮   "n". -
                      뤠   ⭮⥫쭮   ࢮ
                     ᨬ  char1,  ᫨ n > 1.

         ਬ      SELECT INSTR('MISSISSIPPI','S',5,2)
                     "In string example"
                          FROM DUAL

                         In string example
                         -----------------
                                         7

LENGTH   ⠪   LENGTH(char)
         祭   char.

         ਬ      SELECT LENGTH('ELEPHANT')
                     "Length"
                          FROM DUAL

                         Length
                         ------
                              8


NLSSORT  ⠪   NLSSORT(char)
         祭  頥  祭 ᫥⥫쭮
                     ᫨ﭨ  char, ᭮  ⭮
                     樮쭮 몥.    ଠ樥  
                     "প 樮 몮" -
                       ਫ F "ORACLE RDBMS 㪮-
                     ⢠   ".

         ਬ      SELECT NLSSORT('Q') "Sequence #"
                          FROM DUAL

                         Sequence #
                         ----------
                               5100


㯯 㭪樨




                                    -- 60 --



㯯 㭪樨  १, ᭮  -
 ப ( ⫨稥     㭪権,  
१    ப).   ࠧ १ 
訥 㯯 ᯮ ࠧ GROUP BY  SELECT.

ࠧ DISTINCT ⠢  㯯  㭪樨  ᬠਢ
⮫쪮 ⫨騥 祭 ࠦ; ALL 砥  -
७   祭,    㡫騥.   ਬ,
। 祭  1,1,1,3  DISTINCT ࠢ 1.5,    ALL
 㤥 ࠢ 2.  (  ਣ,    ࠢ쭮  
 :  ALL=1.5;  DISTINCT=2. - ਬ. ॢ.) ᫨ 
 SELECT 饭   ࠧ, । ALL.

  㭪樨 (஬ COUNT(*)) ய᪠ 祭 NULL.

᫨  㪠뢠 "expr",  ⨯  㬥   
CHAR, NUMBER  DATE.


AVG      ⠪   AVG([DISTINCT | ALL] n)
                                     
         祭  頥 । 祭 n, 
                     祭 null.

         ਬ      SELECT AVG(SAL) "Average" FROM EMP

                         Average
                      ----------
                      2073.21429


COUNT(expr) ⠪  COUNT([DISTINCT | ALL] expr)
                                         
            祭 頥 ⢮ ப,  expr
                        NULL.

            ਬ     SELECT COUNT(JOBS) "Count"
                            FROM EMP

                         Count
                         -----
                             4

                       SELECT COUNT(DISTINCT JOB) "Jobs"
                            FROM EMP

                         Jobs
                         ----
                            5

COUNT(*) ⠪   COUNT(*)
         祭  頥 ᫮ ப  ⠡, -
                      㡫騥  ᮤঠ騥 NULL.

         ਬ      SELECT COUNT(*) "Total" FROM EMP




                                    -- 61 --



                         Total
                         -----
                            14


MAX      ⠪   MAX([DISTINCT | ALL] expr)
                                     
         祭  頥 ᨬ쭮 祭 expr.

         ਬ      SELECT MAX(SAL) "Maximum" FROM EMP

                         Maximum
                         -------
                         5000


MIN      ⠪   MIN([DISTINCT | ALL] expr)
                                     
         祭  頥 쭮 祭 expr.

         ਬ      SELECT MIN(HIREDATE) "Minimum Date"
                          FROM EMP

                         Minimum Date
                         ------------
                         17-DEC-80


STDDEV   ⠪   STDDEV([DISTINCT | ALL] n)
                                        
         祭  頥 ।筮 ⪫
                     n,  祭 null.

         ਬ      SELECT STDDEV(SAL) "Deviation" FROM EMP

                         Deviation
                         ----------
                         1182.50322


SUM      ⠪   SUM([DISTINCT | ALL] n)
                                     
         祭  頥 㬬 祭 n.

         ਬ      SELECT SUM(SAL) "Total" FROM EMP

                         Total
                         -----
                         29025


VARIANCE ⠪   VARIANCE([DISTINCT | ALL] n)
                                          
         祭  頥 ᯥ n,  -
                      null.

         ਬ      SELECT VARIANCE(SAL) "Variance"
                          FROM EMP

                                    -- 62 --



                         Variance
                       ----------
                       1389313.87
                                























































                                    -- 63 --



㭪樨 ८ࠧ

㭪樨 ८ࠧ  ॢ  祭     ⨯
  㣮.  饬 砥 ⠪ 㭪 ८ࠧ
뢠 datatypeTOdatatype.  datatype -  室
६,  ன - 室.  ᫨   㭪樨 㪠
⮫쪮  室 ⨯,   室    -
⢨⥫ ⨯  ⥬ ORACLE.

 ⮬ ࠧ 뢠 㭪樨 ८ࠧ ORACLE:


CHARTOROWID ⠪  CHARTOROWID(char)
            祭 ८ࠧ 祭   ⨯ CHAR
                        ROWID.

            ਬ     SELECT ENAME
                            FROM EMP
                            WHERE ROWID =
                            CHARTOROWID('0000000F.0003.0002')

                         ENAME
                         -----
                         SMITH

CONVERT  ⠪   CONVERT(char [,dest_char_set
                                  [,source_char_set] ] )
         祭  ८ࠧ뢠    ࠧ묨
                     ॠﬨ  ᨬ쭮 .
                     ਬ,  ᨬ DEC 8 bit   ᨬ-
                      HP 8 bit.
                     dest_char_set -  ᨬ쭮 ,
                        㤥 믮 ८ࠧ-
                     .     ⮫ ,
                     ᮤঠ饣  ᨬ쭮 
                      ᨬ  ࠫ. 稢
                     祭 'US7ASCII'.
                     source_char_set -  ᨬ쭮 -
                     ,   ஬   ࠭  .
                         ⮫, ᮤঠ饣
                            ᨬ  ࠫ.
                     稢 - ⥪饥  祭  -
                      <char_set>  (ࠬ  LANGUAGE 
                     䠩 INIT.ORA).
                      ஡  ଠ   ।⢥
                     "প 樮  몮"  
                     ௭    ਫ   F  "ORACLE
                     RDBMS 㪮⢠    
                     ".
          ᫥騥 ⠭ ᨬ :

         US7ASCII    (㬠稢) ᨬ  US 7-bit
                     ASCII
         WE8DEC      ய᪨ 8-bit ASCII  DEC
         WE8HP       ய᪨ 8-bit ASCII  HP
         F7DEC       ࠭᪨ 7-bit ASCII  DEC
         WEIBMPC     ய᪨ 8-bit ASCII,  ᯮ-
                     㥬  IBM PC.

