a little bit of tech, a little bit of green, to help tame the savage techmachine.
ORACLE函数大全

SQL中的单记录函数
1.ASCII
返回与指定的字符对应的十进制数;
SQL> select ascii('A') A,ascii('a') a,ascii('0') zero,ascii(' ') space from dual;

        A         A      ZERO     SPACE
--------- --------- --------- ---------
       65        97        48        32


2.CHR
给出整数,返回对应的字符;
SQL> select chr(54740) zhao,chr(65) chr65 from dual;

ZH C
-- -
赵 A

3.CONCAT
连接两个字符串;
SQL> select concat('010-','88888888')||'转23'  高乾竞电话 from dual;

高乾竞电话
----------------
010-88888888转23

4.INITCAP
返回字符串并将字符串的第一个字母变为大写;
SQL> select initcap('smith') upp from dual;

UPP
-----
Smith


5.INSTR(C1,C2,I,J)
在一个字符串中搜索指定的字符,返回发现指定的字符的位置;
C1    被搜索的字符串
C2    希望搜索的字符串
I     搜索的开始位置,默认为1
J     出现的位置,默认为1
SQL> select instr('oracle traning','ra',1,2) instring from dual;

 INSTRING
---------
        9


6.LENGTH
返回字符串的长度;
SQL> select name,length(name),addr,length(addr),sal,length(to_char(sal)) from gao.nchar_tst;

NAME   LENGTH(NAME) ADDR             LENGTH(ADDR)       SAL LENGTH(TO_CHAR(SAL))
------ ------------ ---------------- ------------ --------- --------------------
高乾竞            3 北京市海锭区                6   9999.99                    7

 

7.LOWER
返回字符串,并将所有的字符小写
SQL> select lower('AaBbCcDd')AaBbCcDd from dual;

AABBCCDD
--------
aabbccdd


8.UPPER
返回字符串,并将所有的字符大写
SQL> select upper('AaBbCcDd') upper from dual;

UPPER
--------
AABBCCDD

 

9.RPAD和LPAD(粘贴字符)
RPAD  在列的右边粘贴字符
LPAD  在列的左边粘贴字符
SQL> select lpad(rpad('gao',10,'*'),17,'*')from dual;

LPAD(RPAD('GAO',1
-----------------
*******gao*******
不够字符则用*来填满


10.LTRIM和RTRIM
LTRIM  删除左边出现的字符串
RTRIM  删除右边出现的字符串
SQL> select ltrim(rtrim('   gao qian jing   ',' '),' ') from dual;

LTRIM(RTRIM('
-------------
gao qian jing


11.SUBSTR(string,start,count)
取子字符串,从start开始,取count个
SQL> select substr('13088888888',3,8) from dual;

SUBSTR('
--------
08888888


12.REPLACE('string','s1','s2')
string   希望被替换的字符或变量
s1       被替换的字符串
s2       要替换的字符串
SQL> select replace('he love you','he','i') from dual;

REPLACE('H
----------
i love you


13.SOUNDEX
返回一个与给定的字符串读音相同的字符串
SQL> create table table1(xm varchar(8));
SQL> insert into table1 values('weather');
SQL> insert into table1 values('wether');
SQL> insert into table1 values('gao');

SQL> select xm from table1 where soundex(xm)=soundex('weather');

XM
--------
weather
wether


14.TRIM('s' from 'string')
LEADING   剪掉前面的字符
TRAILING  剪掉后面的字符
如果不指定,默认为空格符

15.ABS
返回指定值的绝对值
SQL> select abs(100),abs(-100) from dual;

 ABS(100) ABS(-100)
--------- ---------
      100       100


16.ACOS
给出反余弦的值
SQL> select acos(-1) from dual;

 ACOS(-1)
---------
3.1415927


17.ASIN
给出反正弦的值
SQL> select asin(0.5) from dual;

ASIN(0.5)
---------
.52359878


18.ATAN
返回一个数字的反正切值
SQL> select atan(1) from dual;

  ATAN(1)
---------
.78539816


19.CEIL
返回大于或等于给出数字的最小整数
SQL> select ceil(3.1415927) from dual;

