Oracle date format

With the functions to_char and to_date, a date format can be used.

Example:
select to_char(sysdate,'DD/MM/YYYY HH24:MI:SS') from dual;
will return something like: 24/03/2006 14:36:43

Here is a list of all the formats that can be used:
Format mask Description
CC Century
SCC Century BC prefixed with -
YYYY Year with 4 numbers
SYYY Year BC prefixed with -
IYYY ISO Year with 4 numbers
YY Year with 2 numbers
RR Year with 2 numbers with Y2k compatibility
YEAR Year in characters
SYEAR Year in characters, BC prefixed with -
BC BC/AD Indicator *
Q Quarter in numbers (1,2,3,4)
MM Month of year 01, 02...12
MONTH Month in characters (i.e. January)
MON JAN, FEB
WW Weeknumber (i.e. 1)
W Weeknumber of the month (i.e. 5)
IW Weeknumber of the year in ISO standard.
DDD Day of year in numbers (i.e. 365)
DD Day of the month in numbers (i.e. 28)
D Day of week in numbers(i.e. 7)
DAY Day of the week in characters (i.e. Monday)
FMDAY Day of the week in characters (i.e. Monday)
DY Day of the week in short character description (i.e. SUN)
J Julian Day (number of days since January 1 4713 BC, where January 1 4713 BC is 1 in Oracle)
HH Hournumber of the day (1-12)
HH12 Hournumber of the day (1-12)
HH24 Hournumber of the day with 24Hours notation (1-24)
AM AM or PM
PM AM or PM
MI Number of minutes (i.e. 59)
SS Number of seconds (i.e. 59)
SSSSS Number of seconds this day.
DS Short date format. Depends on NLS-settings. Use only with timestamp.
DL Long date format. Depends on NLS-settings. Use only with timestamp.
E Abbreviated era name. Valid only for calendars: Japanese Imperial, ROC Official and Thai Buddha.. (Input-only)
EE The full era name
FF The fractional seconds. Use with timestamp.
FF1..FF9 The fractional seconds. Use with timestamp. The digit controls the number of decimal digits used for fractional seconds.
FM Fill Mode: suppresses blianks in output from conversion
FX Format Exact: requires exact pattern matching between data and format model.
IYY or IY or I the last 3,2,1 digits of the ISO standard year. Output only
RM The Roman numeral representation of the month (I .. XII)
RR The last 2 digits of the year.
RRRR The last 2 digits of the year when used for output. Accepts fout-digit years when used for input.
SCC Century. BC dates are prefixed with a minus.
CC Century
SP Spelled format. Can appear of the end of a number element. The result is always in english. For example month 10 in format MMSP returns "ten"
SPTH Spelled and ordinal format; 1 results in first.
TH Converts a number to it's ordinal format. For example 1 becoms 1st.
TS Short time format. Depends on NLS-settings. Use only with timestamp.
TZD Abbreviated time zone name. ie PST.
TZH Time zone hour displacement.
TZM Time zone minute displacement.
TZR Time zone region
X Local radix character. In america this is a period (.)

SUBSTR

SUBSTR Returns a substring. For more information see Oracle substring
SUBSTRB Returns a substring expressed in bytes instead of characters.
SUBSTRC Returns a substring expressed in Unicode code points instead of characters.
SUBSTR2 Returns a substring using USC2 code points.
SUBSTR4 Returns a substring using USC4 code points.

SOUNDEX

SOUNDEX returns a character string containing the phonetic representation of char. This function lets you compare words that are spelled differently, but sound alike in English.

Example: select * from emp where lastname SOUNDEX('SMITH');

RTRIM

RTRIM removed characters from the right of a string if they are equal to the specified string.

Example: rtrim('bcaaaaaa','a') = 'bc'

If the last parameter is not specified, spaces are removed from the right side.

RPAD

Add characters to the right of a string until a fixed number is reached.

Example: rpad('abc',8,'x') = 'abcxxxxx'.

If the last parameter is not specified, spaces are added to the right.

REVERSE

Reverses the characters of a String.

Example: REVERSE('1234567890') = '0987654321'

REPLACE

The replace function replaces every occurrence of a search_string with a new string. If no new string is specified, all occurrences of the search_string are removed.

Example: replace('a1a1a1','a','2') = '212121'.

LTRIM

LTRIM removed characters from the left of a string if they are equal to the specified string.

Example: ltrim('aaaaaabc','a') = 'bc'

If the last parameter is not specified, spaces are removed from the left side.