蒙在股里 发表于 2015-1-16 22:41:06

MYSQL网页设计ORACLE函数年夜全

你碰到的问题可能已经在社区中被别的人已经问过,即使没有MySQL学习教程,你也可以提出问题或通过Google来搜索答案。社区的相关负责人士:“MySQL社区是活跃、友好和内容渊博的。”oracle|函数SQL中的单纪录函数
1.ASCII
前往与指定的字符对应的十进制数;
SQL>selectascii(A)A,ascii(a)a,ascii(0)zero,ascii()spacefromdual;
AAZEROSPACE
------------------------------------
65974832


2.CHR
给出整数,前往对应的字符;
SQL>selectchr(54740)zhao,chr(65)chr65fromdual;

ZHC
---
赵A

3.CONCAT
毗连两个字符串;
SQL>selectconcat(010-,88888888)||转23高乾竞德律风fromdual;

高乾竞德律风
----------------
010-88888888转23

4.INITCAP
前往字符串并将字符串的第一个字母变成年夜写;
SQL>selectinitcap(smith)uppfromdual;

UPP
-----
Smith


5.INSTR(C1,C2,I,J)
在一个字符串中搜刮指定的字符,前往发明指定的字符的地位;
C1被搜刮的字符串
C2但愿搜刮的字符串
I搜刮的入手下手地位,默许为1
J呈现的地位,默许为1
SQL>selectinstr(oracletraning,ra,1,2)instringfromdual;

INSTRING
---------
9


6.LENGTH
前往字符串的长度;
SQL>selectname,length(name),addr,length(addr),sal,length(to_char(sal))fromgao.nchar_tst;

NAMELENGTH(NAME)ADDRLENGTH(ADDR)SALLENGTH(TO_CHAR(SAL))
---------------------------------------------------------------------------
高乾竞3北京市海锭区69999.997



7.LOWER
前往字符串,并将一切的字符小写
SQL>selectlower(AaBbCcDd)AaBbCcDdfromdual;

AABBCCDD
--------
aabbccdd


8.UPPER
前往字符串,并将一切的字符年夜写
SQL>selectupper(AaBbCcDd)upperfromdual;

UPPER
--------
AABBCCDD



9.RPAD和LPAD(粘贴字符)
RPAD在列的右侧粘贴字符
LPAD在列的右边粘贴字符
SQL>selectlpad(rpad(gao,10,*),17,*)fromdual;

LPAD(RPAD(GAO,1
-----------------
*******gao*******
不敷字符则用*来填满


10.LTRIM和RTRIM
LTRIM删除右边呈现的字符串
RTRIM删除右侧呈现的字符串
SQL>selectltrim(rtrim(gaoqianjing,),)fromdual;

LTRIM(RTRIM(
-------------
gaoqianjing


11.SUBSTR(string,start,count)
取子字符串,从start入手下手,取count个
SQL>selectsubstr(13088888888,3,8)fromdual;

SUBSTR(
--------
08888888


12.REPLACE(string,s1,s2)
string但愿被交换的字符或变量
s1被交换的字符串
s2要交换的字符串
SQL>selectreplace(heloveyou,he,i)fromdual;

REPLACE(H
----------
iloveyou


13.SOUNDEX
前往一个与给定的字符串读音不异的字符串
SQL>createtabletable1(xmvarchar(8));
SQL>insertintotable1values(weather);
SQL>insertintotable1values(wether);
SQL>insertintotable1values(gao);

SQL>selectxmfromtable1wheresoundex(xm)=soundex(weather);

XM
--------
weather
wether


14.TRIM(sfromstring)
LEADING剪失落后面的字符
TRAILING剪失落前面的字符
假如不指定,默许为空格符

15.ABS
前往指定值的相对值
SQL>selectabs(100),abs(-100)fromdual;

ABS(100)ABS(-100)
------------------
100100


16.ACOS
给出反余弦的值
SQL>selectacos(-1)fromdual;

ACOS(-1)
---------
3.1415927


17.ASIN
给出归正弦的值
SQL>selectasin(0.5)fromdual;

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


18.ATAN
前往一个数字的归正切值
SQL>selectatan(1)fromdual;