CEIL(3.1415927)
---------------
              4


20.COS
返回一个给定数字的余弦
SQL> select cos(-3.1415927) from dual;

COS(-3.1415927)
---------------
             -1


21.COSH
返回一个数字反余弦值
SQL> select cosh(20) from dual;

 COSH(20)
---------
242582598


22.EXP
返回一个数字e的n次方根
SQL> select exp(2),exp(1) from dual;

   EXP(2)    EXP(1)
--------- ---------
7.3890561 2.7182818


23.FLOOR
对给定的数字取整数
SQL> select floor(2345.67) from dual;

FLOOR(2345.67)
--------------
          2345


24.LN
返回一个数字的对数值
SQL> select ln(1),ln(2),ln(2.7182818) from dual;

    LN(1)     LN(2) LN(2.7182818)
--------- --------- -------------
        0 .69314718     .99999999


25.LOG(n1,n2)
返回一个以n1为底n2的对数
SQL> select log(2,1),log(2,4) from dual;

 LOG(2,1)  LOG(2,4)
--------- ---------
        0         2


26.MOD(n1,n2)
返回一个n1除以n2的余数
SQL> select mod(10,3),mod(3,3),mod(2,3) from dual;

MOD(10,3)  MOD(3,3)  MOD(2,3)
--------- --------- ---------
        1         0         2


27.POWER
返回n1的n2次方根
SQL> select power(2,10),power(3,3) from dual;

POWER(2,10) POWER(3,3)
----------- ----------
       1024         27


28.ROUND和TRUNC
按照指定的精度进行舍入
SQL> select round(55.5),round(-55.4),trunc(55.5),trunc(-55.5) from dual;

ROUND(55.5) ROUND(-55.4) TRUNC(55.5) TRUNC(-55.5)
----------- ------------ ----------- ------------
         56          -55          55          -55


29.SIGN
取数字n的符号,大于0返回1,小于0返回-1,等于0返回0
SQL> select sign(123),sign(-100),sign(0) from dual;

SIGN(123) SIGN(-100)   SIGN(0)
--------- ---------- ---------
        1         -1         0


30.SIN
返回一个数字的正弦值
SQL> select sin(1.57079) from dual;

SIN(1.57079)
------------
           1


31.SIGH
返回双曲正弦的值
SQL> select sin(20),sinh(20) from dual;

  SIN(20)  SINH(20)
--------- ---------
.91294525 242582598


32.SQRT
返回数字n的根
SQL> select sqrt(64),sqrt(10) from dual;

 SQRT(64)  SQRT(10)
--------- ---------
        8 3.1622777


33.TAN
返回数字的正切值
SQL> select tan(20),tan(10) from dual;

  TAN(20)   TAN(10)
--------- ---------
2.2371609 .64836083


34.TANH
返回数字n的双曲正切值
SQL> select tanh(20),tan(20) from dual;

 TANH(20)   TAN(20)
--------- ---------
        1 2.2371609

 

35.TRUNC
按照指定的精度截取一个数
SQL> select trunc(124.1666,-2) trunc1,trunc(124.16666,2) from dual;

   TRUNC1 TRUNC(124.16666,2)
--------- ------------------
      100             124.16

 

36.ADD_MONTHS
增加或减去月份
SQL> select to_char(add_months(to_date('199912','yyyymm'),2),'yyyymm') from dual;

TO_CHA
------
200002
SQL> select to_char(add_months(to_date('199912','yyyymm'),-2),'yyyymm') from dual;

TO_CHA
------
199910


37.LAST_DAY
返回日期的最后一天
SQL> select to_char(sysdate,'yyyy.mm.dd'),to_char((sysdate)+1,'yyyy.mm.dd') from dual;

TO_CHAR(SY TO_CHAR((S
---------- ----------
2004.05.09 2004.05.10
SQL> select last_day(sysdate) from dual;

LAST_DAY(S
----------
31-5月 -04


38.MONTHS_BETWEEN(date2,date1)
给出date2-date1的月份
SQL> select months_between('19-12月-1999','19-3月-1999') mon_between from dual;

