The following section provides a full listing and description of each vendorsupported function. These functions are vendorspecific. Thus, a MySQL function, for example, is not guaranteed to be supported by any other vendor. MySQL functions are provided to give an idea of the capabilities available within the various products. Refer to the vendor’s documentation for exact syntax usage.
Table 4.7 provides an alphabetical listing of Microsoft SQL Serversupported functions.
Table 47. Microsoft SQL ServerSupported Functions
Function 
Description 

abs(numeric_expression) 
Returns absolute value. 
acos( float_expression) 
Returns angle (in radians) whose cosine is the specified argument. 
app_name( ) 
Returns application name for current session; set by application. 
ascii(character_expression) 
Converts character to a numeric ASCII code. 
asin( float_expression) 
Returns angle (in radians) whose sine is the specified argument. 
atan( float_expression) 
Returns angle (in radians) whose tangent is the specified argument. 
atn2( float_expression, float_expressioin) 
Returns angle (in radians) whose tangent is argument1/argument1. 
avg([ All Distinct] Expression) 
Computes average of a column. 
binary_checksum(*  expression [,...n]) 
Returns binary checksum for list of expressions or row of a table. 
cast(Expression as Data Type) 
Converts a valid SQL Server expression to the specified datatype. 
ceiling(numeric_expression) 
Returns smallest integer greater than or equal to the argument. 
char(integer_expression) 
Converts a numeric ASCII code to a character. 
charindex(expression1, expression2 [, start_location]) 
Returns position of the first occurrence of a substring in a string. 
checksum(*  expression [,...n]) 
Returns checksum value (computed over row values or expressions provided). 
checksum_agg([ALL  Distinct] expression) 
Returns checksum of the values in group. 
coalesce(expression [,...n]) 
Returns the first nonNULL argument from a list of arguments. 
col_length(`table', `column') 
Returns column length in bytes. 
col_name(table_id, column_id) 
Returns column name, given table ID and column ID. 
contains({column  }, `contains_search_condition'}) 
Searches columns on exact or “fuzzy” matches of contains_seach_criteria. It is an elaborate function used to perform fulltext searches. Refer to the vendor documentation for more information. 
containsable(table, column, contains_search_condition) 
Returns a table with exact and “fuzzy” matches of contains_search_condition. It is an elaborate function used to perform fulltext searches. Refer to the vendor documentation for more information. 
convert(data_type [(length)], expression [, style]) 
Converts data from one datatype to another. 
cos(float_expression) 
Returns cosine. 
cot(float_expression) 
Returns cotangent. 
count({[All  Distinct] expression] *}) 
Counts rows. 
count(*) 
Computes the number of rows, including those with NULL values. 
count( DISTINCT expression ) 
Calculates the number of distinct nonNULL values in a column or expression. Each group of rows with the same value of expressionadds 1 to the result. 
count( expression ) 
Returns the number of rows with nonNULL values in a certain column or expression. 
count_big([All  Distinct] expression) 
Same as count except returns big integer. 
current_timestamp 
Returns current date and time. 
current_user 
Returns username in the current database of the current session. 
datalength(expression) 
Returns number of bytes in a character or binary string. 
databasepropertyex(database, property) 
Returns database option or property. 
dateadd(datepart, number, date) 
Adds a number of dateparts (e.g., days) to a datetime value. 
datediff(datepart, startdate, enddate) 
Calculates difference between two datetime values expressed in certain dateparts. 
datename(datepart, date) 
Returns name of a datepart (e.g., month) of a datetime argument. 
datepart(datepart, date) 
Returns value of a datepart (e.g., hour) of a datetime argument. 
day(date) 
Returns an integer value representing the day of the date provided as a parameter. 
db_id(`[database_name]') 
Returns database ID and given name. 
db_name(database_id) 
Returns the database name. 
degrees(numeric_expression) 
Converts radians to degrees. 
difference(character_expression, character_expression) 
Compares how two arguments sound and returns a number from 0 to 4. Higher result indicates better phonetic match. 
exp(float_expression) 
Returns exponential value. 
floor(numeric_expression) 
Returns largest integer less than or equal to the argument. 
