3 Row Functions

The OLAP row functions extend the syntax of the SQL row functions for use with dimensional objects. If you use the SQL row functions, then this syntax is familiar. You can use these functions on relational data when loading it into cubes and cube dimensions, and with the OLAP functions when creating calculated measures.

This chapter describes the row functions of the OLAP expression syntax. It contains these topics:

3.2 Row Functions By Category

The row functions are grouped into the following categories:

3.2.1 Numeric Functions

These functions accept numeric input and return numeric values:

3.2.2 Character Functions That Return Characters

These functions accept character input and return character values:

3.2.3 NLS Character Functions

These functions return information about a character set:

3.2.4 Character Functions That Return Numbers

These functions accept character input and return numeric values:

3.2.6 General Comparison Functions

These functions determine the greatest or least value in a set of values:

3.2.8 Encoding and Decoding Function

These functions return a numeric value for each input value:

3.2.9 Null-Related Functions

These functions facilitate null handling:

3.2.10 Environment and Identifier Functions

These functions provide information about the instance and the session:

3.3 ABS

ABS returns the absolute value of a numeric expression.

Return Value

NUMBER

Syntax

ABS(n)

Arguments

n is any numeric expression.

Example

ABS(-15) returns the value 15.

3.4 ACOS

ACOS calculates the angle value in radians of a specified cosine.

Return Value

NUMBER

Syntax

ACOS(n) 

Arguments

n is a numeric expression for the cosine in the range of -1 to 1.

Example

ACOS(.3) returns the value 1.26610367.

3.5 ADD_MONTHS

ADD_MONTHS returns a date that is a specified number of months after a specified date.

When the starting date is the last day of the month or when the returned month has fewer days, then ADD_MONTHS returns the last day of the month. Otherwise, the returned day is the starting day.

Return Value

DATE

Syntax

ADD_MONTHS(date, integer) 

Arguments

date is the starting date.

integer is the number of months to be added to the starting date.

Example

ADD_MONTHS('17-JUN-06', 1) returns the value 17-JUL-06.

3.6 ASCII

ASCII returns the decimal representation of the first character of an expression.

Return Value

NUMBER

Syntax

ASCII(char) 

Arguments

char can be any text expression.

Example

ASCII('Boston') returns the value 66, which is the ASCII equivalent of the letter B.

3.7 ASCIISTR

ASCIISTR converts a string in any character set to ASCII in the database character set. Non-ASCII characters are represented as \xxxx, where xxxx is a UTF-16 code unit.

Return Value

VARCHAR2

Syntax

ASCIISTR(char)

Arguments

char can be any character string.

Example

ASCIISTR('Skåne') returns the value Sk\00E5ne.

3.8 ASIN

ASIN calculates the angle value in radians of a specified sine.

Return Value

NUMBER

Syntax

ASIN(n) 

Arguments

n is a numeric expression in the range of -1 to 1 that contains the decimal value of a sine.

Example

ASIN(.3) returns the value 0.304692654.

3.9 ATAN

ATAN calculates the angle value in radians of a specified tangent.

Use ATAN2 to retrieve a full-range (0 - 2 pi) numeric value indicating the arc tangent of a given ratio.

Return Value

NUMBER

Syntax

ATAN(n) 

Arguments

n is a numeric expression that contains the decimal value of a tangent.

Example

ATAN(.3) returns the value 0.291456794.

3.10 ATAN2

ATAN2 returns a full-range (0 - 2 pi) numeric value of the arc tangent of a given ratio. The function returns values in the range of -pi to pi, depending on the signs of the arguments.

Use ATAN to calculate the angle value (in radians) of a specified tangent that is not a ratio.

Return Value

NUMBER

Syntax

ATAN2(n1, n2) 

Arguments

n1 and n2 are numeric expressions for the components of the ratio.

Example

ATAN2(.3, .2) returns the value 0.982793723.

3.11 BIN_TO_NUM

BIN_TO_NUM converts a bit vector to its equivalent number.

Return Value

NUMBER

Syntax

BIN_TO_NUM(expr [, expr ]... ) 

Arguments

expr is a numeric expression with a value of 0 or 1 for the value of a bit in the bit vector.

Example

BIN_TO_NUM(1,0,1,0) returns the value 10.

3.12 BITAND

BITAND computes an AND operation on the bits of two nonnegative integers, and returns an integer. This function is commonly used with the DECODE function.

An AND operation compares two bit values. If both values are 1, the operator returns 1. If one or both values are 0, the operator returns 0.

Return Value

NUMBER

Syntax

BITAND(expr1, expr2) 

Arguments

expr1 and expr2 are numeric expressions for nonnegative integers.

Example

BITAND(7, 29) returns the value 5.

The binary value of 7 is 111 and of 29 is 11101. A bit-by-bit comparison generates the binary value 101, which is decimal 5.

3.13 CAST

CAST converts values from one data type to another.

Return Value

The data type specified by type_name.

Syntax

CAST(expr AS type_name)

Arguments

expr can be an expression in one of the data types.

type_name is one of the data types listed in Table 1-2.

Table 3-1 shows which data types can be cast into which other built-in data types. NUMBER includes NUMBER, DECIMAL, and INTEGER. DATETIME includes DATE, TIMESTAMP, TIMESTAMP WITH TIMEZONE, and TIMESTAMP WITH LOCAL TIMEZONE. INTERVAL includes INTERVAL DAY TO SECOND and INTERVAL YEAR TO MONTH.

Table 3-1 Compatible Data Types

From To BINARY_FLOAT, BINARY_DOUBLE To CHAR, VARCHAR2 To NUMBER To DATETIME, INTERVAL To NCHAR, NVARCHAR2

BINARY_FLOAT, BINARY_DOUBLE

yes

yes

yes

no

yes

CHAR, VARCHAR2

yes

yes

yes

yes

no

NUMBER

yes

yes

yes

no

yes

DATETIME, INTERVAL

no

yes

no

yes

yes

NCHAR, NVARCHAR2

yes

no

yes

no

yes

Example

CAST('123.4567' AS NUMBER(10,2)) returns the value 123.46.

3.14 CEIL

CEIL returns the smallest whole number greater than or equal to a specified number.

Return Value

NUMBER

Syntax

CEIL(n) 

Arguments

n is a numeric expression.

Examples

CEIL(3.1415927) returns the value 4.

CEIL(-3.4) returns the value -3.00.

3.15 CHARTOROWID

CHARTOROWID converts a value from a text data type to a ROWID data type.

For more information about the ROWID pseudocolumn, refer to the Oracle Database SQL Language Reference.

Return Value

ROWID

Syntax

CHARTOROWID(char)

Arguments

char is a text expression that forms a valid rowid.

Example

chartorowid('AAAN6EAALAAAAAMAAB') returns the text string AAAN6EAALAAAAAMAAB as a rowid.

3.16 CHR

CHR converts an integer to the character with its binary equivalent in either the database character set or the national character set.

For single-byte character sets, if n > 256, then CHR converts the binary equivalent of mod(n, 256).

For the Unicode national character sets and all multibyte character sets, n must resolve to one entire code point. Code points are not validated, and the result of specifying invalid code points is indeterminate.

Return Value

VARCHAR2 | NVARCHAR2

Syntax

CHR(n [ USING NCHAR_CS ]) 

Arguments

n is a numeric expression.

USING NCHAR_CS returns a character in the national character set. Otherwise, the return value is in the database character set. The OLAP engine uses the UTF8 national character set, so the return value may be different from the SQL CHR function, which uses the database UTF16 national character set.

Example

CHR(67), CHR(67 USING NCHAR_CS), and CHR(323) all return the letter C on an ASCII-based system with the WE8DEC database character set and the UTF8 national character set. CHR(323) is evaluated as CHR(MOD(323, 256)).

3.17 COALESCE

COALESCE returns the first non-null expression in a list of expressions, or NULL when all of the expressions evaluate to null.

Return Value

Data type of the first argument

Syntax

COALESCE(expr [, expr ]...) 

Arguments

expr can be any expression.

Examples

COALESCE(5, 8, 3) returns the value 5.

COALESCE(NULL, 8, 3) returns the value 8.

3.18 CONCAT

CONCAT joins two expressions as a single character string. The data type of the return value is the same as the expressions, or if they are mixed, the one that results in a lossless conversion.

Return Value

CHAR | NCHAR | VARCHAR2 | NVARCHAR2

Syntax

CONCAT(char1, char2)

Arguments

char1 and char2 are text expressions.

Example

CONCAT('The current date is ', 'October 13, 2006') returns the string The current date is October 13, 2006.

3.19 COS

COS calculates the cosine of an angle.

Return Value

NUMBER

Syntax

COS(n)

Arguments

n is a numeric expression for an angle represented in radians.

Example

COS(180 * 3.1415927/180) returns the cosine of 180 degrees as the value -1. The expression converts degrees to radians.

3.20 COSH

COSH calculates the cosine of a hyperbolic angle.

Return Value

NUMBER

Syntax

COSH(n)

Arguments

n is a numeric expression for a hyperbolic angle.

Example

COSH(0) returns the value 1.