                                    -- 64 --



         ਬ      SELECT ('NEW WORD','US7ASCII','WE8HP')
                     "Conversion"
                          FROM DUAL

                         Conversion
                         ----------
                         NEW WORD

HEXTORAW ⠪   HEXTORAW(char)
         祭  ८ࠧ ᨬ쭮 祭, -
                     饥  ⭠   -
                        (ਣ    ᥭ   
                     ⮫ ⨯ RAW).

         ਬ      INSERT INTO GRAPHICS (RAW_COLUMN)
                          SELECT HEXTORAW('7D')
                          FROM DUAL

RAWTOHEX ⠪   RAWTOHEX(raw)
         祭  ८ࠧ raw  ᨬ쭮  -
                     , 饥      ⭠
                     .


         ਬ      SELECT RAWTOHEX(RAW_COLUMN) "Graphics"
                          FROM GRAPHICS

                         Graphics
                         --------
                         7D


ROWIDTOCHAR  ⠪   ROWIDTOCHAR(rowid)

             祭  ८ࠧ 祭 ROWID  ⨯
                          CHAR.   १ ८-
                          ᥣ   砥  ப
                          18 ᨬ.

             ਬ      SELECT ROWID
                         FROM GRAPHICS
                         WHERE ROWIDTOCHAR(ROWID) LIKE '%F38%'

                         ROWID
                         ------------------
                         00000F38.0001.0001

TO_CHAR,     ⠪   TO_CHAR(n [,fmt])
८ࠧ-   祭  ८ࠧ 祭 ⨯ NUMBER
 ᥫ               ⨯ CHAR,  ᯮ 易⥫-
                          ப ଠ. fmt  
                         ᫮ ଠ⮬. ஡ ଠ
                         ᠭ    ࠧ  " ଠ-
                         ⮢".᫨ fmt 饭,  n ८ࠧ-
                         뢠  ᨬ쭮 祭 -
                         , 筮   ࠭ 
                          .


                                    -- 65 --



             ਬ      SELECT TO_CHAR(17145,'$099,999')
                         "Char"
                              FROM DUAL

                         Char
                         ---------
                         $017,145


TO_CHAR,     ⠪   TO_CHAR(d [,fmt])
८ࠧ- 祭  ८ࠧ 祭 ⨯ DATE 
                   ⨯ CHAR,  ᯮ 易⥫
                         ப  ଠ.  fmt    
                         ଠ⮬ . ଠ ᠭ 
                          ࠧ  " ଠ⮢".  ᫨
                         fmt 饭, d ८ࠧ  ⠭-
                          ଠ ⥬ ORACLE, "DD-
                         MON-YY".

                         ଠ  ᫮ ᨬ १,
                         頥 㭪樥  TO_CHAR -
                           㪠 祭 fmt.

             ਬ      SELECT TO_CHAR(HIREDATE,'Month DD,YYYY')
                         "New data format"
                             FROM EMP WHERE ENAME = 'SMITH'

                         New date format
                         ---------------------------------
                         December 17, 1980
                         




























                                    -- 66 --



TO_DATE      ⠪   TO_DATE(char [,fmt])

             祭  ८ࠧ char  祭 ⨯
                         . 騥 祭 , 
                          ..  ਬ  砥,  ᫨
                            筮 ।  -
                         . fmt -  ᨬ쭮  -
                           ଠ ,  ஥ ᯥ-
                          ଠ char.  ଠ 
                         ଠ ।⠢   ,  
                         ࠧ " ଠ⮢". ᫨ fmt
                         饭, 祭    ᨬ쭮
                         ଠ     "DD-MON-
                         YY". ᫨  ଠ  "J" - ᪨,
                          char   ᫮.

             ਬ      INSERT INTO BONUS (BONUS_DATE)
                         SELECT TO_DATE('January 15, 1989',
                                        'Month dd, YYYY')
                              FROM DUAL

TO_NUMBER    ⠪   TO_NUMBER(char)
             祭  ८ࠧ뢠 char,    騩
                         ᨬ ।⠢  ᫠  
                         祭 ⨯ NUMBER.

             ਬ      UPDATE EMP
                           SET SAL = SAL +
                           TO_NUMBER(SUBSTR('$100 raise',2,3))
                           WHERE ENAME = 'BLAKE'


㭪樨  ࠡ  ⠬

 㭪樨 ࠡ  ⠬ ⥬  ORACLE.    㭪樨
 ࠡ  ⠬  祭 ⨯ DATE ( ᪫-
祭 MONTHS_BETWEEN,  頥 ᫮ 祭).

ADD_MONTHS   ⠪   ADD_MONTHS(d,n)
             祭  頥  d, 㢥祭  n
                         楢. n   楫   -
                           ⥫.

             ਬ      SELECT ADD_MONTHS(HIREDATE,12)
                         "Next year"
                              FROM EMP
                              WHERE ENAME = 'SMITH'

                         Next year
                         ---------
                         17-DEC-81


LAST_DAY     ⠪   LAST_DAY(d)
             祭  頥  ᫥   -
                         , ᮤঠ饣  d.    
                         । ⢠   -
                          .

                                    -- 67 --



             ਬ      SELECT LAST_DAY(SYSDATE) "Last"
                              FROM DUAL

                         Last
                         -----------------
                         31-AUG-89


MONTHS_BETWEEN ⠪ MONTHS_BETWEEN(d,e)
             祭  頥 ⢮ 楢 
                         ⠬ d  e.  ᫨ d  
                         , 祬 e,  १ ⥫-
                         , ᫨    ࠭  - -
                         ⥫. ஡    १
                         砥  31 -  .