ATAN(1)
---------
.78539816


19.CEIL
前往年夜于或即是给出数字的最小整数
SQL>selectceil(3.1415927)fromdual;

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


20.COS
前往一个给定命字的余弦
SQL>selectcos(-3.1415927)fromdual;

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


21.COSH
前往一个数字反余弦值
SQL>selectcosh(20)fromdual;

COSH(20)
---------
242582598


22.EXP
前往一个数字e的n次方根
SQL>selectexp(2),exp(1)fromdual;

EXP(2)EXP(1)
------------------
7.38905612.7182818


23.FLOOR
对给定的数字取整数
SQL>selectfloor(2345.67)fromdual;

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


24.LN
前往一个数字的对数值
SQL>selectln(1),ln(2),ln(2.7182818)fromdual;

LN(1)LN(2)LN(2.7182818)
-------------------------------
0.69314718.99999999


25.LOG(n1,n2)
前往一个以n1为底n2的对数
SQL>selectlog(2,1),log(2,4)fromdual;

LOG(2,1)LOG(2,4)
------------------
02


26.MOD(n1,n2)
前往一个n1除以n2的余数
SQL>selectmod(10,3),mod(3,3),mod(2,3)fromdual;

MOD(10,3)MOD(3,3)MOD(2,3)
---------------------------
102


27.POWER
前往n1的n2次方根
SQL>selectpower(2,10),power(3,3)fromdual;

POWER(2,10)POWER(3,3)
---------------------
102427


28.ROUND和TRUNC
依照指定的精度举行舍进
SQL>selectround(55.5),round(-55.4),trunc(55.5),trunc(-55.5)fromdual;

ROUND(55.5)ROUND(-55.4)TRUNC(55.5)TRUNC(-55.5)
----------------------------------------------
56-5555-55


29.SIGN
取数字n的标记,年夜于0前往1,小于0前往-1,即是0前往0
SQL>selectsign(123),sign(-100),sign(0)fromdual;

SIGN(123)SIGN(-100)SIGN(0)
----------------------------
1-10


30.SIN
前往一个数字的正弦值
SQL>selectsin(1.57079)fromdual;

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


31.SIGH
前往双曲正弦的值
SQL>selectsin(20),sinh(20)fromdual;

SIN(20)SINH(20)
------------------
.91294525242582598


32.SQRT
前往数字n的根
SQL>selectsqrt(64),sqrt(10)fromdual;

SQRT(64)SQRT(10)
------------------
83.1622777


33.TAN
前往数字的正切值
SQL>selecttan(20),tan(10)fromdual;

TAN(20)TAN(10)
------------------
2.2371609.64836083


34.TANH
前往数字n的双曲正切值
SQL>selecttanh(20),tan(20)fromdual;

TANH(20)TAN(20)
------------------
12.2371609



35.TRUNC
依照指定的精度截取一个数
SQL>selecttrunc(124.1666,-2)trunc1,trunc(124.16666,2)fromdual;

TRUNC1TRUNC(124.16666,2)
---------------------------
100124.16



36.ADD_MONTHS
增添或减往月份
SQL>selectto_char(add_months(to_date(199912,yyyymm),2),yyyymm)fromdual;

TO_CHA
------
200002
SQL>selectto_char(add_months(to_date(199912,yyyymm),-2),yyyymm)fromdual;

TO_CHA
------
199910


37.LAST_DAY
前往日期的最初一天
SQL>selectto_char(sysdate,yyyy.mm.dd),to_char((sysdate)+1,yyyy.mm.dd)fromdual;

TO_CHAR(SYTO_CHAR((S
--------------------
2004.05.092004.05.10
SQL>selectlast_day(sysdate)fromdual;

LAST_DAY(S
----------
31-5月-04


38.MONTHS_BETWEEN(date2,date1)
给出date2-date1的月份
SQL>selectmonths_between(19-12月-1999,19-3月-1999)mon_betweenfromdual;

MON_BETWEEN
-----------
9
SQL>selectmonths_between(to_date(2000.05.20,yyyy.mm.dd),to_date(2005.05.20,yyyy.mm.dd))mon_betwfromdual;