3.21 CURRENT_DATE

CURRENT_DATE returns the current date in the session time zone.

Return Value

DATE

Syntax

CURRENT_DATE

Example

CURRENT_DATE returns a value such as 12-AUG-08.

3.22 CURRENT_TIMESTAMP

CURRENT_TIMESTAMP returns the current date and time in the session time zone. The time zone offset identifies the current local time of the session.

Return Value

TIMESTAMP WITH TIME ZONE

Syntax

CURRENT_TIMESTAMP [ (precision) ]

Arguments

precision specifies the fractional second precision of the returned time value. The default value is 6.

Examples

CURRENT_TIMESTAMP returns a value such as 08-AUG-06 11.18.31.082257 AM -08:00.

CURRENT_TIMESTAMP(2) returns a value such as 08-AUG-06 11.18.31.08 AM -08:00.

3.23 DBTIMEZONE

DBTIMEZONE returns the value of the database time zone as either a time zone offset from Coordinated Universal Time (UTC) or a time zone region name.

To obtain other time zone offsets, use TZ_OFFSET.

Return Value

VARCHAR2

Syntax

DBTIMEZONE

Example

DBTIMEZONE returns the offset -08:00 for Mountain Standard Time.

3.24 DECODE

DECODE compares an expression to one or more search strings one by one.

If expr is search, then DECODE returns the corresponding result. If there is no match, then DECODE returns default. If you omit default, then DECODE returns NULL.

Return Value

Data type of the first result argument

Syntax

DECODE(expr, search, result
          [, search, result ]...
          [, default ]
      )

Arguments

expr is an expression that is compared to one or more search strings.

search is a string that is searched for a match to expr.

result is the return value when expr matches the corresponding search string.

default is the return value when expr does not match any of the search strings. If default is omitted, then DECODE returns NULL.

The arguments can be any numeric or character type. Two nulls are equivalent. If expr is null, then DECODE returns the result of the first search that is also null.

The maximum number of components, including expr, searches, results, and default, is 255.

Example

DECODE(sysdate, '21-JUN-06', 'Summer Solstice', '21-DEC-06', 'Winter Solstice', 'Have a nice day!')

returns these values:

Summer Solstice on June 21, 2006

Winter Solstice on December 21, 2006

Have a nice day! on all other days

3.25 EXP

EXP returns e raised to the nth power, where e = 2.71828183. The function returns a value of the same type as the argument.

Return Value

NUMBER

Syntax

EXP(n)

Arguments

n is a numeric expression for the exponent.

Example

EXP(4) returns the value 54.59815.

3.26 EXTRACT (datetime)

EXTRACT returns the value of a specified field from a datetime or interval expression.

Return Value

NUMBER

Syntax

EXTRACT( { { YEAR
           | MONTH
           | DAY
           | HOUR
           | MINUTE
           | SECOND
           }
         | { TIMEZONE_HOUR
           | TIMEZONE_MINUTE
           }
         | { TIMEZONE_REGION
           | TIMEZONE_ABBR
           }
         }
    FROM   { datetime_value_expression
           | interval_value_expression
           }
       )

Arguments

datetime_value_expression is an expression with a datetime data type.

interval_value_expression is an expression with an interval data type.

Example

EXTRACT(MONTH FROM CURRENT_TIMESTAMP) returns the value 8 for August when the current timestamp is 08-AUG-06 01.10.55.330120 PM -07:00.

EXTRACT(TIMEZONE_HOUR FROM CURRENT_TIMESTAMP) returns the value -7 from the same example.

3.27 FLOOR

FLOOR returns the largest integer equal to or less than a specified number.

Return Value

NUMBER 

Syntax

FLOOR(n)

Arguments

n can be any numeric expression.

Examples

FLOOR(15.7) returns the value 15.

FLOOR(-15.7) returns the value -16.

3.28 FROM_TZ

FROM_TZ converts a timestamp value and a time zone to a TIMESTAMP WITH TIME ZONE data type.

Return Value

TIMESTAMP WITH TIME ZONE

Syntax

FROM_TZ (timestamp_value, time_zone_value)

Arguments

timestamp_value is an expression with a TIMESTAMP data type.

time_zone_value is a text expression that returns a string in the format TZH:TZM or in TZR with optional TZD format.

Example

FROM_TZ(TIMESTAMP '2008-03-26 08:00:00', '3:00') returns the value 26-MAR-08 08.00.00.000000 AM +03:00.

3.29 GREATEST

GREATEST returns the largest expression in a list of expressions. All expressions after the first are implicitly converted to the data type of the first expression before the comparison. Text expressions are compared character by character.

To retrieve the smallest expression in a list of expressions, use LEAST.

Return Value

The data type of the first expression

Syntax

GREATEST(expr [, expr ]...)

Arguments

expr can be any expression.

Examples

GREATEST('Harry','Harriot','Harold') returns the value Harry.

GREATEST(7, 19, 3) returns the value 19.

3.30 HEXTORAW

HEXTORAW converts a hexadecimal value to a raw value.

Return Value

RAW

Syntax

HEXTORAW (char)

Arguments

char is a hexadecimal value in the CHAR, VARCHAR2, NCHAR, or NVARCHAR2 data type.

Example

HEXTORAW('7D') returns the RAW value 7D.

3.31 INITCAP

INITCAP returns a specified text expression, with the first letter of each word in uppercase and all other letters in lowercase. Words are delimited by white space or non-alphanumeric characters. The data type of the return value is the same as the original text.

Return Value

CHAR | NCHAR | VARCHAR2 | NVARCHAR2

Syntax

INITCAP(char)

Arguments

char can be any text expression.

Example

INITCAP('top ten tunes') and INITCAP('TOP TEN TUNES') both return the string Top Ten Tunes.

3.32 INSTR

The INSTR functions search string for substring. The function returns an integer indicating the position of the character in string, or a zero (0) if does not find a match.

  • INSTR calculates strings using characters as defined by the input character set.

  • INSTRB uses bytes instead of characters.

  • INSTRC uses Unicode complete characters.

REGEXP_INSTR provides additional options.

Return Value

NUMBER

Syntax

{ INSTR | INSTRB | INSTRC }
(string , substring [, position [, occurrence ] ])

Arguments

string is the text expression to search.

substring is the text string to search for.

position is a nonzero integer indicating the character in string where the function begins the search. When position is negative, then INSTR counts and searches backward from the end of string. The default value of position is 1, which means that the function begins searching at the first character of string.

occurrence is an integer indicating which occurrence of string the function should search for. The value of occurrence must be positive. The default values of occurrence is 1, meaning the function searches for the first occurrence of substring.

Example

INSTR('CORPORATE FLOOR','OR', 3, 2) searches the string CORPORATE FLOOR beginning with the third character (R) for the second instance of the substring OR. It returns the value 14, which is the position of the second O in FLOOR.

3.33 LAST_DAY

LAST_DAY returns the last day of the month in which a particular date falls.

Return Value

DATE

Syntax

LAST_DAY(date)

Arguments

date can be any datetime expression.

Example

LAST_DAY('26-MAR-06') returns the value 31-MAR-06.

3.34 LEAST

LEAST returns the smallest expression in a list of expressions. All expressions after the first are implicitly converted to the data type of the first expression before the comparison. Text expressions are compared character by character.

To retrieve the largest expression in a list of expressions, use GREATEST.

Return Value

The data type of the first expression

Syntax

LEAST(expr [, expr ]...)

Arguments

expr can be any expression.

Examples

LEAST('Harry','Harriot','Harold') returns the value Harold.

LEAST(19, 3, 7) returns the value 3.

3.35 LENGTH

The LENGTH functions return the length of a text expression.

  • LENGTH counts the number of characters.

  • LENGTHB uses bytes instead of characters.

  • LENGTHC uses Unicode complete characters.

Return Value

NUMBER

Syntax

{ LENGTH | LENGTHB | LENGTHC }(char)

Arguments

char is any text expression.

Example

LENGTH('CANDIDE') returns the value 7.

3.36 LN

LN returns the natural logarithm of a number greater than 0.

Return Value

NUMBER

Syntax

LN(n)

Arguments

n can be any numeric expression with a value greater than 0.

Example

LN(95) returns the value 4.55387689.

3.37 LNNVL

LNNVL evaluates a condition when one or both operands of the condition may be null. LNNVL can be used anywhere a scalar expression can appear, even in contexts where the IS [NOT] NULL, AND, or OR conditions are not valid but would otherwise be required to account for potential nulls.

NOTE: This function returns 1 (true) if the condition is false or unknown, and 0 (false) if the condition is true.

Return Value

NUMBER

Syntax

LNNVL(condition)

Arguments

condition can be any expression containing scalar values.

Examples

LNNVL(1 > 4) returns 1 (true).

3.38 LOCALTIMESTAMP

LOCALTIMESTAMP returns the current date and time in the session time zone.

Return Value

TIMESTAMP

Syntax

LOCALTIMESTAMP [ (timestamp_precision) ]

Arguments

timestamp_precision specifies the fractional second precision of the time value returned.

Examples

LOCALTIMESTAMP returns a value such as 09-AUG-06 08.11.37.045186 AM.