             ਬ      SELECT MONTHS_BETWEEN('02-feb-86',
                                               '01-jan-86')
                         "Months"
                              FROM DUAL

                         Months
                         ----------
                         1.03225806


NEW_TIME     ⠪   NEW_TIME(d,a,b)
             祭  頥   ६   ६-
                            b,     ६ 
                         ६  a ࠢ d.  a  b  -
                          ᨬ ࠦ, ਭ-
                         騥 ᫥騥 祭:

                         AST,ADT ⫠᪮   ⠭⭮
                                  ⫠᪮  ६
                         BST,BDT ਭ ⠭⭮ 
                                  ६
                         CST,CDT ࠫ쭮 ⠭⭮ 
                                  ६
                         EST,EDT 筮 ⠭⭮ 
                                  ६
                         GMT     । ਭ᪮ ६
                         HST,HDT ⠭⭮      
                                 ६ ᪨-
                         MST,MDT ⠭⭮      
                                 ६ ⠭
                         NST     ⠭⭮ ६ 㭫
                         PST,PDT ⫠᪮   ⠭⭮
                                   ६
                         YST,YDT ⠭⭮      
                                 ६ 

             ਬ      SELECT
                         TO_CHAR(
                         NEW_TIME(TO_DATE(17:47','hh24:mi'),
                                  'PST','GMT'),
                         'hh24:mi') "GREENWICH TIME"
                              FROM DUAL

                                    -- 68 --



                         GREENWICH TIME
                         --------------
                         01:47


NEXT_DAY     ⠪   NEXT_DAY(d,char)
             祭  頥   ,  ᯥ-
                          char, ࢮ , ᫥-
                         饩  ⮩, ।塞 d.

             ਬ      ᫥饬 ਬ 頥 -
                          ᫥饣  ୨  ᫥   17
                          1989 .

                         SELECT NEXT_DAY('17-MAR-89','TUESDAY')
                         "Next Day"
                              FROM DUAL

                         Next Day
                         ---------
                         29-MAR-89


ROUND        ⠪   ROUND(d [,fmt])
             祭  頥 d,  㣫  ᭮-
                          fmt.  fmt ࠧ㬥  -
                         訩 .
                          ⠫ﬨ 㭪権 ROUND    TRUNC
                             ࠧ "ROUND 
                         TRUNC".

             ਬ      SELECT ROUND(TO_DATE('27-OCT-88'),'YEAR')
                         "FIRST OF THE YEAR"
                              FROM DUAL

                         FIRST OF THE YEAR
                         -----------------
                         01-JAN-89
                         




















                                    -- 69 --




SYSDATE  ⠪   SYSDATE

         祭  頥 ⥪   ६.  -
                     ⮢  ॡ.

         ਬ      SELECT SYSDATE FROM DUAL

                         SYSDATE
                         ---------
                         19-MAR-89

TRUNC    ⠪   TRUNC(d [,fmt])
         祭  頥   ६,  ਢ 
                     㪠   fmt 祭 (㣫 
                      ஭).   㬮砭 㤠
                     ६   .  .  ⠪
                     ᫥騩 ࠧ "ROUND  TRUNC".

         ਬ      SELECT TRUNC(TO_DATE('28-OCT-88','YEAR')
                     "First of the Year"
                          FROM DUAL

                         First of the Year
                         -----------------
                         01-JAN-88


ROUND  TRUNC

 ⠡ 뢠  ଠ  ᮮ⢥-
騩 ६ ਮ  㭪権 ROUND  TRUNC.   㬮-
  । "dd",   砥 ਢ ६
   㭮.

 ଠ             (ਮ)

CC,SCC                    
SYYY,YYYY,YEAR,            (㣫  1 )
SYEAR,YYY,YY,Y
Q                         ⠫ (㣫  16 ᫮
                                   ண )
MONTH,MON,MM               (㣫  16 ᫮)
WW                        砫쭠  
W                         砫쭠  
DDD,DD,J                  
DAY,DY,D                  襥 ᥭ
HH,HH12,HH24              
MI                        
         









                                    -- 70 --



㣨 㭪樨

DECODE   ⠪   DECODE(expr, search1, result1,
                                 [search2, result2,] ...
                                 [default] )
祭  expr ࠢ      祭
            search  頥 result,  ᫨  expr
            ࠢ search. ᫨  ࠢ, 㭪-
             DECODE 頥 祭 default.
            ᫨ default , ।-
             null.
            expr       ⨯,  search
              ⮣  ⨯,     expr.
            頥 祭 ਢ  ⮬
             ⨯,    result.

ਬ      SELECT ENAME,DECODE(MGR, 7934, 'SMITH',
            7251, 'JONES', 7839, 'KING', 'NONE') Mgr
                 FROM EMP

                ENAME        MGR
                -----------  ----------
                JONES        KING
                CLARK        KING
                OAKLEY       NONE
                FORD         JONES


DUMP     ⠪   DUMP (expr [,display_format
                           [,start_position [, length]]])

祭  뤠 祭 ࠦ  ७
            ଠ. ⢨⥫묨 祭ﬨ 
            display_format :  8 -  -
            筮 ⥬,  10 -  筮,
            16 -  ⭠筮,  17  -  
            ᨬ쭮. start_position     length
            ।,   १ 
            뤠.   㬮砭  뤠  
            १.

ਬ     SELECT DUMP(ENAME) "ASCII"
                 FROM EMP
                 WHERE ENAME = 'SCOTT'

                ASCII
                ----------------------------
                Type=1 Len=5: 83,67,79,84,84

            SELECT DUMP(ENAME) "OCTAL"
                 FROM EMP
                 WHERE ENAME = 'SCOTT'

                OCTAL
                ---------------------------------
                Type=1 Len=5: 123,103,117,124,124



                                    -- 71 --



            SELECT DUMP(ENAME) "CHAR"
                 FROM EMP
                 WHERE ENAME = 'SCOTT'

                CHAR
                -----------------------
                Type=1 Len=5: S,C,O,T,T


GREATEST ⠪   GREATEST(expr [,expr] ...)
祭  頥 襥 祭  ᯨ-
            . । 믮 ࠢ  -
            ࠦ (expr) ८ࠧ뢠  ⨯
             ࢮ.

ਬ      SELECT GREATEST('HARRY','HARRYOT','HAROLD')
            "GREATEST"
                 FROM DUAL

                GREATEST
                --------
                HARRIOT

LEAST    ⠪   LEAST(expr [,expr] ...)

祭  頥 襥 祭  ᯨ-
            . । 믮 ࠢ  -
            ࠦ (expr) ८ࠧ뢠  ⨯
             ࢮ.