MON_BETWEEN
-----------
          9
SQL>selectmonths_between(to_date('2000.05.20','yyyy.mm.dd'),to_date('2005.05.20','yyyy.mm.dd')) mon_betw from dual;

 MON_BETW
---------
      -60


39.NEW_TIME(date,'this','that')
给出在this时区=other时区的日期和时间
SQL> select to_char(sysdate,'yyyy.mm.dd hh24:mi:ss') bj_time,to_char(new_time
  2  (sysdate,'PDT','GMT'),'yyyy.mm.dd hh24:mi:ss') los_angles from dual;

BJ_TIME             LOS_ANGLES
------------------- -------------------
2004.05.09 11:05:32 2004.05.09 18:05:32


40.NEXT_DAY(date,'day')
给出日期date和星期x之后计算下一个星期的日期
SQL> select next_day('18-5月-2001','星期五') next_day from dual;

NEXT_DAY
----------
25-5月 -01

 

41.SYSDATE
用来得到系统的当前日期
SQL> select to_char(sysdate,'dd-mm-yyyy day') from dual;

TO_CHAR(SYSDATE,'
-----------------
09-05-2004 星期日
trunc(date,fmt)按照给出的要求将日期截断,如果fmt='mi'表示保留分,截断秒
SQL> select to_char(trunc(sysdate,'hh'),'yyyy.mm.dd hh24:mi:ss') hh,
  2  to_char(trunc(sysdate,'mi'),'yyyy.mm.dd hh24:mi:ss') hhmm from dual;

HH                  HHMM
------------------- -------------------
2004.05.09 11:00:00 2004.05.09 11:17:00

 

42.CHARTOROWID
将字符数据类型转换为ROWID类型
SQL> select rowid,rowidtochar(rowid),ename from scott.emp;

ROWID              ROWIDTOCHAR(ROWID) ENAME
------------------ ------------------ ----------
AAAAfKAACAAAAEqAAA AAAAfKAACAAAAEqAAA SMITH
AAAAfKAACAAAAEqAAB AAAAfKAACAAAAEqAAB ALLEN
AAAAfKAACAAAAEqAAC AAAAfKAACAAAAEqAAC WARD
AAAAfKAACAAAAEqAAD AAAAfKAACAAAAEqAAD JONES


43.CONVERT(c,dset,sset)
将源字符串 sset从一个语言字符集转换到另一个目的dset字符集
SQL> select convert('strutz','we8hp','f7dec') "conversion" from dual;

conver
------
strutz


44.HEXTORAW
将一个十六进制构成的字符串转换为二进制


45.RAWTOHEXT
将一个二进制构成的字符串转换为十六进制

 

46.ROWIDTOCHAR
将ROWID数据类型转换为字符类型

 

47.TO_CHAR(date,'format')
SQL> select to_char(sysdate,'yyyy/mm/dd hh24:mi:ss') from dual;

TO_CHAR(SYSDATE,'YY
-------------------
2004/05/09 21:14:41

 

48.TO_DATE(string,'format')
将字符串转化为ORACLE中的一个日期


49.TO_MULTI_BYTE
将字符串中的单字节字符转化为多字节字符
SQL>  select to_multi_byte('高') from dual;

TO
--


50.TO_NUMBER
将给出的字符转换为数字
SQL> select to_number('1999') year from dual;

     YEAR
---------
     1999


51.BFILENAME(dir,file)
指定一个外部二进制文件
SQL>insert into file_tb1 values(bfilename('lob_dir1','image1.gif'));


52.CONVERT('x','desc','source')
将x字段或变量的源source转换为desc
SQL> select sid,serial#,username,decode(command,
  2  0,'none',
  3  2,'insert',
  4  3,
  5  'select',
  6  6,'update',
  7  7,'delete',
  8  8,'drop',
  9  'other') cmd  from v$session where type!='background';

      SID   SERIAL# USERNAME                       CMD
--------- --------- ------------------------------ ------
        1         1                                none
        2         1                                none
        3         1                                none
        4         1                                none
        5         1                                none
        6         1                                none
        7      1275                                none
        8      1275                                none
        9        20 GAO                            select
       10        40 GAO                            none