MON_BETW
---------
-60


39.NEW_TIME(date,this,that)
给出在this时区=other时区的日期和工夫
SQL>selectto_char(sysdate,yyyy.mm.ddhh24:mi:ss)bj_time,to_char(new_time
2(sysdate,PDT,GMT),yyyy.mm.ddhh24:mi:ss)los_anglesfromdual;

BJ_TIMELOS_ANGLES
--------------------------------------
2004.05.0911:05:322004.05.0918:05:32


40.NEXT_DAY(date,day)
给出日期date和礼拜x以后盘算下一个礼拜的日期
SQL>selectnext_day(18-5月-2001,礼拜五)next_dayfromdual;

NEXT_DAY
----------
25-5月-01



41.SYSDATE
用来失掉体系确当前日期
SQL>selectto_char(sysdate,dd-mm-yyyyday)fromdual;

TO_CHAR(SYSDATE,
-----------------
09-05-2004日曜日
trunc(date,fmt)依照给出的请求将日期截断,假如fmt=mi暗示保存分,截断秒
SQL>selectto_char(trunc(sysdate,hh),yyyy.mm.ddhh24:mi:ss)hh,
2to_char(trunc(sysdate,mi),yyyy.mm.ddhh24:mi:ss)hhmmfromdual;

HHHHMM
--------------------------------------
2004.05.0911:00:002004.05.0911:17:00



42.CHARTOROWID
将字符数据范例转换为ROWID范例
SQL>selectrowid,rowidtochar(rowid),enamefromscott.emp;

ROWIDROWIDTOCHAR(ROWID)ENAME
----------------------------------------------
AAAAfKAACAAAAEqAAAAAAAfKAACAAAAEqAAASMITH
AAAAfKAACAAAAEqAABAAAAfKAACAAAAEqAABALLEN
AAAAfKAACAAAAEqAACAAAAfKAACAAAAEqAACWARD
AAAAfKAACAAAAEqAADAAAAfKAACAAAAEqAADJONES


43.CONVERT(c,dset,sset)
将源字符串sset从一个言语字符集转换到另外一个目标dset字符集
SQL>selectconvert(strutz,we8hp,f7dec)"conversion"fromdual;

conver
------
strutz


44.HEXTORAW
将一个十六进制组成的字符串转换为二进制


45.RAWTOHEXT
将一个二进制组成的字符串转换为十六进制



46.ROWIDTOCHAR
将ROWID数据范例转换为字符范例



47.TO_CHAR(date,format)
SQL>selectto_char(sysdate,yyyy/mm/ddhh24:mi:ss)fromdual;

TO_CHAR(SYSDATE,YY
-------------------
2004/05/0921:14:41



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>selectto_multi_byte(高)fromdual;

TO
--



50.TO_NUMBER
将给出的字符转换为数字
SQL>selectto_number(1999)yearfromdual;

YEAR
---------
1999


51.BFILENAME(dir,file)
指定一个内部二进制文件
SQL>insertintofile_tb1values(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>selectsid,serial#,username,decode(command,
20,none,
32,insert,
43,
5select,
66,update,
77,delete,
88,drop,
9other)cmdfromv$sessionwheretype!=background;

SIDSERIAL#USERNAMECMD
------------------------------------------------------
11none
21none
31none
41none
51none
61none
71275none
81275none
920GAOselect
1040GAOnone


53.DUMP(s,fmt,start,length)
DUMP函数以fmt指定的外部数字格局前往一个VARCHAR2范例的值
SQL>colglobal_namefora30
SQL>coldump_stringfora50
SQL>setlin200
SQL>selectglobal_name,dump(global_name,1017,8,5)dump_stringfromglobal_name;

GLOBAL_NAMEDUMP_STRING
--------------------------------------------------------------------------------
ORACLE.WORLDTyp=1Len=12CharacterSet=ZHS16GBK:W,O,R,L,D


54.EMPTY_BLOB()和EMPTY_CLOB()
这两个函数都是用来对年夜数据范例字段举行初始化操纵的函数


55.GREATEST
前往一组表达式中的最年夜值,即对照字符的编码巨细.
SQL>selectgreatest(AA,AB,AC)fromdual;