LOCALTIMESTAMP(2) returns a value such as 09-AUG-06 08.11.37.040000 AM.

3.39 LOG

LOG computes the logarithm of an expression.

Return Value

NUMBER

Syntax

LOG(n2, n1)

Arguments

n2 is the base by which to compute the logarithm.

n1 is the value whose logarithm is calculated. It can be any numeric expression that is greater than zero. When the value is equal to or less than zero, LOG returns a null value.

Example

LOG(10,100) returns the value 2.

3.40 LOWER

LOWER converts all alphabetic characters in a text expression to lowercase. The data type of the return value is the same as the original text.

Return Value

CHAR | NCHAR | VARCHAR2 | NVARCHAR2

Syntax

LOWER(char)

Arguments

char can be any text expression.

Example

LOWER('STOP SHOUTING') returns the string stop shouting.

3.41 LPAD

LPAD adds characters to the left of an expression to a specified length. The data type of the return value is the same as the original text.

Use RPAD to add characters to the right.

Return Value

CHAR | NCHAR | VARCHAR2 | NVARCHAR2

Syntax

LPAD(expr1, n [, expr2 ])

Arguments

expr1 is a text expression for the base string.

n is the total length of the returned expression. If expr1 is longer than n, then this function truncates expr1 to n characters.

expr2 is a text expression for the padding characters. By default, it is a space.

Example

LPAD('Page 1',15,'*.') returns the value *.*.*.*.*Page 1.

LPAD('Stay tuned', 4) returns the value Stay.

3.42 LTRIM

LTRIM scans a text expression from left to right and removes all the characters that match the characters in the trim expression, until it finds an unmatched character. The data type of the return value is the same as the original text.

Return Value

CHAR | NCHAR | VARCHAR2 | NVARCHAR2

Syntax

LTRIM(char [, set ])

Arguments

char is the text expression to be trimmed.

set is a text expression with the characters to remove. The default value of set is a single blank.

Examples

LTRIM(' . . . .Last Word', ' .') returns the value Last Word.

3.43 MOD

MOD returns the remainder after a number is divided by another, or the number if the divisor is 0 (zero).

Return Value

NUMBER

Syntax

MOD(n2, n1)

Arguments

n2 is a numeric expression for the number to be divided.

n1 is a numeric expression for the divisor.

Example

MOD(13,7) returns the value 6.

3.44 MONTHS_BETWEEN

MONTHS_BETWEEN calculates the number of months between two dates. When the two dates have the same day component or are both the last day of the month, then the return value is a whole number. Otherwise, the return value includes a fraction that considers the difference in the days based on a 31-day month.

Return Value

NUMBER

Syntax

MONTHS_BETWEEN(date1, date2)

Arguments

date1 and date2 are datetime expressions. If date1 is later than date2, then the result is positive. If date1 is earlier than date2, then the result is negative.

Example

MONTHS_BETWEEN('15-APR-06', '01-JAN-06') returns the value 3.4516129.

3.45 NANVL

NANVL checks if a value is a number. If it is, then NANVL returns that value. If not, it returns an alternate value. This function is typically used to convert a binary double or binary float NaN (Not a Number) value to zero or null.

Return Value

datatype

Syntax

NANVL (expression, alternate)

Arguments

expression can be any value.

alternate is the numeric value returned if expression is not a number.

3.46 NEW_TIME

NEW_TIME converts the date and time from one time zone to another. Before using this function, set the NLS_DATE_FORMAT parameter to display 24-hour time.

Return Value

DATE

Syntax

NEW_TIME(date, timezone1, timezone2)

Arguments

date is a datetime expression to be converted to a new time zone.

timezone1 is the time zone of date.

timezone2 is the new time zone.

The time zone arguments are limited to the values in Table 3-2. For other time zones, use FROM_TZ.

Table 3-2 Time Zones

Time Zone Abbreviation

Alaska-Hawaii Daylight Time

HDT

Alaska-Hawaii Standard Time

HST

Atlantic Daylight Time

ADT

Atlantic Standard Time

AST

Bering Daylight Time

BDT

Bering Standard Time

BST

Central Daylight Time

CDT

Central Standard Time

CST

Eastern Daylight Time

EDT

Eastern Standard Time

EST

Greenwich Mean Time

GMT

Mountain Daylight Time

MDT

Mountain Standard Time

MST

Newfoundland Standard Time

NST

Pacific Daylight Time

PDT

Pacific Standard Time

PST

Yukon Daylight Time

YDT

Yukon Standard Time

YST

Example

NEW_TIME(SYSDATE, 'PST', 'EST') returns a value such as 18-JAN-07 04:38:07 in Eastern Standard Time when SYSDATE is 18-JAN-07 01:38:07 in Pacific Standard Time. For this example, NLS_DATE_FORMAT is set to DD-MON-RR HH:MI:SS.

3.47 NEXT_DAY

NEXT_DAY returns the date of the first instance of a particular day of the week that follows the specified date.

Return Value

DATE

Syntax

NEXT_DAY(date, char)

Arguments

date is a datetime expression.

char is a text expression that identifies a day of the week (for example, Monday) in the language of your session.

Example

NEXT_DAY('11-SEP-01', 'Monday') returns the value 17-SEP-01.

3.48 NLS_CHARSET_ID

NLS_CHARSET_ID returns the identification number corresponding to a specified character set name.

Return Value

NUMBER

Syntax

NLS_CHARSET_ID  ( charset_name )

Arguments

charset_name is a VARCHAR2 expression that is a valid character set name.

Example

NLS_CHARSET_ID('AL32UTF8') returns the value 873.

3.49 NLS_CHARSET_NAME

NLS_CHARSET_NAME returns the name corresponding to a specified character set number.

Return Value

VARCHAR2

Syntax

NLS_CHARSET_NAME (charset_id)

Arguments

charset_id is a valid character set number or one of these keywords:

  • CHAR_CS represents the database character set.

  • NCHAR_CS represents the national character set. The national character set for the database can be either UTF-8 or AL16UTF16 (default). However, the national character set for analytic workspaces is always UTF-8.

If the number does not correspond to a character set, then the function returns NULL.

Example

NLS_CHARSET_NAME(2000) returns the value AL16UTF16.

3.50 NLS_INITCAP

NLS_INITCAP returns a string in which each word begins with a capital followed by lower-case letters. White space and nonalphanumeric characters delimit the words.

Return Value

VARCHAR2

Syntax

NLS_INITCAP (char [, 'nlsparam' ])

Arguments

char can be any text string.

nlsparam can have the form 'NLS_SORT =sort' where sort is either a linguistic sort sequence or BINARY. The linguistic sort sequence handles special linguistic requirements for case conversions. These requirements can result in a return value of a different length than char. If you omit nlsparam, then this function uses the default sort sequence for your session.

Example

NLS_INITCAP('WALKING&THROUGH*A*winter wonderland') returns the value Walking#Through*A*Winter Wonderland.

NLS_INITCAP('ijsland') returns the value Ijsland, but NLS_INITCAP(NLS_INITCAP('ijsland', 'NLS_SORT = XDutch') returns IJsland.

3.51 NLS_LOWER

NLS_LOWER converts all alphabetic characters in a text expression to lowercase. The data type of the return value is the same as the original text.

Return Value

CHAR | NCHAR | VARCHAR2 | NVARCHAR2

Syntax

NLS_LOWER (char [, 'nlsparam' ])

Arguments

char can be any text expression.

nlsparam is a linguistic sort sequence in the form NLS_SORT =sort[_ai |_ci], where sort is an NLS language. You can add a suffix to the language to modify the sort: _ai for an accent-insensitive sort, or _ci for a case-insensitive sort.

Example

NLS_LOWER('STOP SHOUTING') returns the string stop shouting.

3.52 NLS_UPPER

NLS_UPPER converts all alphabetic characters in a text expression to uppercase. The data type of the return value is the same as the original text.

Return Value

CHAR | NCHAR | VARCHAR2 | NVARCHAR2

Syntax

NLS_UPPER (char [, 'nlsparam' ])

Arguments

char can be any text expression.

nlsparam is a linguistic sort sequence in the form NLS_SORT =sort[_ai |_ci], where sort is an NLS language. You can add a suffix to the language to modify the sort: _ai for an accent-insensitive sort, or _ci for a case-insensitive sort.

Example

NLS_UPPER('This is an emergency') returns the string THIS IS AN EMERGENCY.

3.53 NLSSORT

NLSSORT returns the string of bytes used to sort a text string. You can use this function to specify sorting and comparison operations based on a linguistic sort sequence rather than on the binary value of a string.

Note: NLSSORT returns a RAW value, which you may pass to another function. To create a measure or a calculated measure for the values returned by NLSSORT, use the RAWTOHEX function.

For more information about linguistic sorting, refer to the Oracle Database Globalization Support Guide.

Return Value

RAW

Syntax

NLSSORT(char [, 'nlsparam' ])

Arguments

char is a text expression.

nlsparam is a linguistic sort sequence in the form NLS_SORT =sort[_ai |_ci], where sort is an NLS language. You can add a suffix to the language to modify the sort: _ai for an accent-insensitive sort, or _ci for a case-insensitive sort.