ਬ      SELECT LEAST('HARRY','HARRYOT','HAROLD')
            "LEAST"
                 FROM DUAL

                LEAST
                --------
                HAROLD


NVL      ⠪   NVL(expr1, expr2)

祭  ᫨ expr1   ࠢ   NULL,   頥
            expr2; ᫨ expr1  ࠢ NULL,  -
            頥 expr1.    頥
            祭     ⥬  ,    
            expr1.

ਬ      SELECT ENAME,
            NVL(TO_CHAR(COMM),'NOT APPLICATABLE')
            "COMMISSION"
                 FROM EMP
                 WHERE DEPTNO = 30

                ENAME         COMMISSION
                ------------- -----------
                ALLEN         300
                WARD          500
                MARTIN        1400

                                    -- 72 --



                BLAKE         NOT APPLICATABLE
                TURNER        0
                JAMES         NOT APPLICATABLE


UID      ⠪   UID

祭  頥 㭨쭮 ᫮,  祭-
               짮⥫ (-
             ⢥ UID  짮⥫).
            㬥⮢  ॡ.

ਬ      SELECT USER, UID FROM DUAL

                USER            UID
                ------------- -----
                OPS$KING          9


USER     ⠪   USER

祭  頥    ⥪饣  짮⥫
            ORACLE.  㬥  㦤.

ਬ      SELECT USER, UID FROM DUAL

                USER            UID
                ------------- -----
                OPS$KING          9


USERENV  ⠪   USERENV(option)
祭  頥 ଠ ⨯ CHAR   -
            ⥫/ᥠ,  ᯮ㥬  ᯥ-
              ਫ ⠡ ୠ
            ॣ樨 㯠.   ⠡
            뢠 祭,  頥  
             ⢨⥫쭮 樨 option:

            option      頥 祭
            
            'ENTRYID'   㯭     䨪
                         ॣ樨
            'SESSIONID' 䨪   ॣ樨
                        ᥠ 짮⥫
            'TERMINAL'  䨪     ନ
                        짮⥫  樮
                        ⥬
            'LANGUAGE'  ᯮ㥬   ( -
                        ।  ࠬ LANGUAGE
                        䠩 INIT.ORA

ਬ      SELECT USERENV('LANGUAGE') "Language"
                 FROM DUAL

                Language
                -------------------------
                AMERICAN_AMERICA.US7ASCII

                                    -- 73 --




VSIZE    ⠪   VSIZE(expr)

祭  頥 ⢮ ⮢, ᯮ-
             ORACLE  ࠭   ७
             expr.

ਬ      SELECT ENAME, VSIZE(ENAME) "BYTES"
                 FROM EMP
                 WHERE DEPTNO = 10

                ENAME          BYTES
                ------------ -------
                CLARK              5
                KING               4
                MILLER             6


         ଠ⮢

 ଠ⮢ ᯮ   楫ﬨ:
*  ଠ 뤠 ⮫
* ।⠢  ORACLE 祭 ଠ,  ⫨筮  ࠧ㬥.

 ଠ ᯮ  㭪  TO_CHAR    TO_DATE.
 ⢥  㭪樨  TO_CHAR  TO_DATE   ਬ 
᪮쪮  ଠ⮢.

         ଠ 뤠

 ଠ   ਬ    뤠 ⮫殢, 
頥 ஬ SELECT.  ଠ        ॠ쭮 
७ ।⠢  ⮫.

ਬ, ⮡ 뤠 ᨮ  㦠  ⤥ 30  ⠡ EMP,  
ᯮ 騥 ᨬ ,   묨 ६ ࠬ   
    樨, :

SELECT ENAME EMPLOYEE, TO_CHAR(COMM,'$0,999.99') COMMISSION
     FROM EMP
    WHERE DEPTNO = 30

EMPLOYEE      COMMISSION
-----------   ----------
ALLEN            $300.00
WARD             $500.00
MARTIN         $1,400.00
BLAKE
TURNER             $0.00
JAMES


 ,    㭪 TO_CHAR 頥 NULL   㦠,  
ᨮ묨 NULL.  ⠭ 0  NULL      ᠭ 
㭪樨 NVL   ⥪.   ⠪,   ᯮ ࠧ  
  ଠ ("$","9","0"  ".").



                                    -- 74 --



 뤠  ਥ  ࠡ  㤭  ⤥ 20  栬,  
뢮묨 ᫮,  ⠪  祭   , 室 :

SELECT ENAME, TO_CHAR(HIREDATE,'fmMonth DD, YYYY') HIREDATE
     FROM EMP
     WHERE DEPTNO = 20


ENAME         HIREDATE
------------  -----------------------
SMITH         December 17, 1980
JONES         April 2, 1981
SCOTT         February 15, 1988
ADAMS         March 20, 1988
FORD          December 3, 1981


        祭 ࠢ쭮 ଠ

 ଠ   ⠪ ᯮ짮     祭   
ଠ,    ORACLE.      ⠡ ORACLE 
  祭  ⨯ ,  ᮮ⢥騬 ⨯  
⮫殢. ਬ, ᫨  ⠢ ,  ORACLE     
 ᨬ  ப  ⠭⭮ ଠ  DD-MON-YY.  ᫨   
ᯮ ⠭ ଠ  ,  室 ᯮ짮 㭪樥 
TO_DATE  ᮮ⢥騬 ﬨ ଠ.

    㦠饣 JONES  20-May-88  ᯮ ⠭ 
ଠ, 室 :

UPDATE EMP
     SET HIREDATE = TO_DATE('88 08 20','YY MM DD')
     WHERE ENAME = 'JONES'


        㭪 TO_NUMBER

㭪 TO_NUMBER  ਭ  ଠ.   ᨬ ࠦ, 
ᯮ㥬  㭪樨 TO_NUMBER,  ਢ  ࠢ쭮  (. 
 5 "ࠢ筨  SQL - ࠬ").


        ᫮ ଠ

᫮ ଠ ᯮ ᮢ㯭   㭪樥  TO_CHAR  ॢ  
祭  ⨯  NUMBER  CHARACTER.   ᯮ짮 ⮫쪮  
㭪樥 TO_CHAR. ८ࠧ  NUMBER   CHARACTER  믮  
 뤠 , ⠪   ।  ⥬ ORACLE.

 ᫮ ଠ ਢ  㣫 ᫠   㪠 ⢠ 
 .

᫨ 祭       楫 ,  祬 ᯥ஢ 
 ଠ,   窠.