53.DUMP(s,fmt,start,length)
DUMP函数以fmt指定的内部数字格式返回一个VARCHAR2类型的值
SQL> col global_name for a30
SQL> col dump_string for a50
SQL> set lin 200
SQL> select global_name,dump(global_name,1017,8,5) dump_string from global_name;

GLOBAL_NAME                    DUMP_STRING
------------------------------ --------------------------------------------------
ORACLE.WORLD                   Typ=1 Len=12 CharacterSet=ZHS16GBK: W,O,R,L,D


54.EMPTY_BLOB()和EMPTY_CLOB()
这两个函数都是用来对大数据类型字段进行初始化操作的函数


55.GREATEST
返回一组表达式中的最大值,即比较字符的编码大小.
SQL> select greatest('AA','AB','AC') from dual;

GR
--
AC
SQL> select greatest('啊','安','天') from dual;

GR
--


56.LEAST
返回一组表达式中的最小值
SQL> select least('啊','安','天') from dual;

LE
--


57.UID
返回标识当前用户的唯一整数
SQL> show user
USER 为"GAO"
SQL> select username,user_id from dba_users where user_id=uid;

USERNAME                         USER_ID
------------------------------ ---------
GAO                                   25

 

58.USER
返回当前用户的名字
SQL> select user from  dual;

USER
------------------------------
GAO


59.USEREVN
返回当前用户环境的信息,opt可以是:
ENTRYID,SESSIONID,TERMINAL,ISDBA,LABLE,LANGUAGE,CLIENT_INFO,LANG,VSIZE
ISDBA  查看当前用户是否是DBA如果是则返回true
SQL> select userenv('isdba') from dual;

USEREN
------
FALSE
SQL> select userenv('isdba') from dual;

USEREN
------
TRUE
SESSION
返回会话标志
SQL> select userenv('sessionid') from dual;

USERENV('SESSIONID')
--------------------
                 152
ENTRYID
返回会话人口标志
SQL> select userenv('entryid') from dual;

USERENV('ENTRYID')
------------------
                 0
INSTANCE
返回当前INSTANCE的标志
SQL> select userenv('instance') from dual;

USERENV('INSTANCE')
-------------------
                  1
LANGUAGE
返回当前环境变量
SQL> select userenv('language') from dual;

USERENV('LANGUAGE')
----------------------------------------------------
SIMPLIFIED CHINESE_CHINA.ZHS16GBK
LANG
返回当前环境的语言的缩写
SQL> select userenv('lang') from dual;

USERENV('LANG')
----------------------------------------------------
ZHS
TERMINAL
返回用户的终端或机器的标志
SQL> select userenv('terminal') from dual;

USERENV('TERMINA
----------------
GAO
VSIZE(X)
返回X的大小(字节)数
SQL> select vsize(user),user from dual;

VSIZE(USER) USER
----------- ------------------------------
          6 SYSTEM

 

60.AVG(DISTINCT|ALL)
all表示对所有的值求平均值,distinct只对不同的值求平均值
SQLWKS> create table table3(xm varchar(8),sal number(7,2));
语句已处理。
SQLWKS>  insert into table3 values('gao',1111.11);
SQLWKS>  insert into table3 values('gao',1111.11);
SQLWKS>  insert into table3 values('zhu',5555.55);
SQLWKS> commit;

SQL> select avg(distinct sal) from gao.table3;

AVG(DISTINCTSAL)
----------------
         3333.33

SQL> select avg(all sal) from gao.table3;

AVG(ALLSAL)
-----------
    2592.59


61.MAX(DISTINCT|ALL)
求最大值,ALL表示对所有的值求最大值,DISTINCT表示对不同的值求最大值,相同的只取一次
SQL> select max(distinct sal) from scott.emp;

MAX(DISTINCTSAL)
----------------
            5000


62.MIN(DISTINCT|ALL)
求最小值,ALL表示对所有的值求最小值,DISTINCT表示对不同的值求最小值,相同的只取一次
SQL> select min(all sal) from gao.table3;

MIN(ALLSAL)
-----------
    1111.11


63.STDDEV(distinct|all)
求标准差,ALL表示对所有的值求标准差,DISTINCT表示只对不同的值求标准差
SQL> select stddev(sal) from scott.emp;