GR
--
AC
SQL>selectgreatest(啊,安,天)fromdual;

GR
--



56.LEAST
前往一组表达式中的最小值
SQL>selectleast(啊,安,天)fromdual;

LE
--



57.UID
前往标识以后用户的独一整数
SQL>showuser
USER为"GAO"
SQL>selectusername,user_idfromdba_userswhereuser_id=uid;

USERNAMEUSER_ID
---------------------------------------
GAO25



58.USER
前往以后用户的名字
SQL>selectuserfromdual;

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


59.USEREVN
前往以后用户情况的信息,opt能够是:
ENTRYID,SESSIONID,TERMINAL,ISDBA,LABLE,LANGUAGE,CLIENT_INFO,LANG,VSIZE
ISDBA检察以后用户是不是是DBA假如是则前往true
SQL>selectuserenv(isdba)fromdual;

USEREN
------
FALSE
SQL>selectuserenv(isdba)fromdual;

USEREN
------
TRUE
SESSION
前往会话标记
SQL>selectuserenv(sessionid)fromdual;

USERENV(SESSIONID)
--------------------
152
ENTRYID
前往会话生齿标记
SQL>selectuserenv(entryid)fromdual;

USERENV(ENTRYID)
------------------
0
INSTANCE
前往以后INSTANCE的标记
SQL>selectuserenv(instance)fromdual;

USERENV(INSTANCE)
-------------------
1
LANGUAGE
前往以后情况变量
SQL>selectuserenv(language)fromdual;

USERENV(LANGUAGE)
----------------------------------------------------
SIMPLIFIEDCHINESE_CHINA.ZHS16GBK
LANG
前往以后情况的言语的缩写
SQL>selectuserenv(lang)fromdual;

USERENV(LANG)
----------------------------------------------------
ZHS
TERMINAL
前往用户的终端或呆板的标记
SQL>selectuserenv(terminal)fromdual;

USERENV(TERMINA
----------------
GAO
VSIZE(X)
前往X的巨细(字节)数
SQL>selectvsize(user),userfromdual;

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



60.AVG(DISTINCT|ALL)
all暗示对一切的值求均匀值,distinct只对分歧的值求均匀值
SQLWKS>createtabletable3(xmvarchar(8),salnumber(7,2));
语句已处置。
SQLWKS>insertintotable3values(gao,1111.11);
SQLWKS>insertintotable3values(gao,1111.11);
SQLWKS>insertintotable3values(zhu,5555.55);
SQLWKS>commit;

SQL>selectavg(distinctsal)fromgao.table3;

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

SQL>selectavg(allsal)fromgao.table3;

AVG(ALLSAL)
-----------
2592.59


61.MAX(DISTINCT|ALL)
求最年夜值,ALL暗示对一切的值求最年夜值,DISTINCT暗示对分歧的值求最年夜值,不异的只取一次
SQL>selectmax(distinctsal)fromscott.emp;

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


62.MIN(DISTINCT|ALL)
求最小值,ALL暗示对一切的值求最小值,DISTINCT暗示对分歧的值求最小值,不异的只取一次
SQL>selectmin(allsal)fromgao.table3;

MIN(ALLSAL)
-----------
1111.11


63.STDDEV(distinct|all)
求尺度差,ALL暗示对一切的值求尺度差,DISTINCT暗示只对分歧的值求尺度差
SQL>selectstddev(sal)fromscott.emp;

STDDEV(SAL)
-----------
1182.5032

SQL>selectstddev(distinctsal)fromscott.emp;

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



64.VARIANCE(DISTINCT|ALL)
求协方差

SQL>selectvariance(sal)fromscott.emp;

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


65.GROUPBY
次要用来对一组数举行统计
SQL>selectdeptno,count(*),sum(sal)fromscott.empgroupbydeptno;

DEPTNOCOUNT(*)SUM(SAL)
---------------------------
1038750
20510875
3069400



66.HAVING
对分组统计再加限定前提
SQL>selectdeptno,count(*),sum(sal)fromscott.empgroupbydeptnohavingcount(*)>=5;