 ᫥饩 ⠡  ⨬ ᫮ ଠ:



                                    -- 75 --



      ਬ      ᠭ

9            9999        ᫮ "9" । ᫮ 뤠 権.
0            0999        뤠 騥 㫨.
$            $9999       । 祭  .
B            B9999       뤠 㫥 祭  ஡,    "0".
MI           9999MI      뤠 "-" ᫥ ⥫쭮 祭.
PR           9999PR      뤠 ⥫ 祭  <㣫 ᪮>.
      9,999       뤠   樨 .
窠        99.99       뤠   樨  .
V            999V99       祭  10*n,  n -
                         ⢮ ⮪ ᫥ "V".
E            9.999EEEE   뤠 १  筮 樨
                         (ଠ  ᮤঠ 筮 4 "")
DATE         DATE         , ࠭  ᫮ ଠ (ORACLE 
                         Version  2).  뤠    ଠ 'MM/DD/YY'.


        ଠ 

ଠ   ᯮ  㭪樨 TO_CHAR  뤠   ࠧ -
.  ஬ ⮣,  ᯮ 㭪樥 TO_DATE  । ORACLE 
祭,   ⠭⭮ ଠ. (⠭ ଠ :DD-MON-YY

 ᫥饩 ⠡ ਢ  ଠ⮢ :
              祭

SCC  CC           ; "S" 砥 ।७  
                     襩  ᨬ "-".
YYYY  SYYYY       ; "S" 砥 ।७   襩  
                     ᨬ "-".
YYY  YY  Y     ᫥ 3, 2    .
Y,YYY                  ⮩  㪠 樨
SYEAR  YEAR        ᫮; "S" 砥 㪠 "-", ᫨   ..
BC  AD            BC -  襩 , AD -  .
B.C.  A.D.         ,   窠  㪠 
Q                     ⠫ (1,2,3,4; ﭢ-=1)
MM                    (01-12; ﭢ=01)

MONTH                 ,  ஡  9 ᨬ.
MON                   , 㪢 ᮪饭
WW                     (1-52). ࢠ  -
                      ࢮ ᫠   த  ᥤ쬮.
W                      (1-5). ࢠ  -
                       ࢮ    த  ᥤ쬮.
DDD                    (1-366).
DD                     (1-31).
D                      (1-7).
DAY                    ,   9ᨬ ஡.
DY                    , 㪢 ॢ
J                    ᪠ ; ᫮ , 襤 
                     1 ﭢ 4712 .  ..
AM  PM             㤭  ᫥ 㤭.
A.M  P.M           ,   窠.
HH  HH12            (1-12).
HH24                   (0-24).
MI                    (0-59).
SS                   㭤 (0-59).

                                    -- 76 --



SSSSS                ⢮ ᥪ㭤, 襤  㭮.
/.,.                 㭪, ७  १.
"..."                稥, ७饥  १.


 ⠬ ଠ 㭪樨 TO_CHAR    䨪 FM (Fill Mode 
- ० ).   䨪  ஡,  ⠢塞   
᫥騥  (ਬ  -    MONTH),   ⠪    
᫥ ⮢ 騥 㫨 (ਬ -  MI). 㭪 TO_CHAR 
頥 १ ६ .

FM -  ࠬ ⨯ . ᫨   ଠ   ,   
᫥ ࢮ  ஡  稭 ,  ᫥ ண -  
⠢  १.

 ࢨ  ଠ 㭪樨 TO_CHAR     ᫥騥 
䨪:

TH          浪  (.. "DDTH"  "4TH").
SP           뤠 ᫮ (.. "DDSP"  "FOUR").
SPTH     浪  뤠 ᫮ (.. "DDSPTH"
    THSP     "FOURTH").

뤠 ஢ (᫮) ய묨    묨  㪢    
ॣ,    ஬ ࠥ ᮮ⢥騩  ଠ.  ਬ, 
"DAY" ਢ  뤠 ᮮ⢥饣 ᫮  ய묨 㪢 - "MONDAY";  
 "Day",   "Monday",   "day" - "monday".

஬ ⮣,   ଠ  ⠢ ࠧ  㭪樨, 
ਬ - ,  ᫥,  ,  ᨬ ⠭, 祭  
窨 (    !).    㭪樨    ᨬ  ⠭ 
७  १  . ਬ,  ଠ:

'DDTH "of" fmMonth, YYYY'

ਢ  뤠 ᫥饣 १:

15TH of March, 1989

   稥 䨪 "fm".  砥  ⢨  
  ஡  9 ᨬ:

15TH of March    , 1989

 祭      ଠ  ,    . ਬ 
᫥騩 :

SELECT TO_CHAR(sysdate, 'fmDay"''s Special"')

        뤠 ⠪ १:
Tuesday's Special








                                    -- 77 --




        ࠦ

ࠦ -       ᪮쪨 祭, 権  
㭪権,  ண  祭.  饬  砥  ⮢ 
ࠦ । । ⨯ .  ଠ쭮 । 
ࠦ  ORACLE ਢ  ᫥饬 ࠧ.

 ᫥饬 ⮬ ਬ ࠦ  祭 4  ⨯  NUMBER 
(      ⮢):

2*2

 ᫥饬  ᭮ ਬ ᯮ  樨, ⠪  㭪樨.
  ࠦ  ⥪饩   ᥬ ,  㬬 㤠 
६   १ ८ࠧ뢠  ⨯  CHAR.

TO_CHAR(TRUNC(SYSDATE+7))

ࠦ   ᯮ짮  ࠪ᪨ ,    ᯮ짮 
ﭭ 祭.  ਬ,   ⠢ ࠦ   ࠫ  
'smith'    ࠧ SET  UPDATE:

SET ENAME = 'smith'

 ਢ  ਬ   ப  'smith'   ࠦ 
LOWER(ENAME):

SET ENAME = LOWER(ENAME)






























                                    -- 78 --




        Expr

祭     ⮢ ப, ᫮,   ࠦ.
।뫪    .
⠪      ࠦ  :
ଠ I        ⮫殬, ⠭⮩  ᯥ樠 祭

               [table.] {column | ROWID }
               text
               number
               sequence.CURRVAL
               sequence.NEXTVAL
               NULL
               ROWNUM
               LEVEL
               SYSDATE
               UID
               USER

ਬ        EMP.ENAME
               'this is a text string'
               10
               SYSDATE

ଠ II       易 ६  易⥫쭮 ୮ ६

               : { n | variable } [:ind_variable ]

ਬ        :employee_name:employee_name_indicator_var
               :department_location

ଠ III      뫪  㭪 (㯭 㭪樨 뢠  ⮩ ).

               function_name ( [DISTINCT | ALL] expr [,expr]...)