file_id(`file_name') 
Returns the file ID for the logical filename. 
file_name(file_id) 
Returns the logical filename for file ID. 
filegroup_id(`filegroup_name') 
Returns filegroup ID for the logical filegroup name. 
filegroup_name(filegroup_id) 
Returns the logical filegroup name for filegroup ID. 
filegroupproperty(filegroup_name, property) 
Returns filegroup property value for the specified property. 
fileproperty(file, property) 
Returns file property value for the specified property. 
fulltextcatalogproperty(catalog_name, property) 
Returns fulltext catalog properties. 
fulltextserviceproperty(property) 
Returns fulltext service level properties. 
formatmessage(msg_number, param_value [,... n ]) 
Constructs a message from an existing message in SYSMESSAGES table (similar to RAISERROR). 
freetexttable(table { column *}, `freetext_string’ [, top_n_by_rank]) 
Used for fulltext search; returns a table with columns that match the meaning but don’t exactly match value of freetext_string. 
getdate( ) 
Returns current date and time. 
getansinull([`database']) 
Returns default nullability setting for new columns. 
getutcdate( ) 
Returns Universal Time Coordinate (UTC) date. 
grouping(column_name) 
Returns 1 when the row is added by CUBE or ROLLUP; otherwise, returns 0. 
host_id( ) 
Returns workstation ID of a given process. 
host_name( ) 
Returns process hostname. 
ident_incr(`table_or_view') 
Returns identitycolumn increment value. 
ident_seed(`table_or_view') 
Returns identity seed value. 
ident_current(`table_name') 
Returns the last identity value generated for the specified table. 
identity(data_type [, seed, increment]) As column_name 
Used in SELECT INTO statement to insert an identity column into the destination table. 
index_col(`table', index_id, key_id) 
Returns index column name, given table ID, index ID, and column sequential number in the index key. 
indexproperty(table_id, index, property) 
Returns index property (such as Fillfactor). 
isdate(expression) 
Validates if a character string can be converted to DATETIME. 
is_member({`group’  `role'}) 
Returns true or false (1 or 0) depending on whether user is a member of NT group or SQL Server role. 
is_srvrolemember(`role’ [,'login']) 
Returns true or false (1 or 0) depending on whether user is a member of specified server role. 
isnull(check_expression, replacement_value) 
Returns the first argument if it is not NULL; otherwise, returns the second argument. 
isnumeric(expression) 
Validates if a character string can be converted to NUMERIC. 
left(character_expression, integer_expression) 
Returns a portion of a character expression, starting at integer_expression from left. 
len(string_expression) 
Returns the number of characters in the expression. 
log(float_expression) 
Returns natural logarithm. 
log10(float_expression) 
Returns base10 logarithm. 
lower(character_expression) 
Converts a string to lowercase. 
ltrim(character_expression) 
Trims leadingspace characters. 
max([All  Distinct] expression) 
Finds maximum value in a column. 
min([All  Distinct] expression) 
Finds minimum value in a column. 
month(date) 
Returns month part of the date provided. 
nchar(integer_expression) 
Returns the unicode character with the given integer code. 
newid( ) 
Creates a new unique identifier of type uniqueidentifier. 
nullif(expression, expression) 
Returns NULL if two specified expressions are equivalent. 
object_id(`object') 
Returns object ID and given name. 
object_name(object_id) 
Returns object name and given ID. 
objectproperty(id, property) 
Table 4.8 provides an alphabetical listing of MySQLsupported functions.
Table 48. MySQLSupported Functions
Table 4.9 provides an alphabetical listing of the SQL functions specific to Oracle.
