TO_CHAR IN ORACLE - Online Tech Support

This tutorial page is based on examples to be easier to follow. The Oracle TO_CHAR function allows converting others’ data types value to character type and function To_Char always returns VARCHAR2 type. You can convert to VARCHAR2 for example DATE, NUMBER, NCHAR, NVARCHAR2, CLOB, or NCLOB data types. The TO_CHAR syntax is following:

TO_CHAR(<datatype>[,<data_mask>])

Take a look at the examples below to see how works Oracle TO_CHAR. For example the first query is number “01234” without To_Char function and the nature of this type is getting trimmed by Oracle database so the SQL output returns “1234“.

SELECT 01234 
  FROM DUAL;

The reason why Oracle database removed the first 0 (zero) is to keep the database tidy and that way the number looks less confusing for users. Having a zero in front of 1234 doesn’t make much sense either so it gets cleaned away.

Now to keep the number as with the original look, you should use Oracle To_Char function and store the value into Oracle database table as VARCHAR2 type because numbers like phone numbers or credit card numbers starting with 0 (zero) wouldn’t be valid after removing the first zero. We can’t treat all numbers as “numbers” since there are numbers that should keep their look to remain correct and valid.

The second example demonstrates how will stay a number treated as text and to keep its look. This is a demonstrational query so we wrote the number as text and To_Char function is not needed in this case but you can use this example with other datatype variables in place of ‘01234‘. Take a look at the following query and note that Oracle database left the first zero as is and your phone numbers wouldn’t be ruined using this VARCHAR2 type.

SELECT TO_CHAR('01234') 
  FROM DUAL;

Also Oracle To_Char can be used to give numbers a certain look so they look better and more clear on a report or a bill. To format a number you would need to use a data mask and for numbers there are limited amount of key-letters. To see number formatting element take a look at the table below or this link will send you directly to Oracle webpage for possible mask elements. The mask key-letters should be used only with Oracle To_Char as on the following example. On this example we are filling in missing zeros after the coma point to have always two places after the decimal point.

SELECT TO_CHAR(111.2,'990D00') AS formatted_number
  FROM DUAL;

Changing value from number to character is not as popular as turning it from a date type to text and the following part of this tutorial will continue with date values. To change a date look you would need to use a mask again but this time with different mask elements. For example the following Oracle To_Char example has a mask as year(YYYY)-month(MM)-day(DD) hours in 24 digits(HH24):minutes(MI):seconds(SS).

SELECT TO_CHAR(SYSDATE,'YYYY-MM-DD HH24:MI:SS') AS date_to_char
  FROM DUAL;

Also here you can find a list of possible Oracle masks elements for a date type. Use those mask elements only with To_Char function.