DEPTNOCOUNT(*)SUM(SAL)
---------------------------
20510875
3069400
SQL>selectdeptno,count(*),sum(sal)fromscott.emphavingcount(*)>=5groupbydeptno;

DEPTNOCOUNT(*)SUM(SAL)
---------------------------
20510875
3069400


67.ORDERBY
用于对查询到的了局举行排序输入
SQL>selectdeptno,ename,salfromscott.emporderbydeptno,saldesc;

DEPTNOENAMESAL
----------------------------
10KING5000
10CLARK2450
10MILLER1300
20SCOTT3000
20FORD3000
20JONES2975
20ADAMS1100
20SMITH800
30BLAKE2850
30ALLEN1600
30TURNER1500
30WARD1250
30MARTIN1250
30JAMES950


Oracle最经常使用功效函数典范汇总ChinaITLab搜集收拾2004-6-1410:58:00  *SQLGroupFunction
*
s(numcanbeacolumnorex

pression)          

  (nullvaluesareign
*
ored,defaultbetweendistin

ctandallisall)      

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

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

  AVG(num)   
--averagevalue
  COUNT(distinctorall]num)  
--numberofvalues
  MAX([distinctorall
]num)   --maximumvalue

  MAX(num)   
--minimumvalue
  STDDEV([distinctor
all]num) --standarddevi
ation
  SUM([distinctorall
]num)   --sumofvalues

  VARIANCE([distincto
rall]num)--varianceofv
alues
     ********************************
***********************
************************

  *MiscellaneaousFunctions:  
*
                       

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

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

  DECODE(expr,srch1,
return1[,srch2,return2...]
,default]
     --ifnosearchmatchest
heexpressionthenthedefaultisreturned,
     --otherwise,
thefirstsearchthatmatch
eswillcause
     --thecorres
pondingreturnvaluetober
eturned
  DUMP(column_name[,fmt[,start_p
os[,length]]])
     --returnsan
column
internaloracleformat,used

forgettinginfoabouta

     --formatoptions:8=oc
tal,10=decimel,16=hex,17=characters
     --returntype
codes:1=varchar2,2=n
umber,8=long,12=date,
     -- 23=raw,
24=longraw,69=rowid,
96=char,106=mlslabel
  GREATEST(expr[,expr2[,expr3...]]     --returnsthelargestval
ueofallexpressions
  LEAST(expr[,expr2[,expr3...]]     --returnsthe
smallestvalueofallexpre
ssions
  NVL(expr1,expr2     --ifexpr1isnotnull,i
tisreturned,otherwiseexpr2isreturned
  SQLCODE     --returnssqlerrorcode
query,
oflasterror. Cannotbeuseddirectlyin

     --valuemust
besettolocalvariablefir
st
  SQLERRM     --returnssql
inquery,
errormessageoflasterror

. Cannotbeuseddirectly

     --valuemustbesettolo
calvariablefirst
  UID     --returnstheuseridof
theuseryouareloggedonas
     --usefulins
electinginformationfromlo
wlevelsystables
  USER     --returnsthe
usernameoftheuseryoua
reloggedonas
  USERENV(option)     --returnsinf
ormationabouttheuseryou
areloggedonas
     --options:E
NTRYID,SESSIONID,TERMINAL,
LANGUAGE,LABEL,OSDBA
     --     (
alloptionsnotavailablein
allOracleversions)
  VSIZE(expr)     --returnsthenumberofb
ytesusedbytheexpression
     --usefulins
electinginformationaboutt
ablespacerequirements
     ********************
***************
****************************

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

  *SQLDateFunctions(dtreprese
*
ntsoracledateandtime)          

  *(functionsreturn
*
anoracledateunlessotherw

isespecified)        

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

  ADD_MONTHS(dt,num)
   --addsnummonthsto
dt(numcanbenegative)
  LAST_DAY(dt)    
  --lastdayofmonthin
monthcontainingdt
  MONTHS_BETWEEN(dt1,dt2)--retu
dt2
rnsfractionalvalueofmonthsbetweendt1,