STDDEV(SAL)
-----------
  1182.5032

SQL> select stddev(distinct sal) from scott.emp;

STDDEV(DISTINCTSAL)
-------------------
           1229.951

 

64.VARIANCE(DISTINCT|ALL)
求协方差

SQL> select variance(sal) from scott.emp;

VARIANCE(SAL)
-------------
    1398313.9


65.GROUP BY
主要用来对一组数进行统计
SQL> select deptno,count(*),sum(sal) from scott.emp group by deptno;

   DEPTNO  COUNT(*)  SUM(SAL)
--------- --------- ---------
       10         3      8750
       20         5     10875
       30         6      9400

 

66.HAVING
对分组统计再加限制条件
SQL> select deptno,count(*),sum(sal) from scott.emp group by deptno having count(*)>=5;

   DEPTNO  COUNT(*)  SUM(SAL)
--------- --------- ---------
       20         5     10875
       30         6      9400
SQL> select deptno,count(*),sum(sal) from scott.emp having count(*)>=5 group by deptno ;

   DEPTNO  COUNT(*)  SUM(SAL)
--------- --------- ---------
       20         5     10875
       30         6      9400


67.ORDER BY
用于对查询到的结果进行排序输出
SQL> select deptno,ename,sal from scott.emp order by deptno,sal desc;

   DEPTNO ENAME            SAL
--------- ---------- ---------
       10 KING            5000
       10 CLARK           2450
       10 MILLER          1300
       20 SCOTT           3000
       20 FORD            3000
       20 JONES           2975
       20 ADAMS           1100
       20 SMITH            800
       30 BLAKE           2850
       30 ALLEN           1600
       30 TURNER          1500
       30 WARD            1250
       30 MARTIN          1250
       30 JAMES            950

Oracle 最常用功能函数经典汇总
来源:ChinaITLab 收集整理
2004-6-14 10:58:00
  * SQL Group Function
*
s (num can be a column or ex

pression)          

  (null values are ign
*
ored, default between distin

ct and all is all)      

  ********************
***************
****************************

****************

  AVG([distinct or all] num)   
-- average value
  COUNT(distinct or all] num)  
-- number of values
  MAX([distinct or all
] num)   -- maximum value

  MAX([distinct or all] num)   
-- minimum value
  STDDEV([distinct or
all] num)  -- standard devi
ation
  SUM([distinct or all
] num)   -- sum of values

  VARIANCE([distinct o
r all] num) -- variance of v
alues
                                                                               
  ********************************
***********************
************************

  * Miscellaneaous Functions :  
*
                       

  ********************
***************
****************************

****************

  DECODE(expr, srch1,
return1 [,srch2, return2...]
, default]
      -- if no search matches t
he expression then the default is returned,
      -- otherwise,
the first search that match
es will cause
      -- the corres
ponding return value to be r
eturned
  DUMP(column_name [,fmt [,start_p
os [, length]]])
     -- returns an
column
internal oracle format, used

for getting info about a

     -- format options : 8 = oc
tal, 10 = decimel, 16 = hex, 17 = characters
     -- return type
codes : 1 = varchar2, 2 = n
umber, 8 = long, 12 = date,
     --  23 = raw,
24 = long raw, 69 = rowid,
96 = char, 106 = mlslabel
  GREATEST(expr [,expr2 [, expr3...]]       
     -- returns the largest val
ue of all expressions
  LEAST(expr [,expr2 [, expr3...]]             
     -- returns the
smallest value of all expre
ssions
  NVL(expr1 ,expr2                                             
     -- if expr1 is not null, i
t is returned, otherwise expr2 is returned
  SQLCODE                                                               
     -- returns sql error code
query,
of last error. Can not be used directly in

     -- value must
be set to local variable fir
st
  SQLERRM                                                               
     -- returns sql
in query,
error message of last error

