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* SQL Group Functions (num can be a column or expression) *
(null values are ignored, default between distinct 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 deviation
SUM([distinct or all] num) – sum of values
VARIANCE([distinct or all] num) — variance of values
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* Miscellaneaous Functions : *
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DECODE(expr, srch1, return1 [,srch2, return2...], default]
– if no search matches the expression then the default is returned,
– otherwise, the first search that matches will cause
– the corresponding return value to be returned
DUMP(column_name [,fmt [,start_pos [, length]]])
– returns an internal oracle format, used for getting info about a column
– format options : 8 = octal, 10 = decimel, 16 = hex, 17 = characters
– return type codes : 1 = varchar2, 2 = number, 8 = long, 12 = date,
– 23 = raw, 24 = long raw, 69 = rowid, 96 = char, 106 = mlslabel
GREATEST(expr [,expr2 [, expr3...]]
– returns the largest value of all expressions
LEAST(expr [,expr2 [, expr3...]]
– returns the smallest value of all expressions
NVL(expr1 ,expr2
– if expr1 is not null, it is returned, otherwise expr2 is returned
SQLCODE
– returns sql error code of last error. Can not be used directly in query,
– value must be set to local variable first
SQLERRM
– returns sql error message of last error. Can not be used directly in query,
– value must be set to local variable first
UID
– returns the user id of the user you are logged on as
– useful in selecting information from low level sys tables
USER
– returns the user name of the user you are logged on as
USERENV(‘option’)
– returns information about the user you are logged on as
– options : ENTRYID, SESSIONID, TERMINAL, LANGUAGE, LABEL, OSDBA
– (all options not available in all Oracle versions)
VSIZE(expr)
– returns the number of bytes used by the expression
– useful in selecting information about table space requirements
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* SQL Date Functions (dt represents oracle date and time) *
* (functions return an oracle date unless otherwise 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) — returns fractional value of months between dt1, dt2
NEW_TIME(dt, tz1, tz2) – dt = date in time zone 1, returns date in time zone 2
NEXT_DAY(dt, str) – date of first (str) after dt (str = ‘Monday’, etc..)
SYSDATE – present system date
ROUND(dt [,fmt] — rounds dt as specified by format fmt
TRUNC(dt [,fmt] — truncates dt as specified by format fmt
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* Number Functions : *
*******************************************************************************
ABS(num) — absolute value of num
CEIL(num) – smallest integer > or = num
COS(num) — cosine(num), num in radians
COSH(num) – hyperbolic cosine(num)
EXP(num) — e raised to the num power
FLOOR(num) – largest integer < or = num
LN(num) – natural logarithm of num
LOG(num2, num1) – logarithm base num2 of num1
MOD(num2, num1) – remainder of num2 / num1
POWER(num2, num1) — num2 raised to the num1 power
ROUND(num1 [,num2] – num1 rounded 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 : *
*******************************************************************************
(num) — ASCII character for num
CHR(num) — ASCII character for num
CONCAT(str1, str2) – str1 concatenated with str2 (same as str1||str2)
INITCAP(str) – capitalize first letter of each word in str
LOWER(str) – str with all letters in lowercase
LPAD(str1, num [,str2]) — left pad str1 to length num with str2 (default spaces)
LTRIM(str [,set]) — remove set from left side of str (default spaces)
NLS_INITCAP(str [,nls_val]) — same as initcap for different languages
NLS_LOWER(str [,nls_val]) – same as lower for different languages
REPLACE(str1, str2 [,str3]) — replaces str2 with str3 in str1
– deletes str2 from str1 if str3 is omitted
RPAD(str1, num [,str2]) – right pad str1 to length num with str2 (default spaces)
RTRIM(str [,set]) – remove set from right side of str (default spaces)
SOUNDEX(str) — phonetic representation of str
SUBSTR(str, num2 [,num1]) – substring of str, starting with num2,
– num1 characters (to end of str if num1 is omitted)
SUBSTRB(str, num2 [,num1]) – same as substr but num1, num2 expressed in bytes
TRANSLATE(str, set1, set2) – replaces set1 in str with set2
– if set2 is longer than set1, it will be truncated
UPPER(str) – str with all letters in uppercase
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* 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
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* SQL Conversion Functions *
*******************************************************************************
CHARTOROWID(str) — converts str to ROWID
CONVERT(str, chr_set2 [,chr_set1]) — converts str to chr_set2
– chr_set1 default is the datbase character set
HEXTORAW(str) – converts hex string value to internal raw values
RAWTOHEX(raw_val) – converts raw hex value to hex string value
ROWIDTOCHAR(rowid) — converts rowid to 18 character string format
TO_CHAR(expr [,fmt]) – converts expr(date or number) to format specified by fmt
TO_DATE(str [,fmt]) – converts string to date
TO_MULTI_BYTE(str) — converts single byte string to multi byte string
TO_NUMBER(str [,fmt]) — converts str to a number formatted by fmt
TO_SINGLE_BYTE(str) – converts multi byte string to single byte string
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* SQL Date Formats *
*******************************************************************************
BC, B.C. BC indicator
AD, A.D. AD indicator
CC, SCC Century Code (SCC includes space or – sign)
YYYY, SYYYY 4 digit year (SYYYY 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 spelled 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 seconds past midnight, 0 to 86399
AM, A.M. am indicator
PM, P.M. pm indicator
any puctuation punctuation between format items, as in ‘DD/MM/YY’
any text text between format items
TH converts 1 to ’1st’, 2 to ’2nd’, and so on
SP converts 1 to ‘one’, 2 to ‘two’, and so on
SPTH converts 1 to ‘FIRST’, 2 to ‘SECOND’, and so on
FX fill exact : uses exact pattern matching
FM fill mode : toggles suppression of blanks in output
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