Table 49. OracleSupported Functions
Function 
Description 

abs(number) 
Returns the absolute value of number. 
acos(number) 
Returns the arc cosine of number ranging from 1 to 1. The result ranges from 0 to π and is expressed in radians. 
add_months(date, int) 
Returns the date dateplus int months. 
ascii(string) 
Returns the decimal value in the database character set of the first character of string; returns an ASCII value when the database character set is 7bit ASCII; returns EBCDIC values if the database character set is EBCDIC Code Page 500. 
asin(number) 
Returns the arc sine of number ranging from 1 to 1. The resulting value ranges from π/2 to π/2 and is expressed in radians. 
atan(number) 
Returns the arctangent of any number. The resulting value ranges from π/2 to π/2 and is expressed in radians. 
atan2(number,nbr) 
Returns the arctangent of number and nbr. The values for number and nbr are not restricted, but the results range from π to π and are expressed in radians. 
avg([DISTINCT ] expression) over (analytics) 
Returns the average value of expr. It can be used as an aggregate or analytic function (analytic functions are beyond the scope of this text). 
bfilename(`directory','filename') 
Returns a BFILE locator associated with a physical LOB binary filename on the server’s filesystem in directory. 
ceil(number) 
Returns smallest integer greater than or equal to number. 
chartorowid(char) 
Converts a value from a character datatype (CHAR or VARCHAR2 datatype) to ROWID datatype. 
chr(number [USING NCHAR_CS]) 
Returns the character having the binary equivalent to number in either the database character set (if USING NCHAR_CS is not included) or the national character set (if USING NCHAR_CS is included). 
concat(string1, string2) 
Returns string1 concatenated with string2. It is equivalent to the concatenation operator (). 
convert(char_value, target_char_set, source_char_set) 
Converts a character string from one character set to another; returns the char_value in the target_char_set after converting char_value from the source_char_set. 
corr(expression1, expression2) over (analytics) 
Returns the correlation coefficient of a set of numbered pairs (expressions 1 and 2). It can be used as an aggregate or analytic function (analytic functions are beyond the scope of this text). 
cos(number) 
Returns the cosine of number as an angle expressed in radians. 
cosh(number) 
Returns the hyperbolic cosine of number. 
count 
Returns the number of rows in the query; refer to the earlier section on COUNT for more information. 
covar_pop(expression1, expression2) over(analytics) 
Returns the population covariance of a set of number pairs (expressions 1 and 2). It can be used as an aggregate or analytic function (analytic functions are beyond the scope of this text). 
covar_samp(expression1, expression2) over(analytics) 
Returns the sample covariance of a set of number pairs (expressions 1 and 2). It can be used as an aggregate or analytic function (analytic functions are beyond the scope of this text). 
cume_dist( ) ( [OVER (query)] ORDER BY...) 
The cumulative distribution function computes the relative position of a specified value in a group of values. 
decode(expr search, result [,. n] [,default]) 
Compares expr to the search value; if expr is equal to a search, returns the result. Without a match, DECODE returns default, or NULL if default is omitted. Refer to Oracle documentation for more details. 
dense_rank( ) ( [OVER (query)] ORDER BY...) 
Computes the rank of each row returned from a query with respect to the other rows, based on the values of the value_exprs in the ORDER_BY_clause. 
deref(expression) 
Returns the object reference of expression, where expression must return a REF to an object. 
dump(expression [,return_ format [, starting_at [,length]]] ) 
Returns a VARCHAR2 value containing a datatype code, length in bytes, and internal representation of expression. The resulting value is returned in the format of return_ format. 
empth[B  C]lob( ) 
Returns an empty LOB locator that can be used to initialize a LOB variable. It can also be used to initialize a LOB column or attribute to empty in an INSERT or UPDATE statement. 
exp(number) 
Returns E raised to the number ed power, where E = 2.71828183. 
first_value( expression) over (analytics) 
Returns the first value in an ordered set of values. 
floor(number) 
Returns largest integer equal to or less than number. 
greatest(expression [,...n]) 
Returns the greatest of the list of expressions. All expressions after the first are implicitly converted to the datatype of the first expression before the comparison. 
grouping(expression) 
Distinguishes null cause by a superaggregation in GROUP BY extension from an actual null value. 
hextoraw(string) 
Converts string containing hexadecimal digits into a raw value. 
initcap(string) 
Returns string, with the first letter of each word in uppercase and all other letters in lowercase. 
instr(string1, string2, start_at, occurrence) 
Searches one character string for another character string. INSRT search char1 with a starting position of start_at (an integer) looking for the numeric occurrence within string2. Returns the position of the character in string1 that is the first character of this occurrence. 