. Can not be used directly

     -- value must be set to lo
cal variable first
  UID                                                                       
     -- returns the user id of
the user you are logged on as
     -- useful in s
electing information from lo
w level sys tables
  USER                                                                     
     -- returns the
user name of the user you a
re logged on as
  USERENV('option')                                           
     -- returns inf
ormation about the user you
are logged on as
     -- options : E
NTRYID, SESSIONID, TERMINAL,
LANGUAGE, LABEL, OSDBA
     --      (
all options not available in
all Oracle versions)
  VSIZE(expr)                                                       
     -- returns the number of b
ytes used by the expression
     -- useful in s
electing information about t
able space requirements
                                                                               
  ********************
***************
****************************

****************

  * SQL Date Functions (dt represe
*
nts oracle date and time)          

  * (functions return
*
an oracle date unless otherw

ise specified)        

  ********************************
***********************
************************

  ADD_MONTHS(dt, num)
   -- adds num months to
dt (num can be negative)
  LAST_DAY(dt)    
   -- last day of month in
month containing dt
  MONTHS_BETWEEN(dt1, dt2) -- retu
dt2
rns fractional value of months between dt1,

  NEW_TIME(dt, tz1, tz
zone 2
2)  -- dt = date in time zo

ne 1, returns date in time

  NEXT_DAY(dt, str)    -- date
etc..)
of first (str) after dt (str = 'Monday',

  SYSDATE         -- present system date
  ROUND(dt [,fmt]     -- roun
ds dt as specified by format fmt
  TRUNC(dt [,fmt]  
   -- truncates dt as spe
cified by format fmt
                                                                               
  ********************************
***********************
************************

  * Number Functions :      
*
                       

  ********************************
***********************
************************

  ABS(num)       -- absolute
value of num
  CEIL(num)      -- smallest integer > or = num

  COS(num)       -- cosine(n
um), num in radians

  COSH(num)     
 -- hyperbolic cosine(num)
  EXP(num)      
-- e raised to the num powe
r
  FLOOR(num)      -- largest
integer < or = num
  LN(num)       -- natural
logarithm of num
  LOG(num2, num1)   -- logarith
m base num2 of num1
  MOD(num2, num1)   -- remainde
r of num2 / num1
  POWER(num2, num1) 
 -- num2 raised to the num1
power
  ROUND(num1 [,num2]  -- num1 rou
nded to num2 decimel places (default 0)
  SIGN(num)      -- sign of
num * 1, 0 if num = 0
  SIN(num)      
-- sin(num), num in radians

  SINH(num)      -- hyperbolic sine(num)
  SQRT(num)      -- square root of num     
  TAN(num)       -- tangent(
num), num in radians
  TANH(num)     
 -- hyperbolic tangent(num)

  TRUNC(num1 [,num2]  -- truncate
num1 to num2 decimel places (default 0)
                                                                               
  ********************************
***********************
************************

  * String Functions,
*
String Result :      

               

  ********************************
***********************
************************

  (num)          -- ASCII
character for num
  CHR(num)      
  -- ASCII character for n
um
  CONCAT(str1, str2)   -- str1
concatenated with str2 (same as str1||str2)
  INITCAP(str)    
  -- capitalize first lett
er of each word in str
  LOWER(str)       -- str w
ith all letters in lowercase
  LPAD(str1, num [,str2]) -- left
spaces)
pad str1 to length num with str2 (default

  LTRIM(str [,set]) 
   -- remove set from left
side of str (default spaces)
  NLS_INITCAP(str [,nl
s_val]) -- same as initcap f
or different languages
  NLS_LOWER(str [,nls_
val])  -- same as lower for
different languages
  REPLACE(str1, str2 [,str3]) -- r
eplaces str2 with str3 in str1
                 --
deletes str2 from str1 if str3 is omitted
  RPAD(str1, num [,str
(default spaces)
2])   -- right pad str1 to

length num with str2

  RTRIM(str [,set]) 
spaces)
     -- remove set from

right side of str (default

  SOUNDEX(str)    
    -- phonetic represen
tation of str
  SUBSTR(str, num2 [,n
um1])  -- substring of str,
starting with num2,
                 --
omitted)
num1 characters (to end of str if num1 is

  SUBSTRB(str, num2 [,
bytes
num1]) -- same as substr bu

t num1, num2 expressed in

  TRANSLATE(str, set1,
set2) -- replaces set1 in
str with set2
                 --
truncated
if set2 is longer than set1, it will be

