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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)

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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

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* Miscellaneaous Functions :

*

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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

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* SQL Date Functions (dt represe

*

nts oracle date and time)

* (functions return

*

an oracle date unless otherw

ise specified)

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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

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* Number Functions :

*

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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)

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* String Functions,

*

String Result :

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(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

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* String Functions,

*

Numeric Result :

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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

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* SQL Conversion Functions

*

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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

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* SQL Date Formats

*

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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