instrb(string1, string2, [start_a[t, occurrence]]) 
The same as INSTR, except that start_at and the return value are expressed in bytes instead of characters. 
lag(expression [,offset][,default]) over(analytics) 
Provides access to more than one row of a table at the same time without a self join; refer to the vendor documentation for more information. 
last_day(date) 
Returns the date of the last day of the month that contains date. 
last_value(expression) over (analytics) 
Returns the last value in an ordered set of values; refer to the vendor documentation for more information. 
lead(expression [,offset][,default]) over(analytics) 
Provides access to more than one row of a table at the same time without a self join. Analytic functions are beyond the scope of this text. 
least(expression [,...n]) 
Returns the least of the list of expressions. 
length(string) 
Returns the integer length of string, or null if string is null. 
lengthb(string) 
Returns the length of char in bytes; otherwise, the same as LENGTH. 
ln(number) 
Returns the natural logarithm of number, where the number is greater than 0. 
log(base_number, number) 
Returns the logarithm of any base_number of number. 
lower(string) 
Returns string in the same datatype as it was supplied with all characters lowercase. 
lpad(string1, number [,string2]) 
Returns string1, leftpadded to length number using characters in string2; string2 defaults to a single blank. 
ltrim(string[, set]) 
Removes all characters in set from the left of string. Set defaults to a single blank. 
make_ref({table_name  view_name}, key [,...n]) 
Creates a reference (REF ) to a row of an object view or a row in an object table whose object identifier is primary keybased. 
max([DISTINCT] expression) over (analytics) 
Returns maximum value of expression. It can be used as an aggregate or analytic function (analytic functions are beyond the scope of this text). 
min([DISTINCT] expression) over (analytics) 
Returns minimum value of expression. It can be used as an aggregate or analytic function (analytic functions are beyond the scope of this text). 
mod(dividend, divider) 
Returns remainder of dividend divided by divider ; returns the dividend if divider is 0. 
months_between(date1, date2) 
Returns number of months between dates date1 and date2. When date1 is later than date2, the result is positive. If it is earlier, the result is negative. 
new_time(date, time_zone1, time_zone2) 
Returns the date and time in time_zone2 when date and time in time_zone1 are date. Time_zones 1 and 2 may be any of these text strings:

next_day(date, string) 
Returns the date of the first weekday named by string that is later than date. The argument string must be either the full name or the abbreviation of a day of the week in the date language of the session. 
nls_charset_decl_len(bytecnt, csid) 
Returns the declaration width (bytecnt) of an NCHAR column using the character set ID (csid ) of the column. 
nls_charset_id(text) 
Returns the NLS character set ID number corresponding to text. 
nls_charset_name(number) 
Returns the VARCHAR2 name for the NLS character set corresponding to the ID number. 
nls_initcap(string [,'nlsparameter']) 
Returns string with the first letter of each word in uppercase and all other letters in lowercase. The nlsparameter offers special linguistic sorting features. 
nls_lower(string, [,'nlsparameter']) 
Returns string with all letters lowercase. The nlsparameter offers special linguistic sorting features. 
nlssort(string [,'nlsparameter']) 
Returns the string of bytes used to sort string. The nlsparameter offers special linguistic sorting features. 
nls_upper string [,'nlsparameter']) 
Returns string with all letters uppercase. The nlsparameter offers special linguistic sorting features. 
ntile(expression) over ( query_partition ORDER BY...) 
Divides an ordered data set into a number of buckets numbered 1 to expression and assigns the appropriate bucket number to each row. 
numtodsinterval(number, `string') 
Converts number to an INTERVAL DAY TO SECOND literal, where number is a number or an expression resolving to a number, such as a numeric datatype column. 
numtoyminterval(number, `string') 
Converts number to an INTERVAL DAY TO MONTH literal, where number is a number or an expression resolving to a number, such as a numeric datatype column. 
nvl(expression1, expression2) 
If expression1 is null, expression2 is returned in the place of a null value. Otherwise, expression1 is returned. The expressions may be any datatype. 
nvl2(expression1, expression2, expression3) 
Similar to NLV, except that if expression1 is not null, expression2 is returned. If expression1 is null, expression3 is returned. The expressions may be any datatype, except LONG. 
percent_rank( ) over ( query_partition ORDER BY...) 