Example

NLSSORT('Rumpelstiltskin') returns the value 52756D70656C7374696C74736B696E00 for a default linguistic sort, which in this case is American.

3.54 NULLIF

NULLIF compares one expression with another. It returns NULL when the expressions are equal, or the first expression when they are not.

Return Value

Data type of the first argument

Syntax

NULLIF(expr1, expr2)

Arguments

expr1 is the base expression. It cannot be a literal null.

expr2 is the expression to compare with the base expression.

Example

NULLIF('red', 'Red') returns the value red.

3.55 NUMTODSINTERVAL

NUMTODSINTERVAL converts a number to an INTERVAL DAY TO SECOND data type.

Return Value

INTERVAL DAY TO SECOND

Syntax

NUMTODSINTERVAL(n, 'interval_unit')

Arguments

n can be any numeric expression.

interval_unit is a text expression that specifies the units. It must resolve to one of the following values:

  • DAY

  • HOUR

  • MINUTE

  • SECOND

These values are case insensitive.

Example

NUMTODSINTERVAL(100, 'MINUTE') returns the value +00 01:40:00.000000.

3.56 NUMTOYMINTERVAL

NUMTOYMINTERVAL converts a number to an INTERVAL YEAR TO MONTH data type.

Return Value

INTERVAL YEAR TO MONTH

Syntax

NUMTOYMINTERVAL(n, 'interval_unit')

Arguments

n can be any numeric expression.

interval_unit is a text expression that specifies the units. It must resolve to one of the following values:

  • YEAR

  • MONTH

These values are case insensitive.

Example

NUMTOYMINTERVAL(18, 'MONTH') returns the value +01-06.

3.57 NVL

NVL replaces a null with a string. NVL returns the replacement string when the base expression is null, and the value of the base expression when it is not null.

To replace an expression with one value if it is null and a different value if it is not, use NVL2.

Return Value

Data type of the first argument

Syntax

NVL(expr1, expr2)

Arguments

expr1 is the base expression that is evaluated.

expr2 is the replacement string that is returned when expr1 is null.

Examples

NVL('First String', 'Second String') returns the value First String.

NVL(null, 'Second String') returns the value Second String.

3.58 NVL2

NVL2 returns one value when the value of a specified expression is not null, or another value when the value of the specified expression is null.

To replace a null value with a string, use NVL.

Return Value

Data type of the first argument

Syntax

NVL2(expr1, expr2, expr3)

Arguments

expr1 is the base expression whose value this function evaluates.

expr2 is an expression whose value is returned when expr1 is not null.

expr3 is an expression whose value is returned when expr1 is null.

Example

NVL2('Which string?', 'First String', 'Second String') returns the value First String.

3.59 ORA_HASH

ORA_HASH generates hash values for an expression. You can use it to randomly assign a set of values into several buckets for analysis, or to generate a set of random numbers.

Return Value

NUMBER

Syntax

ORA_HASH  (expr [, max_bucket [, seed_value ] ])

Arguments

expr can be any expression that provides the data for generating the hash values.

max_bucket is the maximum bucket number. For example, when max_bucket is set to 5, ORA_HASH returns values of 0 to 5, creating six buckets. Set this value from 0 to 4294967295 or 2^32-1 (default).

seed_value is a value used by ORA_HASH to generate the hash values. Enter a different seed_value for different results. Set this value from 0 (default) to 4294967295 or 2^32-1.

Example

ORA_HASH(PRODUCT_CUBE.PRICES, 5) returns a value in the range of 0 to 5 for each value of the Prices measure, as shown in the Hash 5 column. The rows are also sorted on the Hash 5 column.

ORA_HASH(PRODUCT_CUBE.PRICES, 5, 13) also returns values in the range of 0 to 5, but uses a different seed.

Product Prices Hash 5 Seed 13

ENVY STD

200539.83

0

4

ENVY EXE

255029.31

0

5

1GB USB DRV

44645.65

1

2

DLX MOUSE

1379.49

2

2

144MB DISK

3011.43

2

5

512 USB DRV

22139.99

2

2

19 SVGA

34837.16

3

0

56KPS MODEM

12478

3

2

ENVY EXT KBD

4312.22

3

5

17 SVGA

22605.55

4

1

EXT CD ROM

17990.14

4

0

ENVY ABM

205462.25

5

1

3.60 POWER

POWER raises a number to a power.

Return Value

NUMBER

Syntax

POWER(n2, n1)

Arguments

n2 is any numeric expression that is raised to a power.

n1 is the exponent.

Example

POWER(3,2) returns the value 9.

3.61 RAWTOHEX

RAWTOHEX converts raw data to a character value containing its hexadecimal representation.

Return Value

VARCHAR2

Syntax

RAWTOHEX(raw)

Arguments

raw can be any scalar data type other than LONG, LONG RAW, CLOB, BLOB, or BFILE.

Example

RAWTOHEX(NLSSORT('Rumpelstiltskin')) converts the raw value returned by NLSSORT to the hexadecimal value 52756D70656C7374696C74736B696E00.

3.62 REGEXP_COUNT

REGEXP_COUNT searches a string for a regular pattern and returns the number of times the pattern occurs. If no match is found, the function returns 0.

The function evaluates strings using characters as defined by the input character set.

Return Value

NUMBER

Syntax

REGEXP_COUNT (source_char, pattern
              [, position
                 [, match_parameter ]
              ]
             )

Arguments

source_char is the text expression to search.

pattern is the string to search for. A period matches any character. For a list of operators, refer to the Oracle Database SQL Language Reference, Appendix D, "Oracle Regular Expression Support."

position is a nonzero integer indicating the character of source_char where the function begins the search. When position is negative, then the function counts and searches backward from the end of string. The default value of position is 1, which means that the function begins searching at the first character of source_char.

match_parameter is a text literal that lets you change the default matching behavior of the function. You can specify one or more of the following values:

  • c: Case-sensitive matching.

  • i: Case-insensitive matching.

  • m: Treat the source string as multiple lines. The function interprets ^ and $ as the start and end, respectively, of any line anywhere in the source string, rather than only at the start or end of the entire source string. By default, the function treats the source string as a single line.

  • n: New-line character is among the characters matched by a period (the wildcard character). By default, it is not.

  • x: Ignore whitespace characters.

Example

REGEXP_COUNT('Mississippi', 'i', 1) searches the string Mississippi for the letter i, beginning the search at the first letter. It returns the value 4.

3.63 REGEXP_REPLACE

REGEXP_REPLACE searches a string for a regular pattern and replaces it with another string. By default, the function returns source_char with every occurrence of the regular expression pattern replaced with replace_string.

Return Value

CHAR | NCHAR | VARCHAR2 | NVARCHAR2

Syntax

REGEXP_REPLACE(source_char, pattern
               [, replace_string
                  [, position
                     [, occurrence
                        [, match_parameter ]
                     ]
                  ]
               ]
              )

Arguments

source_char is the text expression that is searched.

pattern is the text expression to search for. It is usually a text literal and can contain up to 512 bytes. For a list of operators, refer to the Oracle Database SQL Language Reference, Appendix D, "Oracle Regular Expression Support."

replace_string is the text that replaces pattern in source_char.

position is a nonzero integer indicating the character of source_char where the function begins the search. When position is negative, then the function counts and searches backward from the end of string. The default value of position is 1, which means that the function begins searching at the first character of source_char.

occurrence is an integer indicating which occurrence of pattern the function should search for. The value of occurrence must be positive. The default values of occurrence is 1, meaning the function searches for the first occurrence of pattern.

match_parameter is a text literal that lets you change the default matching behavior of the function. You can specify one or more of the following values:

  • c: Case-sensitive matching.

  • i: Case-insensitive matching.

  • m: Treat the source string as multiple lines. The function interprets ^ and $ as the start and end, respectively, of any line anywhere in the source string, rather than only at the start or end of the entire source string. By default, the function treats the source string as a single line.

  • n: New-line character is among the characters matched by a period (the wildcard character). By default, it is not.

  • x: Ignore whitespace characters.

Example

REGEXP_REPLACE('500 Oracle Parkway, Redwood Shores, CA', '( ){2,}', ' ')

eliminates extra spaces and returns the string

500 Oracle Parkway, Redwood Shores, CA

3.64 REGEXP_INSTR

REGEXP_INSTR searches a string for a regular pattern. It can return an integer indicating either the beginning or the ending position of the matched substring. If no match is found, then the function returns 0.

The function evaluates strings using characters as defined by the input character set.

Return Value

NUMBER

Syntax

REGEXP_INSTR (source_char, pattern
              [, position
                 [, occurrence
                    [, return_option
                       [, match_parameter ]
                    ]
                 ]
              ]
             )

Arguments

source_char is the text expression to search.

pattern is the string to search for. A period matches any character. For a list of operators, refer to the Oracle Database SQL Language Reference, Appendix D, Oracle Regular Expression Support.

position is a nonzero integer indicating the character of source_char where the function begins the search. When position is negative, then the function counts and searches backward from the end of string. The default value of position is 1, which means that the function begins searching at the first character of source_char.

occurrence is an integer indicating which occurrence of pattern the function should search for. The value of occurrence must be positive. The default values of occurrence is 1, meaning the function searches for the first occurrence of pattern.

return_option is either 0 to return the position of the match (default), or 1 to return the position of the character following the match.

match_parameter is a text literal that lets you change the default matching behavior of the function. You can specify one or more of the following values:

  • c: Case-sensitive matching.