  NEW_TIME(dt,tz1,tz
zone2
2) --dt=dateintimezo

ne1,returnsdateintime

  NEXT_DAY(dt,str)    --date
etc..)
offirst(str)afterdt(str=Monday,

  SYSDATE         --presentsystemdate  ROUND(dt[,fmt]     --roun
dsdtasspecifiedbyformatfmt
  TRUNC(dt[,fmt]  
   --truncatesdtasspe
cifiedbyformatfmt
     ********************************
***********************
************************

  *NumberFunctions:      
*
                       

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

  ABS(num)      --absolute
valueofnum
  CEIL(num)      --smallestinteger>or=num
  COS(num)      --cosine(n
um),numinradians
  COSH(num)     
 --hyperboliccosine(num)

  EXP(num)      
--eraisedtothenumpowe
r
  FLOOR(num)     --largest
integer<or=num
  LN(num)       --natural
logarithmofnum
  LOG(num2,num1)   --logarith
mbasenum2ofnum1
  MOD(num2,num1)   --remainde
rofnum2/num1
  POWER(num2,num1) 
 --num2raisedtothenum1
power
  ROUND(num1[,num2] --num1rou
ndedtonum2decimelplaces(default0)
  SIGN(num)      --signof
num*1,0ifnum=0
  SIN(num)      
--sin(num),numinradians

  SINH(num)      --hyperbolicsine(num)  SQRT(num)      --squarerootofnum  TAN(num)      --tangent(
num),numinradians
  TANH(num)     
 --hyperbolictangent(num)

  TRUNC(num1[,num2] --truncate
num1tonum2decimelplaces(default0)
     ********************************
***********************
************************

  *StringFunctions,
*
StringResult:      

               

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

  (num)         --ASCII
characterfornum
  CHR(num)      
  --ASCIIcharacterforn
um
  CONCAT(str1,str2)   --str1
concatenatedwithstr2(sameasstr1||str2)
  INITCAP(str)    
  --capitalizefirstlett
erofeachwordinstr
  LOWER(str)       --strw
ithalllettersinlowercase
  LPAD(str1,num[,str2])--left
spaces)
padstr1tolengthnumwithstr2(default

  LTRIM(str[,set]) 
  --removesetfromleft
sideofstr(defaultspaces)
  NLS_INITCAP(str[,nl
s_val])--sameasinitcapf
ordifferentlanguages
  NLS_LOWER(str[,nls_
val]) --sameaslowerfor
differentlanguages
  REPLACE(str1,str2[,str3])--r
eplacesstr2withstr3instr1
                --
deletesstr2fromstr1ifstr3isomitted
  RPAD(str1,num[,str
(defaultspaces)
2])  --rightpadstr1to

lengthnumwithstr2

  RTRIM(str[,set]) 
spaces)
    --removesetfrom

rightsideofstr(default

  SOUNDEX(str)    
    --phoneticrepresen
tationofstr
  SUBSTR(str,num2[,n
um1]) --substringofstr,
startingwithnum2,
                --
omitted)
num1characters(toendofstrifnum1is

  SUBSTRB(str,num2[,
bytes
num1]) --sameassubstrbu

tnum1,num2expressedin

  TRANSLATE(str,set1,
set2) --replacesset1in
strwithset2
                --
truncated
ifset2islongerthanset1,itwillbe

  UPPER(str)     
    --strwithalllett
ersinuppercase
     ********************
***************
****************************

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

  *StringFunctions,
*
NumericResult:      

               

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

     ASCII(str)           
 --ASCIIvalueofstr
  INSTR(str1,str2[,num1[,num2]]
)--positionofnum2thoccurrenceof
                  
 --str2instr1,startingatnum1
                  
 --(num1,num2defaultto1)
  INSTRB(str1,str2[,num1]

)--sameasinstr,bytevaluesfornum1,num2

  LENGTH(str)    
       --numberof
charactersinstr
  LENGTHB(str)          
 --numberofbytesinstr
  NLSSORT(str[,nls_val])    
 --nls_valbytevalueofstr
     ********************************
***********************
************************