Number Format Elements	Example	Description
, (comma)	`9,999`	Returns a comma in the specified position. You can specify multiple commas in a number format model.Restrictions: A comma element cannot begin a number format model. A comma cannot appear to the right of a decimal character or period in a number format model.
. (period)	`99.99`	Returns a decimal point, which is a period (.) in the specified position.Restriction: You can specify only one period in a number format model.
$	`$9999`	Returns value with a leading dollar sign.
0	`09999990`	Returns leading zeros.Returns trailing zeros.
9	`9999`	Returns value with the specified number of digits with a leading space if positive or with a leading minus if negative. Leading zeros are blank, except for a zero value, which returns a zero for the integer part of the fixed-point number.
B	`B9999`	Returns blanks for the integer part of a fixed-point number when the integer part is zero (regardless of zeros in the format model).
C	`C999`	Returns in the specified position the ISO currency symbol (the current value of the `NLS_ISO_CURRENCY` parameter).
D	`99D99`	Returns in the specified position the decimal character, which is the current value of the `NLS_NUMERIC_CHARACTER` parameter. The default is a period (.).Restriction: You can specify only one decimal character in a number format model.
EEEE	`9.9EEEE`	Returns a value using in scientific notation.
G	`9G999`	Returns in the specified position the group separator (the current value of the `NLS_NUMERIC_CHARACTER` parameter). You can specify multiple group separators in a number format model.Restriction: A group separator cannot appear to the right of a decimal character or period in a number format model.
L	`L999`	Returns in the specified position the local currency symbol (the current value of the `NLS_CURRENCY` parameter).
MI	`9999MI`	Returns negative value with a trailing minus sign (-).Returns positive value with a trailing blank.Restriction: The MI format element can appear only in the last position of a number format model.
PR	`9999PR`	Returns negative value in <angle brackets>.Returns positive value with a leading and trailing blank.Restriction: The PR format element can appear only in the last position of a number format model.
RNrn	`RNrn`	Returns a value as Roman numerals in uppercase.Returns a value as Roman numerals in lowercase.Value can be an integer between 1 and 3999.
S	`S99999999S`	Returns negative value with a leading minus sign (-).Returns positive value with a leading plus sign (+).Returns negative value with a trailing minus sign (-).Returns positive value with a trailing plus sign (+).Restriction: The S format element can appear only in the first or last position of a number format model.
TM	`TM`	The text minimum number format model returns (in decimal output) the smallest number of characters possible. This element is case insensitive.The default is TM9, which returns the number in fixed notation unless the output exceeds 64 characters. If the output exceeds 64 characters, then Oracle Database automatically returns the number in scientific notation.Restrictions: You cannot precede this element with any other element. You can follow this element only with one 9 or one E (or e), but not with any combination of these. The following statement returns an error:`SELECT TO_CHAR(1234, 'TM9e') FROM DUAL;`
U	`U9999`	Returns in the specified position the Euro (or other) dual currency symbol, determined by the current value of the `NLS_DUAL_CURRENCY` parameter.
V	`999V99`	Returns a value multiplied by 10ⁿ (and if necessary, round it up), where `n` is the number of 9’s after the `V`.
X	`XXXXxxxx`	Returns the hexadecimal value of the specified number of digits. If the specified number is not an integer, then Oracle Database rounds it to an integer.Restrictions: This element accepts only positive values or 0. Negative values return an error. You can precede this element only with 0 (which returns leading zeroes) or FM. Any other elements return an error. If you specify neither 0 nor FM with X, then the return always has one leading blank.