  • i: Case-insensitive matching.

  • m: Treat the source string as multiple lines. The function interprets ^ and $ as the start and end, respectively, of any line anywhere in the source string, rather than only at the start or end of the entire source string. By default, the function treats the source string as a single line.

  • n: New-line character is among the characters matched by a period (the wildcard character). By default, it is not.

  • x: Ignore whitespace characters.

Example

REGEXP_INSTR('Mississippi', 'i', 1, 3) searches the string Mississippi for the third instance of the letter i, beginning the search at the first letter. It returns the value 8.

3.65 REGEXP_SUBSTR

REGEXP_SUBSTR searches a string for a pattern and returns the matching string.

Return Value

CHAR | NCHAR | VARCHAR2 | NVARCHAR

Syntax

REGEXP_SUBSTR(source_char, pattern
              [, position
                 [, occurrence
                    [, match_parameter ]
                 ]
              ]
             )

Arguments

source_char is the text expression that is searched.

pattern is the text expression to search for. It is usually a text literal and can contain up to 512 bytes. For a list of operators, refer to the Oracle Database SQL Language Reference, Appendix D, "Oracle Regular Expression Support."

position is a nonzero integer indicating the character of source_char where the function begins the search. When position is negative, then the function counts and searches backward from the end of string. The default value of position is 1, which means that the function begins searching at the first character of source_char.

occurrence is an integer indicating which occurrence of pattern the function should search for. The value of occurrence must be positive. The default values of occurrence is 1, meaning the function searches for the first occurrence of pattern.

match_parameter is a text expression that lets you change the default matching behavior of the function. You can specify one or more of the following values:

  • c: Case-sensitive matching.

  • i: Case-insensitive matching.

  • m: Treat the source string as multiple lines. The function interprets ^ and $ as the start and end, respectively, of any line anywhere in the source string, rather than only at the start or end of the entire source string. By default, the function treats the source string as a single line.

  • n: New-line character is among the characters matched by a period (the wildcard character). By default, it is not.

  • x: Ignore whitespace characters.

Examples

REGEXP_SUBSTR('7 W 96th St, New York, NEW YORK', 'new york', 10, 2, 'i') starts searching at the tenth character and matches NEW YORK in a case-insensitive match.

REGEXP_SUBSTR('parsley, sage, rosemary, thyme', 's[^,]+e', 1, 2) starts searching at the first character and matches the second substring consisting of the letter s, any number of characters that are not commas, and the letter e. In this example, the function returns the value sage.

3.66 REMAINDER

REMAINDER returns a rounded remainder when one number is divided by another using this equation:

n2 - (n1 * N)

where N is the integer nearest n2/n1.

Return Value

NUMBER

Syntax

REMAINDER(n2, n1)

Arguments

n1 is a numeric expression for the divisor.

n2 is a numeric expression for the dividend.

Example

REMAINDER(18,7) returns the value -3.

3.67 REPLACE

REPLACE searches a string for a regular pattern, replaces it with another string, and returns the modified string.

Return Value

CHAR | NCHAR | VARCHAR2 | NVARCHAR2

Syntax

REPLACE(char, search_string [, replacement_string ])

Arguments

char is the text expression that is searched.

search_string is the text expression to search for.

replacement_string is the text expression that replaces search_string in char.

Example

REPLACE('Nick Nack', 'N', 'Cl') returns the string Click Clack.

3.68 ROUND (date)

ROUND returns a date rounded to the unit specified by the date format.

Return Value

DATE

Syntax

ROUND(date [, fmt ])

Arguments

date is an expression that identifies a date and time.

fmt is a text literal with a date format, as described in the Oracle Database SQL Language Reference.

Examples

ROUND(SYSDATE, 'YEAR') returns the value 01-JAN-07 for any day in the last half of 2006.

ROUND(TO_DATE('13-OCT-06'), 'MONTH') returns the value 01-OCT-06.

3.69 ROUND (number)

ROUND returns a number rounded to a specified number of places.

Return Value

NUMBER

Syntax

ROUND(n [, integer ])

Arguments

n is the number to round.

integer is the number of decimal places of the rounded number. A negative value rounds to the left of the decimal point. The default value is 0.

Examples

ROUND(15.193) returns the value 15.

ROUND(15.193,1) returns the value 15.2.

ROUND(15.193,-1) returns the value 20.

3.70 ROWIDTOCHAR

ROWIDTOCHAR converts a row address from a ROWID data type to text.The return value is always 18 characters long in the database character set.

Return Value

VARCHAR2

Syntax

ROWIDTOCHAR(rowid)

Arguments

rowid is a row address to convert.

3.71 ROWIDTONCHAR

ROWIDTONCHAR converts a row address from the ROWID data type to text. The return value is always 18 characters in the national character set.

Return Value

NVARCHAR2

Syntax

ROWIDTONCHAR(rowid)

Arguments

rowid is a row address to convert.

3.72 RPAD

RPAD adds characters to the right of an expression to a specified length. The data type of the return value is the same as the original text.

Use LPAD to add characters to the left.

Return Value

CHAR | NCHAR | VARCHAR2 | NVARCHAR2

Syntax

RPAD(expr1 , n [, expr2 ])

Arguments

expr1 is a text expression for the base string.

n is the total length of the returned expression. If expr1 is longer than n, then this function truncates expr1 to n characters.

expr2 is a text expression for the padding characters. By default, it is a space.

Example

RPAD('Stay tuned', 15, '. ') returns the value Stay tuned. . .

RPAD('Stay tuned', 4) returns the value Stay.

3.73 RTRIM

RTRIM scans a text expression from right to left and removes all the characters that match the characters in the trim expression, until it finds an unmatched character. The data type of the return value is the same as the original text.

Return Value

CHAR | NCHAR | VARCHAR2 | NVARCHAR2

Syntax

RTRIM(char [, set ])

Arguments

char is the text expression to be trimmed.

set is a text expression with the characters to remove. The default value of set is a single blank.

Examples

RTRIM('You did that!?!?!?!', '?!') returns the value You did that.

RTRIM('3.14848', '84') returns the text value 3.1.

3.74 SESSIONTIMEZONE

SESSIONTIMEZONE returns the time zone of the current session. The return type is a time zone offset from Coordinated Universal Time (UTC) or a time zone region name.

Return Value

VARCHAR2

Syntax

SESSIONTIMEZONE

Example

SESSIONTIMEZONE returns the value -05:00 for Eastern Standard Time.

3.75 SIGN

SIGN returns a value that indicates whether a specified number is less than, equal to, or greater than 0 (zero):

  • -1 if n < 0

  • 0 if n = 0

  • 1 if n > 0

Return Value

NUMBER

Syntax

SIGN(n)

Arguments

n is a numeric expression.

Example

SIGN(-15) returns the value -1.

3.76 SIN

SIN returns the sine of an angle.

Return Value

NUMBER

Syntax

SIN(n)

Arguments

n is a numeric expression for an angle in radians.

Example

SIN(30 * 3.1415927/180) calculates the sine of a 30 degrees angle as the value 0.500000007. The numeric expression converts degrees to radians.

3.77 SINH

SINH returns the sine of a hyperbolic angle.

Return Value

NUMBER

Syntax

SINH(n)

Arguments

n is a numeric expression for a hyperbolic angle.

Example

SINH(1) returns the value 1.17520119.

3.78 SOUNDEX

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

The function is based on the algorithm described in Donald Knuth's The Art of Computer Programming. This algorithm was designed specifically for English. Its results for other languages other than English are unpredictable and typically unsatisfactory.

Return Value

VARCHAR2

Syntax

SOUNDEX (char)

Arguments

char can be any text expression.

Example

All of these examples return the value D500:

soundex('Donna')

soundex('Diane')

soundex('Dana')

3.79 SQRT

SQRT returns the square root of a number.

Return Value

NUMBER

Syntax

SQRT(n)

Arguments

n is a numeric expression for a positive number.

Example

SQRT(13) returns the value 3.60555128.

3.80 SUBSTR

SUBSTR returns a portion of string, beginning at a specified character position and extending a specified number of characters.

  • SUBSTR calculates lengths using characters as defined by the input character set.

  • SUBSTRB uses bytes instead of characters.

  • SUBSTRC uses Unicode complete characters.

Return Value

CHAR | NCHAR | VARCHAR2 | NVARCHAR2

Syntax

{ SUBSTR | SUBSTRB | SUBSTRC }(char, position [, substring_length ])

Arguments

char is a text expression that provides the base string from which the substring is derived.

position identifies the first character of the substring:

  • When position is positive, then the function counts from the beginning of char to find the first character.

  • When position is negative, then the function counts backward from the end of char.