Similar to the CUME_DIST analytical function. Rather than return the cumulative distribution, it returns the percentage rank of a row compared to the others in its result set. Refer to the vendor documentation for more assistance. 
power(number, power) 
Returns number raised to the nth power. The base and the exponent can be any numbers, but if number is negative, power must be an integer. 
rank (value_expression) over ( query_partition ORDER BY ...) 
Computes the rank of each row returned from a query with respect to the other rows returned by the query, based on the values of the value_expression in the ORDER_BY_clause. 
ratio_to_report (value_exprs) over ( query_partition) 
Computes the ratio of a value to the sum of a set of values. If values_expr is null, the ratiotoreport value also is null. 
rawtohex(raw) 
Converts a raw value to a string (character datatype) of its hexadecimal equivalent. 
ref(table_alias) 
REF takes a table alias associated with a row from a table or view. A special reference value is returned for the object instance that is bound to the variable or row. 
reftohex(expression) 
Converts argument expression to a character value containing its hexadecimal equivalent. 
regr_ xxx(expression1, expression2) over (analytics) 
Linear regression functions fit an ordinaryleastsquares regression line to a set of number pairs where expression1 is the dependent variable and expression2 is the independent variable. The linear regression functions are:
These can be used as aggregate or analytic functions. 
replace(string, search_string [,replacement_string]) 
Returns string with every occurrence of search_string replaced with replacement_string. 
round (number, decimal) 
Returns number rounded to decimal places right of the decimal point. When decimal is omitted, number is rounded to places. Note that decimal, an integer, can be negative to round off digits left of the decimal point. 
round (date[, format]) 
Returns the date rounded to the unit specified by the format model format. When format is omitted, date is rounded to the nearest day. 
row_number ( ) over ( query_partition ORDER BY ... ) 
Assigns a unique number to each row where it is applied in the ordered sequence of rows specified by the ORDER_BY_clause, beginning with 1. 
rowidtochar(rowid) 
Converts a rowid value to VARCHAR2 datatype, 18 characters long. 
rpad(string1, number [, string2]) 
Returns string1, rightpadded to length number with the value of string2, repeated as needed. String2 defaults to a single blank. 
rtrim(string[,set]) 
Returns string, with all the rightmost characters that appear in set removed; set defaults to a single blank. 
sign(number) 
When number < 0, returns 1. When number = 0, returns 0. When number > 0, returns 1. 
sin(number) 
Returns the sine of number as an angle expressed in radians. 
sinh(number) 
Returns the hyperbolic sine of number. 
soundex(string) 
Returns a character string containing the phonetic representation of string. This function allows words that are spelled differently but sound alike in English to be compared for equality. 
sqrt(number) 
Returns square root of number, a nonnegative number. 
stddev( [DISTINCT] expression) over (analytics) 
Returns sample standard deviation of a set of numbers shown as expression. 
stdev_pop(expression) over (analytics) 
Computes the population standard deviation and returns the square root of the population variance. 
seddev_samp(expression) over (analytics) 
Computes the cumulative sample standard deviation and returns the square root of the sample variance. 
substr(extraction_string [FROM starting_position] [FOR length]) 
Refer to the earlier section on SUBSTR. 
substrb(extraction_string [FROM starting_position] [FOR length]) 
SUBSTRB is the same as SUBSTR, except that the arguments m starting_position and length are expressed in bytes, rather than in characters. 
sum([DISTINCT ] expression) over (analytics) 
Returns sum of values of expr ; refer to vendor documentation for assistance with analytics and the OVER subclause. 
sys_context(`namespace','attribute'[,length]) 
Returns the value of attribute associated with the context namespace, usable in both SQL and PL/SQL statements. 
sys_guid( ) 
Generates and returns a globally unique identifier

sysdate 
Returns the current date and time, requiring no arguments. 
tan(number) 
Returns the tangent of number as an angle expressed in radians. 