Datetime Format Element	TO_* Datetime functions?	Description
- / , . ; : "text"	Yes	Punctuation and quoted text is reproduced in the result.
AD A.D.	Yes	AD indicator with or without periods.
AM A.M.	Yes	Meridian indicator with or without periods.
BC B.C.	Yes	BC indicator with or without periods.
CC SCC		Century. If the last 2 digits of a 4-digit year are between 01 and 99 (inclusive), then the century is one greater than the first 2 digits of that year. If the last 2 digits of a 4-digit year are 00, then the century is the same as the first 2 digits of that year. For example, 2002 returns 21; 2000 returns 20.
D	Yes	Day of week (1-7). This element depends on the NLS territory of the session.
DAY	Yes	Name of day.
DD	Yes	Day of month (1-31).
DDD	Yes	Day of year (1-366).
DL	Yes	Returns a value in the long date format, which is an extension of the Oracle Database `DATE` format, determined by the current value of the `NLS_DATE_FORMAT` parameter. Makes the appearance of the date components (day name, month number, and so forth) depend on the `NLS_TERRITORY` and `NLS_LANGUAGE` parameters. For example, in the `AMERICAN_AMERICA` locale, this is equivalent to specifying the format `'fmDay,` `Month` `dd,` `yyyy'`. In the `GERMAN_GERMANY` locale, it is equivalent to specifying the format ‘`fmDay, dd.` `Month yyyy`‘.Restriction: You can specify this format only with the `TS` element, separated by white space.
DS	Yes	Returns a value in the short date format. Makes the appearance of the date components (day name, month number, and so forth) depend on the `NLS_TERRITORY` and `NLS_LANGUAGE` parameters. For example, in the `AMERICAN_AMERICA` locale, this is equivalent to specifying the format ‘`MM/DD/RRRR`‘. In the `ENGLISH_UNITED_KINGDOM` locale, it is equivalent to specifying the format ‘`DD/MM/RRRR`‘.Restriction: You can specify this format only with the `TS` element, separated by white space.
DY	Yes	Abbreviated name of day.
E	Yes	Abbreviated era name (Japanese Imperial, ROC Official, and Thai Buddha calendars).
EE	Yes	Full era name (Japanese Imperial, ROC Official, and Thai Buddha calendars).
FF [1..9]	Yes	Fractional seconds; no radix character is printed. Use the X format element to add the radix character. Use the numbers 1 to 9 after FF to specify the number of digits in the fractional second portion of the datetime value returned. If you do not specify a digit, then Oracle Database uses the precision specified for the datetime data type or the data type’s default precision. Valid in timestamp and interval formats, but not in `DATE` formats.Examples: `'HH:MI:SS.FF'SELECT TO_CHAR(SYSTIMESTAMP, 'SS.FF3') from DUAL;`
FM	Yes	Returns a value with no leading or trailing blanks.See Also: Additional discussion on this format model modifier in the Oracle Database SQL Language Reference
FX	Yes	Requires exact matching between the character data and the format model.See Also: Additional discussion on this format model modifier in the Oracle Database SQL Language Reference
HH HH12	Yes	Hour of day (1-12).
HH24	Yes	Hour of day (0-23).
IW		Week of year (1-52 or 1-53) based on the ISO standard.
IYY IY I		Last 3, 2, or 1 digit(s) of ISO year.
IYYY		4-digit year based on the ISO standard.
J	Yes	Julian day; the number of days since January 1, 4712 BC. Number specified with J must be integers.
MI	Yes	Minute (0-59).
MM	Yes	Month (01-12; January = 01).
MON	Yes	Abbreviated name of month.
MONTH	Yes	Name of month.
PM P.M.	Yes	Meridian indicator with or without periods.
Q		Quarter of year (1, 2, 3, 4; January – March = 1).
RM	Yes	Roman numeral month (I-XII; January = I).
RR	Yes	Lets you store 20th century dates in the 21st century using only two digits.See Also: “The RR Datetime Format Element”
RRRR	Yes	Round year. Accepts either 4-digit or 2-digit input. If 2-digit, provides the same return as RR. If you do not want this functionality, then enter the 4-digit year.
SS	Yes	Second (0-59).
SSSSS	Yes	Seconds past midnight (0-86399).
TS	Yes	Returns a value in the short time format. Makes the appearance of the time components (hour, minutes, and so forth) depend on the `NLS_TERRITORY` and `NLS_LANGUAGE` initialization parameters.Restriction: You can specify this format only with the `DL` or `DS` element, separated by white space.
TZD	Yes	Daylight saving information. The TZD value is an abbreviated time zone string with daylight saving information. It must correspond with the region specified in TZR. Valid in timestamp and interval formats, but not in `DATE` formats.Example: `PST` (for US/Pacific standard time); `PDT` (for US/Pacific daylight time).
TZH	Yes	Time zone hour. (See `TZM` format element.) Valid in timestamp and interval formats, but not in `DATE` formats.Example: `'HH:MI:SS.FFTZH:TZM'`.
TZM	Yes	Time zone minute. (See `TZH` format element.) Valid in timestamp and interval formats, but not in `DATE` formats.Example: `'HH:MI:SS.FFTZH:TZM'`.
TZR	Yes	Time zone region information. The value must be one of the time zone region names supported in the database. Valid in timestamp and interval formats, but not in `DATE` formats.Example: US/Pacific
WW		Week of year (1-53) where week 1 starts on the first day of the year and continues to the seventh day of the year.
W		Week of month (1-5) where week 1 starts on the first day of the month and ends on the seventh.
X	Yes	Local radix character.Example: `'HH:MI:SSXFF'`.
Y,YYY	Yes	Year with comma in this position.
YEAR SYEAR		Year, spelled out; `S` prefixes BC dates with a minus sign (-).
YYYY SYYYY	Yes	4-digit year; `S` prefixes BC dates with a minus sign.
YYY YY Y	Yes	Last 3, 2, or 1 digit(s) of year.