  • When position is 0 (zero), then the first character is the beginning of the substring.

substring_length is the number of characters in the returned string. By default, the function returns all characters to the end of the base string. If you specify a value less than 1, then the function returns a null.

Examples

SUBSTR('firefly', 1, 4) returns the substring fire.

SUBSTR('firefly', -3, 3) returns the substring fly.

3.81 SYS_CONTEXT

SYS_CONTEXT returns the value of an attribute of a named context. The context, attribute, and value must already be defined in the database. If the context is not defined, SYS_CONTEXT returns NULL.

Return Value

VARCHAR2

Syntax

SYS_CONTEXT ('namespace', 'parameter')

Arguments

namespace can be any named context in the database. USERENV is a built-in context that describes the current session.

parameter is a defined attribute of namespace. Table 3-3 describes the predefined attributes of USERENV that are most likely to have values. For a complete list, refer to the SYS_CONTEXT entry in the Oracle Database SQL Language Reference.

Table 3-3 USERENV Attributes

USERENV Attribute Description

AUTHENTICATED_IDENTITY

The identity used for authentication, such as database user name, schema name, or operating system login name.

AUTHENTICATION_METHOD

The method of authentication, such as PASSWORD, OS, or SSL.

CURRENT_EDITION_ID

The session edition identifier, such as 100.

CURRENT_EDITION_NAME

The session edition name, such as ORA$BASE.

CURRENT_SCHEMA

The name of the currently active default schema, such as SH.

CURRENT_SCHEMA_ID

The numeric identifier of the currently active default schema, such as 80.

CURRENT_USER

The name of the database user whose privileges are currently active, such as SH.

CURRENT_USERID

The numeric identifier of the database user whose privileges are currently active, such as 80.

DATABASE_ROLE

Data Guard role of the database: PRIMARY, PHYSICAL STANDBY, LOGICAL STANDBY, or SNAPSHOT STANDBY.

DB_DOMAIN

The network domain of the database as specified by the DB_DOMAIN initialization parameter, such as us.example.com.

DB_NAME

The name of the database as specified by the DB_NAME initialization parameter.

DB_UNIQUE_NAME

The unique name of the database within the domain as specified by the DB_UNIQUE_NAME initialization parameter.

ENTERPRISE_IDENTITY

The enterprise-wide identity of the user, or NULL for local users, SYSDBA, and SYSOPER.

FG_JOB_ID

Job identifier of the current session if a client foreground process opened it; otherwise, NULL.

GLOBAL_CONTEXT_MEMORY

The number used in the System Global Area by the globally accessed context.

GLOBAL_UID

The global user identification from Oracle Internet Directory for Enterprise User Security logins; otherwise, NULL.

HOST

The name of the client host computer.

IDENTIFICATION_TYPE

The way the user schema was created in the database: LOCAL, EXTERNAL, GLOBAL SHARED, or GLOBAL PRIVATE.

INSTANCE

The identification number of the current instance, such as 1.

INSTANCE_NAME

The name of the database instance.

IP_ADDRESS

The IP address of the client, such as 10.255.255.255.

ISDBA

TRUE if the user was authenticated with DBA privileges; otherwise, FALSE.

LANG

A short name for the session language, such as US for AMERICAN.

LANGUAGE

The language, territory, and database character set in the form language_territory.characterset, such as AMERICA_AMERICAN.WE8DEC.

MODULE

The application name set through the DBMS_APPLICATION_INFO package or OCI, such as JDBC Thin Client or SQL Developer.

NETWORK_PROTOCOL

The network protocol being used for communication, such as TCP.

NLS_CALENDAR

The session calendar, such as GREGORIAN.

NLS_CURRENCY

The session currency mark, such as $.

NLS_DATE_FORMAT

The session date format, such as DD-MON-RR.

NLS_DATE_LANGUAGE

The session date language, such as AMERICAN.

NLS_SORT

BINARY or a linguistic sort basis, such as XSPANISH.

NLS_TERRITORY

The session territory, such as AMERICA.

OS_USER

The operating system user name of the client process that initiated the database session.

SERVER_HOST

The host name of the computer where the database instance is running.

SERVICE_NAME

The name of the service the session is connected to, such as SYS$USERS.

SESSION_USER

The database user name or schema name that identified the user at login, such as SH.

SESSIONID

The session identifier, such as 120456.

SID

The session number, such as 86.

Example

SYS_CONTEXT('USERENV','NLS_DATE_FORMAT') returns a value such as DD-MON-RR.

3.82 SYSDATE

SYSDATE returns the current date and time of the operating system on which the database resides. The format of the value depends on the value of the NLS_DATE_FORMAT initialization parameter.

Return Value

DATE

Syntax

SYSDATE

Examples

SYSDATE returns a value such as 13-AUG-06 with NLS_DATE_FORMAT set to DD-MON-RR.

TO_CHAR(SYSDATE, 'MM-DD-YYYY HH24:MI:SS') returns a value such as 08-13-2006 17:20:47. The date format provided in the call to TO_CHAR displays both the date and the time.

3.83 SYSTIMESTAMP

SYSTIMESTAMP returns the system date, including fractional seconds and time zone, of the system on which the database resides.

Return Value

TIMESTAMP WITH TIME ZONE

Syntax

SYSTIMESTAMP

Example

SYSTIMESTAMP returns a value such as

13-AUG-06 05.28.10.385799 PM -08:00.

3.84 TAN

TAN returns the tangent of an angle.

Return Value

NUMBER

Syntax

TAN(n)

Arguments

n is a numeric expression for an angle in radians.

Example

TAN(135 * 3.1415927/180) calculates the tangent of a 135 degree angle as the value -0.99999993. The expression converts degrees to radians.

3.85 TANH

TANH returns the tangent of a hyperbolic angle.

Return Value

NUMBER

Syntax

TANH(n)

Arguments

n is a numeric expression for a hyperbolic angle.

Example

TANH(.5) returns the value 0.462117157.

3.86 TO_BINARY_DOUBLE

TO_BINARY_DOUBLE converts a text or numeric expression to a double-precision floating-point number.

Return Value

BINARY_DOUBLE

Syntax

TO_BINARY_DOUBLE (expr [, fmt [, 'nlsparam' ] ])

Arguments

n can be any text or numeric expression.

fmt is a text expression that identifies a number format model as described in the Oracle Database SQL Language Reference.

nlsparam specifies the characters used by these number format elements:

  • Decimal character

  • Group separator

  • Local currency symbol

  • International currency symbol

This argument has the format shown here:

'NLS_NUMERIC_CHARACTERS = ''dg''
 NLS_CURRENCY = ''text''
 NLS_ISO_CURRENCY = territory '

The d is the decimal character, and the g is the group separator. They must be different single-byte characters. Within the quoted string, use two single quotation marks around the parameter values. Ten characters are available for the currency symbol.

If you omit this argument or any of the NLS parameters, then this function uses the default values for your session to interpret expr.

Example

All of these examples return the value 1.235E+003:

TO_BINARY_DOUBLE(1234.56)

TO_BINARY_DOUBLE('$1,234.56', '$9,999.99')

TO_BINARY_DOUBLE('1.234,56', '9G999D99', 'NLS_NUMERIC_CHARACTERS='',.''')

3.87 TO_BINARY_FLOAT

TO_BINARY_FLOAT converts a text or numeric expression to a single-precision floating-point number.

Return Value

BINARY_FLOAT

Syntax

TO_BINARY_FLOAT (expr [, fmt [, 'nlsparam' ] ])

Arguments

n can be any text or numeric expression.

fmt is a text expression that identifies a number format model as described in the Oracle Database SQL Language Reference.

nlsparam specifies the characters used by these number format elements:

  • Decimal character

  • Group separator

  • Local currency symbol

  • International currency symbol

This argument has the format shown here:

'NLS_NUMERIC_CHARACTERS = ''dg''
 NLS_CURRENCY = ''text''
 NLS_ISO_CURRENCY = territory '

The d is the decimal character, and the g is the group separator. They must be different single-byte characters. Within the quoted string, use two single quotation marks around the parameter values. Ten characters are available for the currency symbol.

If you omit this argument or any of the NLS parameters, then this function uses the default values for your session to interpret expr.

Examples

All of these examples return the value 1.235E+003:

TO_BINARY_FLOAT(1234.56)

TO_BINARY_FLOAT('$1,234.56', '$9,999.99')

TO_BINARY_FLOAT('1.234,56', '9G999D99', 'NLS_NUMERIC_CHARACTERS='',.''')

3.88 TO_CHAR (character)

TO_CHAR(character) converts a text expression to the database character set.

Return Value

VARCHAR2

Syntax

TO_CHAR(exp)

Arguments

char is a text expression. If it contains characters that are not represented in the database character set, then the conversion results in a loss of data.

Examples

TO_CHAR('¡Una qué sorpresa!') returns the value ?Una qu? sorpresa! Two letters are lost in the conversion (¡and é) because they are not in the database character set.

TO_CHAR('David Ortiz') returns the value David Ortiz in the database character set. No characters are lost in this conversion because all of them are in the database character set.

3.89 TO_CHAR (datetime)

TO_CHAR(datetime) converts a datetime or interval expression to a text string in a specified format.