tanh(number) 
Returns the hyperbolic tangent of number 
to_char (date [, format [, `nls_parameter']]) 
Converts date to a VARCHAR2 in the format specified by the date format format. When fmt is omitted, date is converted to the default date format. The nls_parameter option offers additional control over formatting options. 
to_char (number [, format [, `nls_parameter']]) 
Converts number to a VARCHAR2 in the format specified by the number format format. When fmt is omitted, number is converted to a string long enough to hold the number. The nls_parameter option offers additional control over formatting options. 
to_date(string [, format [, `nls_parameter']]) 
Converts string (in CHAR or VARCHAR2) to a DATE datatype. The nls_parameter option offers additional control over formatting options. 
to_lob(long_column) 
Usable only by LONG or LONG RAW expressions, it converts LONG or LONG RAW values in the column long_column to LOB values. It is usable only in the SELECT list of a subquery in an INSERT statement. 
to_multi_byte(string) 
Returns string with all of its singlebyte characters converted to their corresponding multibyte characters. 
to_number(string [, format [,'nls_parameter']]) 
Converts a numeric string (of CHAR or VARCHAR2 datatype) to a value of a NUMBER datatype in the format specified by the optional format model format. The nls_parameter option offers additional control over formatting options. 
to_single_byte(string) 
Returns string with all of its multibyte characters converted to their corresponding singlebyte characters. 
translate(`char_value', `from_text', `to_text') 
Returns char_value with all occurrences of each character in from_text replaced by its corresponding character in to_text; refer to CONVERT and TRANSLATE earlier in this chapter for more information on TRANSLATE. 
translate (text USING [CHAR_CS  NCHAR_CS] ) 
Converts text into the character set specified for conversions between the database character set or the national character set. 
trim({[LEADING  TRAILING  BOTH] trim_char  trim_char } FROM trim_source} ) 
Enables leading or trailing characters (or both) to be trimmed from a character string. 
trunc (base [, number]) 
Returns base truncated to number decimal places. When number is omitted, base is truncated to places. Number can be negative to truncate (make zero) number digits left of the decimal point. 
trunc (date [, format]) 
Returns date with any time data truncated to the unit specified by format. When format is omitted, date is truncated to the nearest whole day. 
uid 
Returns an integer that uniquely identifies the session user who logged on. No parameters are needed. 
upper(string) 
Returns string with all letters in uppercase. 
user 
Returns the name of the session user who logged on in VARCHAR2. 
userenv(option) 
Returns information about the current session in VARCHAR2. 
value(table_alias) 
Takes as a table alias associated with a row in an object table and returns object instances stored within the object table. 
var_pop(expression) over (analytics) 
Returns the population variance of a set of numbers after discarding the nulls in the expression number set. Analytic functions are covered in the vendor documentation. 
var_samp(expression) over (analytics) 
Returns the sample variance of a set of numbers after discarding the nulls in the expression number set. Analytic functions are covered in the vendor documentation. 
variance([DISTINCT] expression) over (analytics) 
Returns variance of expression calculated as follows:

vsize(expression) 
Returns the number of bytes in the internal representation of expression. When expression is null, it returns null. 
Table 4.10 lists the functions specific to PostgreSQL.