ਬ        LENGTH('BLAKE')
               ROUND(1234.567*43)

ଠ IV         㣨  ࠦ  (᫥ ).

               (expr)
               +expr, -expr, PRIOR expr
               expr * expr, expr / expr
               expr + expr, expr - expr, expr || expr

ਬ        ('CLARK' || 'SMITH')
               LENGTH('MOOSE') * 57
               SQRT(114) + 72

ଠ V        ᮪ ࠦ, 祭  ᪮:

               (expr [,expr]...)

ਬ        (10, 20, 40)
               ('SCOTT', 'BLAKE', 'TAYLOR')
               (LENGTH('MOOSE') * 57, -SQRT(144) + 72, 69)


                                    -- 79 --



砭    ࠦ ᯮ :
ᯮ짮    * ᯨ᪥ 롮ન  SELECT
                 * ᫮  ࠧ WHERE  HAVING
                 * ࠧ CONNECT BY, START WITH, ORDER BY
                 * ࠧ VALUE  INSERT
                 * ࠧ SET  UPDATE

易       "㭪樨"  ⮩ ,  ⠪ ࠧ-
ࠧ         "Text", "Integer"  "Number"   3 ⮣ 㪮⢠.


        ᫮

᫮ -      ࠦ   ᪨ 権,   
१⮬  ன    祭 FALSE  TRUE.  ᫮  뫮 
  "᪨" ⨯ ,  ଠ쭮 ORACLE ⠪ ⨯  
ন. ᠭ ᨭ⠪  ᫮  ਢ    ᫥饬 ࠧ.

 ਬ ⮣ ᫮, १⮬ ண ᥣ 㤥 TRUE:
1 = 1

 ᫥饬 ਬ ਢ  ᫮ ᫮,  ஥ 롨ࠥ ROWID 
  ப, ८ࠧ  ⨯  CHAR,  楯  ப 
'THE ROWID'  १ ࠢ    ࠢ  ᨬ쭮 ⠭⮩ 
'smith':

ROWIDTOCHAR(ROWID) || 'THE ROWID' >= 'smith'

   ᪨  権    ꥤ ᪮쪮 ᫮  .  
ਬ,   ⮩ 楫   ᯮ짮  AND:

(1 = 1) AND (5 < 7)

   ஡ ଠ樨  ᫥ ᫮  ᪨ ﬨ 
  ࠧ ⮩  "᪨ 樨".

᫮   ᯮ  ࠧ WHERE ஢ DELETE,  SELECT 
 UPDATE.  ஬ ⮣,  ਬ  ࠧ START WITH, CONNECT BY  
HAVING  SELECT.


        Condition

祭       १⮬ TRUE  FALSE.
।뫪    .
⠪      ᫮  :
ଠ I        ࠢ  ࠦ  १⮬ .

               <expr> <comparsion operator> <expr>
               <expr> <comparsion operator> <query>
               <expr-list> <equal-or-not> <expr-list>
               <expr-list> <equal-or-not> <query>

ଠ II       ࠢ    ᥬ ⠬ ᯨ᪠ 





                                    -- 80 --



               <expr><comparsion>{ANY|ALL }(<expr>[,<expr>]...)
               <expr><comparsion>{ANY|ALL } <query>
               <expr-list><equal-or-not> {ANY | ALL}
                  (<expr-list> [,<expr-list>]...)
               <expr-list><equal-or-not> {ANY | ALL} <query>

ଠ III        稥  ᯨ᪥ 

               <expr> [NOT] IN (<expr> [,<expr>]...)
               <expr> [NOT] IN <query>
               <expr-list> [NOT] IN (<expr-list> [,<expr-list>]...)
               <expr-list> [NOT] IN <query>

ଠ IV         宦  

               <expr> [NOT] BETWEEN <expr> AND <expr>

ଠ V          祭 NULL

               <expr> IS [NOT] NULL

ଠ VI         ⢮   ப

               EXISTS <query>

ଠ VII       㣨 ᫮ (࠭ ᫥)

               ( <condition> )
               NOT <condition>
               <condition> AND <condition>
               <condition> OR <condition>

砭    ᯮ  ࠧ WHERE, START WITH,
ᯮ짮  CONNECT BY  HAVING.

ਬ        ENAME = 'SMITH'
               EMP.DEPTNO = DEPT.DEPTNO
               HIREDATE > '01-JAN-88'
               JOB IN ('PRESIDENT', 'CLERK', 'ANALYST')
               SAL BETWEEN 500 AND 1000
               COMM IS NULL AND SAL = 2000

易       SELECT,  INSERT,  UPDATE  DELETE 
ࠧ         5  "ࠢ筨    SQL  - ࠬ";
               ࠧ HAVING  WHERE   6 "ࠧ  -
                SELECT".













                                    -- 81 --




    5

       SQL - 

 ⮩  ᮤন ⠫쭮 ᠭ  SQL - ஢.  
訬 ᪫祭ﬨ       ᯮ짮   
த ORACLE.   뢠  䠢⭮ 浪;  ᠭ 
  砥  ᫥騥 ࠧ:

祭           뢠  ᯮ짮 
।뫪           ਢ,   室
                      믮 ⮣ .
⠪            뢠,     . ᯮ㥬
                      ᠭ  ।᫮   㬥.
祢 ᫮       뢠  㭪   祢
 ࠬ          ᫮  ࠬ.  祢 ᫮ -  ப,  
                        ⠪,   ( ਢ   
                     ᨬ 孥 ॣ). ࠬ - ப,  
                     ன 짮⥫ 頥 室  祭 
                     (ਢ  ᨬ  ॣ).

砭          㦤,    ࠧ    -
ᯮ짮          .
ਬ              ਢ ਬ  .
易 ࠧ      ࠧ   ⥫쭮 ଠ樥.