Return Value

VARCHAR2

Syntax

TO_CHAR({ datetime | interval } [, fmt [, 'nlsparam' ] ])

Arguments

datetime is a datetime expression to be converted to text.

interval is an interval expression to be converted to text.

fmt is a datetime model format specifying the format of char. The default date format is determined implicitly by the NLS_TERRITORY initialization parameter or can be set explicitly by the NLS_DATE_FORMAT parameter. For data type formats, refer to the Oracle Database SQL Language Reference.

nlsparam specifies the language in which month and day names and abbreviations are returned. This argument can have this form:

'NLS_DATE_LANGUAGE = language' 

By default, the return value is in the session date language.

Examples

TO_CHAR(SYSDATE) returns a value such as 11-APR-08.

TO_CHAR(SYSDATE, 'Day: MONTH DD, YYYY') returns a value such as Friday : APRIL 11, 2008.

TO_CHAR(SYSDATE, 'Day: MONTH DD, YYYY', 'NLS_DATE_LANGUAGE = Spanish') returns a value such as Viernes : ABRIL 11, 2008.

3.90 TO_CHAR (number)

TO_CHAR(number) converts a numeric expression to a text value in the database character set.

Return Value

VARCHAR2

Syntax

TO_CHAR(n [, fmt [, 'nlsparam' ] ])

Arguments

n is a numeric expression to be converted.

fmt is a text expression that identifies a number format model as described in the Oracle Database SQL Language Reference.

nlsparam specifies the characters that are returned by these number format elements:

  • Decimal character

  • Group separator

  • Local currency symbol

  • International currency symbol

This argument has the format shown here:

'NLS_NUMERIC_CHARACTERS = ''dg''
 NLS_CURRENCY = ''text''
 NLS_ISO_CURRENCY = territory '

The characters d and g represent the decimal character and group separator, respectively. They must be different single-byte characters. Within the quoted string, use two single quotation marks around the parameter values. Ten characters are available for the currency symbol.

If you omit this argument or any of the NLS parameters, then this function uses the default values for your session.

Examples

TO_CHAR(1234567, 'C9G999G999D99') returns a text string such as USD1,234,567.00.

TO_CHAR(1234567, 'C9G999G999D99', 'NLS_ISO_CURRENCY = SPAIN') returns the text string EUR1,234,567.00.

3.91 TO_DATE

TO_DATE converts a text expression to a DATE data type.

Return Value

DATE

Syntax

TO_DATE(char [, fmt [, 'nlsparam' ] ])

Arguments

char is a text expression that represents a date.

fmt is a datetime model format specifying the format of char. The default date format is determined implicitly by the NLS_TERRITORY initialization parameter or can be set explicitly by the NLS_DATE_FORMAT parameter. For data type formats, refer to the Oracle Database SQL Language Reference.

nlsparam specifies the language of char. This argument can have this form:

'NLS_DATE_LANGUAGE = language' 

By default, char is in the session date language.

Examples

TO_DATE('October 13, 2008', 'MONTH DD, YYYY') returns the value 13-OCT-08.

TO_DATE('13 Octubre 2008', 'dd month yyyy', 'NLS_DATE_LANGUAGE=SPANISH') also returns the value 13-OCT-08

3.92 TO_DSINTERVAL

TO_DSINTERVAL converts a text expression to an INTERVAL DAY TO SECOND data type.

Return Value

INTERVAL DAY TO SECOND

Syntax

TO_DSINTERVAL(char)

Arguments

char is a text expression to be converted.

Example

TO_DSINTERVAL('360 12:45:49') returns the value +360 12:45:49.000000.

3.93 TO_NCHAR (character)

TO_NCHAR(character) converts a character string to the national character set.

Return Value

NVARCHAR2

Syntax

TO_NCHAR(exp)

Arguments

exp is a text expression. If it contains characters that are not represented in the national character set, then the conversion results in a loss of data.

Example

TO_NCHAR('David Ortiz') returns the value David Ortiz in the national character set.

3.94 TO_NCHAR (datetime)

TO_NCHAR(datetime) converts a datetime or interval value to the national character set.

Return Value

NVARCHAR2

Syntax

TO_NCHAR({ datetime | interval }
         [, fmt [, 'nlsparam' ] ]
        )

Arguments

datetime is a datetime expression to be converted to text.

interval is an interval expression to be converted to text.

fmt is a datetime model format specifying the format of char. The default date format is determined implicitly by the NLS_TERRITORY initialization parameter or can be set explicitly by the NLS_DATE_FORMAT parameter. For data type formats, refer to the Oracle Database SQL Language Reference.

nlsparam specifies the language in which month and day names and abbreviations are returned. This argument can have this form:

'NLS_DATE_LANGUAGE = language' 

By default, the return value is in the session date language.

Examples

TO_NCHAR(SYSDATE) returns a value such as 11-APR-08.

TO_NCHAR(SYSDATE, 'Day: MONTH DD, YYYY') returns a value such as Friday : APRIL 11, 2008.

TO_NCHAR(SYSDATE, 'Day: MONTH DD, YYYY', 'NLS_DATE_LANGUAGE = Spanish') returns a value such as Viernes : ABRIL 11, 2008.

3.95 TO_NCHAR (number)

TO_NCHAR(number) converts a number to the national character set.

Return Value

NVARCHAR2

Syntax

TO_CHAR(n [, fmt [, 'nlsparam' ] ])

Arguments

n is a numeric expression to be converted.

fmt is a text expression that identifies a number format model as described in the Oracle Database SQL Language Reference.

nlsparam is a text expression that specifies the characters that are returned by these number format elements:

  • Decimal character

  • Group separator

  • Local currency symbol

  • International currency symbol

This argument has the format shown here:

'NLS_NUMERIC_CHARACTERS = ''dg''
   NLS_CURRENCY = ''text''
   NLS_ISO_CURRENCY = territory '

The characters d and g represent the decimal character and group separator, respectively. They must be different single-byte characters. Within the quoted string, use two single quotation marks around the parameter values. Ten characters are available for the currency symbol.

If you omit this argument or any of the NLS parameters, then this function uses the default values for your session.

Examples

TO_NCHAR(1234567, 'C9G999G999D99') returns a text string such as USD1,234,567.00.

TO_NCHAR(1234567, 'C9G999G999D99', 'NLS_ISO_CURRENCY = SPAIN') returns the text string EUR1,234,567.00.

3.96 TO_NUMBER

TO_NUMBER converts a text expression containing a number to a value of NUMBER data type.

Return Value

NUMBER

Syntax

TO_NUMBER(expr [, fmt [, 'nlsparam' ] ])

Arguments

expr is an expression to be converted to a number.

fmt is a text expression that identifies a number format model as described in the Oracle Database SQL Language Reference.

nlsparam specifies the characters used by these number format elements:

  • Decimal character

  • Group separator

  • Local currency symbol

  • International currency symbol

This argument has the format shown here:

'NLS_NUMERIC_CHARACTERS = ''dg''
 NLS_CURRENCY = ''text''
 NLS_ISO_CURRENCY = territory '

The d is the decimal character, and the g is the group separator. They must be different single-byte characters. Within the quoted string, use two single quotation marks around the parameter values. Ten characters are available for the currency symbol.

If you omit this argument or any of the NLS parameters, then this function uses the default values for your session to interpret expr.

Examples

TO_NUMBER('$1,234,567.89', 'L999G999G999D99') returns the value 1234567.89.

TO_NUMBER('EUR1,234,567.89', 'C999G999G999D99', 'NLS_ISO_CURRENCY=SPAIN') also returns the value 1234567.89.

3.97 TO_TIMESTAMP

TO_TIMESTAMP converts a text expression to a value of TIMESTAMP.

Return Value

TIMESTAMP

Syntax

TO_TIMESTAMP(char [, fmt [ 'nlsparam' ] ])

Arguments

char is a text expression to be converted.

fmt is a datetime model format specifying the format of char. The default date format is determined implicitly by the NLS_TERRITORY initialization parameter or can be set explicitly by the NLS_DATE_FORMAT parameter. For data type formats, refer to the Oracle Database SQL Language Reference.

nlsparam specifies the language in which month and day names and abbreviations given in char. This argument has this form:

'NLS_DATE_LANGUAGE = language' 

By default, char is in the session date language.

Examples

TO_TIMESTAMP('10-SEP-0614:10:10.123000','DD-MON-RRHH24:MI:SS.FF') returns the value 10-SEP-06 02.10.10.123000 PM.

TO_TIMESTAMP('10-AGOSTO-0714:10:10', 'DD-MON-RRHH24:MI:SS.FF', 'NLS_DATE_LANGUAGE=SPANISH') returns the value 10-AUG-07 02.10.10.000000 PM.

3.98 TO_TIMESTAMP_TZ

TO_TIMESTAMP_TZ converts a text expression to a value of TIMESTAMPWITHTIMEZONE data type.