Table 410. PostgreSQLSupported Functions
Function 
Description 

abstime(timestamp) 
Converts to abstime 
abs(float8) 
Returns absolute value 
acos(float8) 
Returns arccosine 
age(timestamp) 
Preserves months and years 
age(timestamp, timestamp) 
Preserves months and years 
area(object) 
Returns area of item 
asin(float8) 
Returns arcsine 
atan(float8) 
Returns arctangent 
atan2(float8,float8) 
Returns arctangent 
box(box,box) 
Returns intersection box 
box(circle) 
Converts circle to box 
box(point,point) 
Returns points to box 
box(polygon) 
Converts polygon to box 
broadcast(cidr) 
Constructs broadcast address as text 
broadcast(inet) 
Constructs broadcast address as text 
CASE WHEN expr THEN expr [...] ELSE expr END 
Returns expression for first true WHEN clause 
cbrt(float8) 
Returns cube root 
center(object) 
Returns center of item 
char(text) 
Converts text to char type 
char(varchar) 
Converts varchar to char type 
char_length(string) 
Returns length of string 
character_length(string) 
Returns length of string 
circle(box) 
Converts to circle 
circle(point,float8) 
Converts point to circle 
COALESCE(list) 
Returns first nonNULL value in list 
cos(float8) 
Returns cosine 
cot(float8) 
Returns cotangent 
date_part(text,timestamp) 
Returns portion of date 
date_part(text,interval) 
Returns portion of time 
date_trunc(text,timestamp) 
Truncates date 
degrees (float8) 
Converts radians to degrees 
diameter(circle) 
Returns diameter of circle 
exp(float8) 
Raises e to the specified exponent 
float(int) 
Converts integer to floating point 
float4(int) 
Converts integer to floating point 
height(box) 
Returns vertical size of box 
host(inet) 
Extracts host address as text 
initcap(text) 
Converts first letter of each word to uppercase 
interval(reltime) 
Converts to interval 
integer(float) 
Converts floating point to integer 
isclosed(path) 
Returns a closed path 
isopen(path) 
Returns an open path 
isfinite(timestamp) 
Returns a finite time 
isfinite(interval) 
Returns a finite time 
length(object) 
Returns length of item 
ln(float8) 
Returns natural logarithm 
log(float8) 
Returns base10 logarithm 
lower(string) 
Converts string to lowercase 
lseg(box) 
Converts box diagonal to lseg 
lseg(point,point) 
Converts points to lseg 
lpad(text,int,text) 
Returns leftpad string to specified length 
ltrim(text,text) 
Returns lefttrim characters from text 
masklen(cidr) 
Calculates netmask length 
masklen(inet) 
Calculates netmask length 
netmask(inet) 
Constructs netmask as text 
npoint(path) 
Returns number of points 
NULLIF(input,value) 
Returns NULL if input = value, else returns input 
octet_length(string) 
Returns storage length of string 
path(polygon) 
Converts polygon to path 
pclose(path) 
Converts path to closed 
pi( ) 
Returns fundamental constant 
polygon(box) 
Returns 12point polygon 
polygon(circle) 
Returns 12point polygon 
polygon(npts,circle) 
Returns npts polygon 
polygon(path) 
Converts path to polygon 
point(circle) 
Returns center 
point(lseg,lseg) 
Returns intersection 
point(polygon) 
Returns center 
position(string in string) 
Returns location of specified substring 
pow (float8,float8) 
Raises a number to the specified exponent 
popen(path) 
Converts path to open path 
reltime(interval) 
Converts to reltime 
radians(float8) 
Converts degrees to radians 
radius(circle) 
Returns radius of circle 
round(float8) 
Rounds to nearest integer 
rpad(text,int,text) 
Converts right pad string to specified length 
rtrim(text,text) 
Converts right trim characters from text 
sin(float8) 
Returns sine 
sqrt(float8) 
Returns square root 
substring(string [from int] [for int]) 
Extracts specified substring 
substr(text,int[,int]) 
Extracts specified substring 
tan(float8) 
Returns tangent 
text(char) 
Converts char to text type 
text(varchar) 
Converts varchar to text type 
textpos(text,text) 
Locates specified substring 
timestamp(date) 
Converts to timestamp 
timestamp(date,time) 
Converts to timestamp 
to_char(timestamp, text) 
Converts timestamp to string 
to_char(int, text) 
Converts int4/int8 to string 
to_char(float, text) 
Converts float4/float8 to string 
to_char(numeric, text) 
Converts numeric to string 
to_date(text, text) 
Converts string to date 
to_number(text, text) 
Converts string to numeric 
to_timestamp(text, text) 
Converts string to timestamp 
translate(text,from,to) 
Converts character in string 
trim([leadingtrailingboth] [string] from string) 
Trims characters from string 
trunc(float8) 
Truncates (towards zero) 
upper(text) 
Converts text to uppercase 
varchar(char) 
Converts char to varchar type 
varchar(text) 
Converts text to varchar type 
width(box) 
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