          SQL - ࠬ

 ਫ  "⠪ SQL"   ᢮  ᨭ⠪ SQL - -
஢.  ਢ  ⠡ ᢥ  SQL -    㭪樮 
祭.    ⠡ 뢠 ᫥騥 ⨯ SQL - ஢:

DDL       Data Defenition  Language  (  । -
          ):       ꥪ-
          ⮢       ᯮ ᫮ -
          .   ᫥ 믮  DDL - 
          ORACLE  믮  COMMIT.

DML       Data Manipulation  Language ( 樨 -
          묨):   믮 ࠧ -
          樨  묨 .

EMB       Embedded SQL (஥ SQL):  , ᯮ㥬  饭
          DDL  DML - ஢  ணࠬ   楤୮ 몥.  
          ஥  SQL ন   ᫥ ४஢ 
          ORACLE: Pro*Ada,  Pro*C,  Pro*COBOL,  Pro*FORTRAN, Pro*Pascal  
          Pro*PL/I.

              ?  ᠭ

/* ... */                        頥 ਩ 
                                   SQL -  ࠬ.
ALTER CLUSTER        DDL  Y      ८।    ࠬ
                                  .
ALTER DATABASE       DDL  Y      뢠 (뢠, ), p


                                    -- 82 --



                                  २뢠  䠩  ;  
                                 ४砥 ० 娢樨; 
                                 /⬥ 䠩 ୮ 믮

ALTER INDEX          DDL  Y      ८।      饥
                                 ।  
ALTER ROLLBACK       DDL  Y      ८।      饥
SEGMENT                          ।  ᥣ ⪠
ALTER SEQUENCE       DDL  Y      ८।    
                                 ᫥⥫ ஢.
ALTER SESSION        DDL  Y       ⥪騩 ᥠ 짮⥫.
ALTER TABLE          DDL          ⮫   ⠡-
                                 , ८।   -
                                  ⠡,  ⠪-
                                  -  饥 । .
ALTER TABLESPACE     DDL  Y      ॢ  ⠡筮 -
                                 ࠭⢮  off/online, -
                                  砫/砭
                                 backup,  /२-
                                 뢠 䠩  ,
                                 易  ⠡ -
                                 ࠭⢮,   ࠬ
                                 । .
ALTER USER           DDL  Y       ஫ 짮⥫,
                                 㬠稢      ⠡筮
                                 ࠭⢮  㬠稢
                                 ६ ⠡筮  -
                                 ࠭⢮.
AUDIT                DDL         砥 ॣ -
                                   㪠 ᠬ -
                                  .
CLOSE CURSOR         EMB         ᢮        ,
                                 ঠ ஬.
COMMENT              DDL             ᫮   
                                 ਨ  ⠡.
COMMIT               DML  Y       , ஢-
                                    砫   ࠭樨,
                                 ﭭ묨.
CONNECT              EMB         ᮥ   (砥)
                                 짮⥫   .
CREATE CLUSTER       DDL           ,   
                                  ᮤঠ     
                                  ⠡.
CREATE DATABASE      DDL  Y           -
                                 ⠢    ᯮ짮-
                                 .
CREATE DATABASE      DDL            ।
LINK                             짮⥫  㤠 -
                                  .
CREATE INDEX         DDL            ⠡.
CREATE ROLLBACK      DDL  Y        ⠡筮 -
SEGMENT                          ⢥ ᥣ ⪠.
CREATE  SEQUENCE      DDL  Y      ᫥⥫쭮
                                 ਣ  ஢
                                 ᭮ 祩.
CREATE SYNONYM       DDL          ᨭ  ⠡
                                  .
CREATE TABLE         DDL          ⠡  ।-

                                    -- 83 --



                                   ⮫  ।-
                                  .
CREATE TABLESPACE    DDL  Y            -
                                    ࠭ ⠡,
                                 ᮢ, ६ ᥣ-
                                 ⮢   ᥣ⮢  ⪠  
                                  室騥      
                                 䠩.

CREATE VIEW          DDL         ।     
                                  ᪮쪨 ⠡ 
                                 㣨 .

DECLARE CURSOR       EMB         । .
DECLARE DATABASE     EMB         ।     㤠
                                    뫮  -
                                 ᫥ SQL - .
DECLARE STATEMENT    EMB         ।  SQL -  -
                                   SQL - .
DESCRIBE             EMB         樠   ਯ
                                  ࠭  ᠭ host
                                 - ६.
DELETE               DML              ࠭
                                 ப  ⠡.
DROP object          DDL          , 
                                 , ,  ᥣ -
                                 ,   ᫥⥫쭮,
                                 ᨭ, ⠡   
                                   .
EXECUTE IMMEDIATE    EMB         ⠢   믮
                                 SQL - ,  ᮤঠ-
                                 騩 host - ६.
EXPLAIN PLAN              Y      뢠   믮
                                 SQL - .
FETCH                EMB         롨ࠥ   .
GRANT                DDL           짮⥫
                                  ,  砥 -
                                 ஫  ।⠢  -
                                 ⥫ ਢ -
                                  ORACLE.    ।⠢
                                 짮⥫ ਢ 
                                 ⠡,  ⠪ ਢ
                                 ᯮ짮 ᮢ ⠡-
                                 筮 ࠭⢠.
INSERT               DML           ⠡  -
                                   ப.
LOCK TABLE           DML          ⠡, ६
                                 ࠭稢      
                                 㣨 짮⥫.
NOAUDIT              DDL         ⬥ ॣ -
                                     筮,
                                   ।騩  -
                                  AUDIT  
                                 樨 ॣ樨.
OPEN cursor          EMB         ।  ࠭ ᠭ-
                                  .
PREPARE              EMB         믮 ࠧ    SQL   -
                                 .

                                    -- 84 --



RENAME               DDL           ⠡,  -
                                 ஢  ᨭ.
REVOKE               DDL         ⬥ ਢ  
                                   짮⥫᪨
                                 ਢ       
                                 ⠡栬.
ROLLBACK             DML  Y      ⪠뢠   ஢
                                   窥  ࠭-
                                    砫 ࠭樨.
SAVEPOINT            DML  Y      ⠭   ஫
                                 ,   ன ᫥-
                                 ⢨   㤥 믮
                                 ⪠.
SELECT               DML         믮  ; 롨ࠥ
                                 ப   ⮫   
                                  ᪮쪨 ⠡.
SET TRANSACTION      DDL  Y      稭  ᮣᮢ  
                                 ⥭ ࠭.
UPDATE               DML            ⠡.
VALIDATE INDEX       DDL         ஢ 楫⭮ -
                                 .
WHENEWER             EMB         ,     
                                 ࠡ뢠 訡     
                                 ।०.