Return Value

TIMESTAMP WITH TIME ZONE

Syntax

TO_TIMESTAMP_TZ(char [, fmt [ 'nlsparam' ] ])

Arguments

char is a text expression to be converted.

fmt is a datetime model format specifying the format of char. The default date format is determined implicitly by the NLS_TERRITORY initialization parameter or can be set explicitly by the NLS_DATE_FORMAT parameter. For data type formats, refer to the Oracle Database SQL Language Reference.

nlsparam specifies the language in which month and day names and abbreviations given in char. This argument has this form:

'NLS_DATE_LANGUAGE = language' 

By default, char is in the session date language.

Examples

TO_TIMESTAMP_TZ('2006-03-26 7:33:00 -4:00', 'YYYY-MM-DD HH:MI:SS TZH:TZM') returns the value 26-MAR-06 07.33.00.000000 AM -04:00.

TO_TIMESTAMP_TZ('2006-AGOSTO-13 7:33:00 -4:00', 'YYYY-MONTH-DD HH:MI:SS TZH:TZM', 'NLS_DATE_LANGUAGE=SPANISH') returns the value 13-AUG-06 07.33.00.000000 AM -04:00.

3.99 TO_YMINTERVAL

TO_YMINTERVAL converts a text expression to an INTERVAL YEAR TO MONTH data type. The function accepts argument in one of the two formats:

  • SQL interval format compatible with the SQL standard (ISO/IEC 9075:2003)

  • ISO duration format compatible with the ISO 8601:2004 standard

Return Value

INTERVAL YEAR TO MONTH

Syntax

TO_YMINTERVAL  ( ' { sql_format | ym_iso_format } ' )

sql_format::=
[+|-] years - months

ym_iso_format::=
[-] P  [ years Y  ] [months M ] [days D ] [ T  [hours H ] [minutes M ] [seconds [. frac_secs] S  ] ]

Arguments

In SQL format:

years is an integer between 0 and 999999999

months is an integer between 0 and 11.

Additional blanks are allowed between format elements.

In ISO format:

years and months are integers between 0 and 999999999.

days, hours, minutes, seconds, and frac_secs are nonnegative integers and are ignored.

No blanks are allowed in the value.

Examples

TO_YMINTERVAL('1-6') and TO_YMINTERVAL('P1Y6M') return the value +01-06 for 1 year and 6 months.

SYSDATE + TO_YMINTERVAL('1-6') adds one year and six months to the current date. When SYSDATE is 15-APR-08, the value is 15-OCT-09.

SYSDATE + TO_YMINTERVAL('P1Y6M') adds one year and six months to the current date using ISO format. When SYSDATE is 15-APR-08, the value is 15-OCT-09.

SYSDATE + TO_YMINTERVAL('-1-2') subtracts one year and two months from the current date. When SYSDATE is 15-APR-08, the value is 15-FEB-07.

3.100 TRANSLATE

TRANSLATE enables you to make several single-character, one-to-one substitutions in one operation. This expression returns an expression with all occurrences of each character in one string replaced by its corresponding character in a second string.

Return Value

CHAR | NCHAR | VARCHAR2 | NVARCHAR2

Syntax

TRANSLATE(expr, from_string, to_string)

Arguments

expr is a text expression to be modified.

from_string consists of one or more characters to be replaced in expr.

to_string consists of one or more characters that replace the corresponding characters in from_string. This string can be shorter than from_string, so that a null replaces the extra characters. However, to_string cannot be empty.

Example

TRANSLATE('disk', 'dk', 'Dc') returns the value Disc.

3.101 TRANSLATE (USING)

TRANSLATE converts a text string between the database character set and the national character set.

Note: The TRANSLATE USING function is supported primarily for ANSI compatibility. Oracle recommends that you use the TO_CHAR and TO_NCHAR functions for converting data to the database or national character sets. TO_CHAR and TO_NCHAR can take as arguments a greater variety of data types than TRANSLATE USING, which accepts only character data.

Return Value

VARCHAR2 | NVARCHAR2

Syntax

TRANSLATE (char USING { CHAR_CS | NCHAR_CS } )

Arguments

char is a text expression to be converted to the database character set (USING CHAR_CS) or the national character set (USING NCHAR_CS).

Example

TRANSLATE('north by northwest' USING NCHAR_CS) returns the value north by northwest in the national character set.

3.102 TRIM

TRIM removes leading or trailing characters (or both) from a character string.

Return Value

VARCHAR2

Syntax

TRIM([ { { LEADING | TRAILING | BOTH }[ trim_character ]  
       | trim_character
       }
       FROM 
     ]
     trim_source
    )

Arguments

LEADING removes matching characters from the beginning of the string.

TRAILING removes matching characters from the end of the string.

BOTH removes matching characters from both the beginning and the end of the string. (Default)

trim_character is a single character to be removed. By default, it is a space.

trim_source is the text expression to be trimmed.

Examples

TRIM('0' FROM '00026501.6703000') returns the value 26501.6703.

TRIM(LEADING '!' FROM '!!Help! Help!!') returns the value Help! Help!!.

3.103 TRUNC (number)

TRUNC shortens a numeric expression to a specified number of decimal places.

Return Value

NUMBER

Syntax

TRUNC(n1 [, n2 ])

Arguments

n1 is the numeric expression to be truncated.

n2 is the number of decimal places. A positive number truncates digits to the right of the decimal point, and a negative number replaces digits to the left of the decimal point. The default value is zero (0).

Examples

TRUNC(15.79) returns the value 15.

TRUNC(15.79, 1) returns the value 15.7.

TRUNC(15.79, -1) returns the value 10.

3.104 TZ_OFFSET

TZ_OFFSET returns the time zone offset from Coordinated Universal Time (UTC).

Return Value

VARCHAR2

Syntax

TZ_OFFSET({ 'time_zone_name' | '{ + | - } hh:mi'
          | SESSIONTIMEZONE | DBTMEZONE
          }
         )

Arguments

time_zone_name is the name of a time zone.

hh:mm are hours and minutes. This argument simply returns itself.

SESSIONTIMEZONE returns the session time zone.

DBTIMEZONE returns the database time zone.

Examples

TZ_OFFSET('US/Eastern') returns the offset -04:00 during Daylight Savings Time.

TZ_OFFSET('EST') returns the offset -05:00.

TZ_OFFSET(DBTIMEZONE) returns the offset -07:00 for Mountain Standard Time.

3.105 UID

UID returns a unique identifier (UID) for the session user (the user who logged on).

Return Value

INTEGER

Syntax

UID

Example

UID returns a value such as 76.

3.106 UNISTR

UNISTR converts a text string to the national character set.

Return Value

NVARCHAR2

Syntax

UNISTR ( string )

Arguments

string can be any text expression. For portability, Oracle recommends using only ASCII characters and Unicode encoding values as text literals. A Unicode encoding value has the form \xxxx where xxxx is the hexadecimal value of a character. Supplementary characters are encoded as two code units, the first from the high-surrogates range (U+D800 to U+DBFF), and the second from the low-surrogates range (U+DC00 to U+DFFF). To include a literal backslash in the string, precede it with another backslash (\\).

Example

UNISTR('abc\00e5\00f1\00f6') returns the value abcåñö.

3.107 UPPER

UPPER converts all alphabetic characters in a text expression to uppercase. The data type of the return value is the same as the original text.

Return Value

CHAR | NCHAR | VARCHAR2 | NVARCHAR2

Syntax

UPPER(char)

Arguments

char can be any text expression.

Example

UPPER('This is an emergency') returns the string THIS IS AN EMERGENCY.

3.108 USER

USER returns the name of the session user (the user who logged on).

Return Value

VARCHAR2

Syntax

USER

Example

USER returns a value such as GLOBAL.

3.109 VSIZE

VSIZE returns the number of bytes in the internal representation of an expression. It returns NULL for a null expression.

Return Value

NUMBER

Syntax

VSIZE (expr)

Arguments

expr can be an expression of any data type.

Example

VSIZE('Sound of thunder') returns the value 16.

VSIZE(CHANNEL.LONG_DESCRIPTION) returns the following values:

Channel VSIZE

Catalog

7

Direct Sales

12

Internet

8

3.110 WIDTH_BUCKET

WIDTH_BUCKET enables you to construct a histogram range divided into intervals of identical size. The function returns the bucket number into which the value of an expression falls.

When needed, WIDTH_BUCKET creates an underflow bucket numbered 0 and an overflow bucket numbered num_buckets+1. These buckets handle values outside the specified range and are helpful in checking the reasonableness of the end points.

Return Value

NUMBER

Syntax

WIDTH_BUCKET
   (expr, min_value, max_value, num_buckets)

Arguments

expr is the expression for which the histogram is being created. This expression must evaluate to a numeric or datetime value or to a value. If expr evaluates to null, then the function returns NULL.

min_value and max_value are expressions for the end points of the acceptable range for expr. Both of these expressions must evaluate to numeric or datetime values, and neither can evaluate to null.

num_buckets is an expression for the number of buckets. This expression must evaluate to a positive integer.

Example

WIDTH_BUCKET(13, 0, 20, 4) returns the value 3. It creates four buckets from 0 to 20 and sorts the value 13 into bucket 3.

WIDTH_BUCKET(-5, 0, 20, 4) returns the value 0. The value -5 is below the beginning of the range.