  *SQLConversionFunctions   
*
                       

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

  CHARTOROWID(str)        
 --convertsstrtoROWID
  CONVERT(str,chr_set2[,chr_set1
])--convertsstrtochr_set2
            
characterset
        --chr_set1

defaultisthedatbase

  HEXTORAW(str)   
 --convertshexstringva
luetointernalrawvalues
  RAWTOHEX(raw_val)  --convert
srawhexvaluetohexstringvalue
  ROWIDTOCHAR(rowid) 
 --convertsrowidto18ch
aracterstringformat
  TO_CHAR(expr[,fmt])
fmt
 --convertsexpr(dateorn

umber)toformatspecifiedby

  TO_DATE(str[,fmt])
 --convertsstringtodat
e
  TO_MULTI_BYTE(str)  --convert
ssinglebytestringtomultibytestring
  TO_NUMBER(str[,fmt])--convert
sstrtoanumberformattedbyfmt
  TO_SINGLE_BYTE(str)
 --convertsmultibytest
ringtosinglebytestring
     ********************************
***********************
************************

  *SQLDateFormats 
*
              

               

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

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

     BC,B.C.    BCindicator  AD,A.D.    ADindicator  CC,SCC    Cent
uryCode(SCCincludesspace
or-sign)
  YYYY,SYYYY  4digityear(SY
YYYincludesspaceor-sign)
  IYYY      4digitISOyear  Y,YYY     4digityearwithcomma  YYY,YY,orY last3,2,or1
digitofyear
  YEAR,SYEAR  yearspelledout
(SYEARincludesspaceor-sign)
  RR       last2digitsof
yearinpriorornextcentury
  Q       quarteroryear,1to4  MM       month-from01to12  MONTH     monthspelledout  MON      month3letterabbreviation  RM       romannumeralformonth  WW       weekofyear,1to53  IW       ISOweekofyear
,1to52or1to53
  W       weekofmonth,1
to5(week1begins1stdayofthemonth)
  D       dayofweek,1to7  DD       dayofmonth,1to31  DDD      dayofyear,1to366  DAY      dayofweekspel
ledout,ninecharactersrightpadded
  DY       dayabbreviation  J       #of
dayssinceJan1,4712BC

  HH,HH12    hourofday,1to12  HH24      hourofday,0to23  MI       minuteofhour,0to59  SS       secondofminute,0to59  SSSSS     seco
ndspastmidnight,0to8639
9
  AM,A.M.    amindicator  PM,P.M.    pmindicator  anypuctuation punc
tuationbetweenformatitems
,asinDD/MM/YY
  anytext    textbetweenformatitems  TH       conv
erts1to1st,2to2nd,
andsoon
  SP       converts1too
ne,2totwo,andsoon
  SPTH      converts1toF
IRST,2toSECOND,andsoon
  FX       fill
exact:usesexactpattern
matching
  FM       fillmode :tog
glessuppressionofblanksinoutput

MySQL已经为支持所有最流行的Web2.0语言做好了准备,诸如Ruby、Ajax等,当然还有PHP。有的业界分析师说过,“每一个Web2.0公司实质上就是一个数据库公司。

蒙在股里 发表于 2015-1-19 21:13:52

大家注意一点。如下面的例子:

深爱那片海 发表于 2015-1-28 10:59:15

外键的级联更能扩展可能大部分的同行在设计OLTP系统的时候都不愿意建立外键,都是通过程序来控制父子数据的完整性。

变相怪杰 发表于 2015-2-5 20:58:26

对于微软系列的东西除了一遍遍尝试还真没有太好的办法

兰色精灵 发表于 2015-2-13 14:42:16

记得在最开始使用2k的时候就要用到这个功能,可惜2k没有,现在有了作解决方案的朋友会很高兴吧。

飘灵儿 发表于 2015-3-3 22:52:43

可以动态传入参数,省却了动态SQL的拼写。

仓酷云 发表于 2015-3-11 14:29:14

呵呵,这就是偶想说的

再现理想 发表于 2015-3-18 23:35:15

财务软件要用SQL也只是后台的数据库而已,软件都是成品的,当然多学东西肯定是有好处的..

再见西城 发表于 2015-3-26 20:47:48

是要和操作系统进行Socket通讯的场景。否则建议慎重!
页: [1]
查看完整版本: MYSQL网页设计ORACLE函数年夜全