/* ...*/ (SQL - ਩)                  

祭     ਨ ⠢  襣 
               SQL - ,  뢠  ﭨ
                 ࠡ.

।뫪    ; ਨ     SQL -
               .

⠪      /* text */

祢 ᫮ text            ப, ᮤঠ ⠥
 ࠬ                    ᨬ  ᨬ쭮 
                               樮 ⥬,    ..
                               ASCII  EBCDIC.

砭    ਨ   室    
ᯮ짮  SQL -    (""  砥 - 
               ᫮).
               /* 稭 ਩,   */  蠥.
               ਩  ࠭    
               ᫮ ப     稭  -
                । ப.  ᫥襬  -
               窮     ᨬ.

ਬ         騩 SQL -  砥  ᥡ -
               쪮 ਥ:

               SELECT ENAME, SAL+COMM COMP, JOB, LOC
               /* Select all employees whose compensation is
               greater then that Jones.  -   -
               ,     ௫   ॢ蠥   ௫

                                    -- 85 --



               㦠饣 Jones */
               FROM EMP, DEPT
                               /* DEPT is used to get depar-
                               tment name - DEPT ᯮ-
                                 祭  -
                                */
               WHERE EMP.DEPTNO = DEPT.DEPTNO
                 AND SAL + COMM >      /* :       */
                   (SELECT SAL+COMM    /* COMP=SAL+COMM    */
                    FROM EMP           /* ௫         */
                    WHERE ENAME='JONES') /*          */

易       COMMENT.
ࠧ
               












































                                    -- 86 --



ALTER CLUSTER                                 


祭     ८।   ࠪ⨪ 
                .

।뫪        楬 , 
                ਢ  DBA    ࠪ-
               ⨪  㦮 .

⠪      ALTER CLUSTER [user.]cluster
               [PCTUSED integer] [PCTFREE integer]
               [SIZE integer]
               [INITRANS integer] [MAXTRANS integer]
               [STORAGE storage]

祢 ᫮ user             짮⥫ - 
 ࠬ                    .
               cluster          .
               PCTUSED integer (    ࠬ
                                PCTUSED  ᠭ 
                                CREATE TABLE).
               PCTFREE integer (    ࠬ
                                PCTFREE  ᠭ 
                                CREATE TABLE).
               SIZE integer     ।, ᪮쪮 祩 -
                                 㤥   -
                                  ORACLE,  ।-
                                 .  ᠭ
                                ⮣ ࠬ   
                                 CREATE CLUSTER.
               INITRANS integer (    ࠬ
                                INITRANS  ᠭ 
                                 CREATE TABLE).
               MAXTRANS integer (    ࠬ
                                MAXTRANS  ᠭ 
                                 CREATE TABLE).
               STORAGE storage   (.    ᠭ  ࠧ
                                 STORAGE).

砭    ᯮ  ALTER CLASTER,  :
ᯮ짮
               *  PCTUSED  PCTFREE   -
                  
               *  SIZE    
               *            祭
                 INITRANS  MAXTRANS
               *  騥 । ,  -
                    ࠬ஢  PCTINCREASE,
               MAXEXTENTS, NEXT.

               ᯮ  ALTER CLUSTER,   :

               *  ⢮ ⮫殢    
                 
               *  ࠬ MINEXTENTS
               *     ࠬ ⭮⥫쭮 -
                 , 㦥 । 

                                    -- 87 --



               * 㤠  ⠡    (.  
                 DROP CLUSTER  DROP TABLESPACE)
               *    ⠡筮  ࠭⢮,  ஬
                 ਭ 

ਬ         ⮡    CUSTOMER 짮⥫
               SCOTT ⠪,  ⮡   饬  ᮤঠ  4
                    ORACLE (।-
                ࠧ      ORACLE   2  
               2/(SIZE 512)=4)   ⠭  MAXEXTENTS  
               25, :

               ALTER CLUSTER SCOTT.CUSTOMER
                   SIZE 512
                   STORAGE (MAXEXTENTS 25)

易       CREATE CLUSTER  CREATE TABLE, ࠧ
ࠧ        STORAGE.
               








































                                    -- 88 --



  ALTER DATABASE                                       


祭      饩     ᫥-
                ࠢ:

               * ஢    ( ࠧ塞 
               ᪫⥫쭮 ०)
               *     
               * २    ⬥  䠩  ୠ
               ୮ 믮
               * ᯥ஢,  䠩 ୠ 㤥 -
               娢஢ ,  ᫥⥫쭮, 㤥 
                ⠭ ⥫   㤥  -
               娢஢  ,  ,   ⮫쪮 
               ⠭ .

।뫪    ॡ ਢ DBA.

⠪      ALTER DATABASE [ database ]
                 {ADD LOGFILE  filespec  [,filespec ...]
                 |DROP LOGFILE 'filename' [,'filename'] ...]
                 |RENAME FILE 'filename' [,'filename'] ...
                 TO filename [,filename] ... ]
                 |ARCHIVELOG
                 |NOARCHIVELOG
                 |MOUNT [SHARED | EXCLUSIVE]
                                  
                 | DISMOUNT
                 |OPEN
                 | CLOSE [NORMAL | IMMEDIATE]}
                         

祢 ᫮ database        䨪     ,
 ࠬ                          ᮤঠ
                                8  ᨬ.  ᫨  -
                               ,       㤥
                                 祭 ࠬ
                               䠩   INIT.ORA  -  DB_NAME.
                                䨪   易
                                 ᯥ䨪樥  
                                SQL*Net.
               ADD LOGFILE     ᯥ䨪      
                               ଥ:
               'filename' [SIZE integer [K|M]] integer [REUSE]
                               㪠뢠 SIZE  . ᫨
                               integer 饭,  ।-
                                 ࠧ  䠩 ୠ 
                               500.  ᫨     "",
                               integer  㬭   1024,
                               ᫨ "" -  1048576.
               DROP LOGFILE     ⥪饣  䠩  ୠ,
               filename            ⬥.

               RENAME FILE     ᯥ  ஥  
               filename TO       䠩  .



                                    -- 89 --



               filename          䠩  -
                               ⢥⢮ ᮣ襭 -
                               襩 樮 ⥬.
























































                                    -- 90 --