  UPPER(str)     
    -- str with all lett
ers in uppercase
                                                                               
  ********************
***************
****************************

****************

  * String Functions,
*
Numeric Result :      

               

  ********************************
***********************
************************

                                                                               
  ASCII(str)           
 -- ASCII value of str
  INSTR(str1, str2 [,num1 [,num2]]
) -- position of num2th occurrence of
                  
  -- str2 in str1, starting at num1
                  
  -- (num1, num2 default to 1)
  INSTRB(str1, str2 [,num1 [num2]]

) -- same as instr, byte values for num1, num2

  LENGTH(str)    
        -- number of
characters in str
  LENGTHB(str)          
 -- number of bytes in str
  NLSSORT(str [,nls_val])    
  -- nls_val byte value of str
                                                                               
  ********************************
***********************
************************

  * SQL Conversion Functions   
*
                       

  ********************************
***********************
************************

  CHARTOROWID(str)        
  -- converts str to ROWID
  CONVERT(str, chr_set2 [,chr_set1
]) -- converts str to chr_set2
            
character set
        -- chr_set1

default is the datbase

  HEXTORAW(str)   
  -- converts hex string va
lue to internal raw values
  RAWTOHEX(raw_val)   -- convert
s raw hex value to hex string value
  ROWIDTOCHAR(rowid) 
 -- converts rowid to 18 ch
aracter string format
  TO_CHAR(expr [,fmt])
fmt
 -- converts expr(date or n

umber) to format specified by

  TO_DATE(str [,fmt])
  -- converts string to dat
e
  TO_MULTI_BYTE(str)  -- convert
s single byte string to multi byte string
  TO_NUMBER(str [,fmt]) -- convert
s str to a number formatted by fmt
  TO_SINGLE_BYTE(str)
  -- converts multi byte st
ring to single byte string
                                                                               
  ********************************
***********************
************************

  * SQL Date Formats 
*
              

               

  ********************
***************
****************************

****************

                                                                               
  BC, B.C.    BC indicator                             
  AD, A.D.    AD indicator                             
  CC, SCC     Cent
ury Code (SCC includes space
or - sign)
  YYYY, SYYYY   4 digit year (SY
YYY includes space or - sign)
  IYYY      4 digit ISO year                         
  Y,YYY      4 digit year with comma         
  YYY, YY, or Y  last 3, 2, or 1
digit of year
  YEAR, SYEAR   year spelled out
(SYEAR includes space or - sign)
  RR       last 2 digits of
year in prior or next century
  Q        quarter or year, 1 to 4             
  MM       month - from 01 to 12                 
  MONTH      month spelled out                     
  MON       month 3 letter abbreviation   
  RM       roman numeral for month             
  WW       week of year, 1 to 53                 
  IW       ISO week of year
, 1 to 52 or 1 to 53
  W        week of month, 1
to 5 (week 1 begins 1st day of the month)
  D        day of week, 1 to 7                     
  DD       day of month, 1 to 31                 
  DDD       day of year, 1 to 366               
  DAY       day of week spel
led out, nine characters right padded
  DY       day abbreviation                           

  J        # of
days since Jan 1, 4712 BC
  HH, HH12    hour of day, 1 to 12             
  HH24      hour of day, 0 to 23                 
  MI       minute of hour, 0 to 59             
  SS       second of minute, 0 to 59         
  SSSSS      seco
nds past midnight, 0 to 8639
9
  AM, A.M.    am indicator                             
  PM, P.M.    pm indicator                             
  any puctuation punc
tuation between format items
, as in 'DD/MM/YY'
  any text    text between format items   
  TH       conv
erts 1 to '1st', 2 to '2nd',
and so on
  SP       converts 1 to 'o
ne', 2 to 'two', and so on
  SPTH      converts 1 to 'F
IRST', 2 to 'SECOND', and so on
  FX       fill
exact : uses exact pattern
matching
  FM       fill mode : tog
gles suppression of blanks in output

posted on 2004-10-08 09:39  xyublog  阅读(1844)  评论(0编辑  收藏  举报