SPARQL Functions Reference¶

What’s in this document?

SPARQL functions vs magic predicates
SPARQL 1.1 functions
SPARQL 1.1 constructor functions
Mathematical function extensions
Date and time function extensions
SPARQL SPIN functions
RDF-star extension functions
RDF list function extensions
Aggregation function extensions
GeoSPARQL functions
- GeoSPARQL extension functions
Geospatial extension functions
Other function extensions

This section lists all supported SPARQL functions in GraphDB. The function specifications include the types of the arguments and the output. Types from XML Schema should be readily recognizable as they start with the xsd: prefix. In addition, the following more generic types are used:

rdfTerm: Any RDF value: a literal, a blank node or an IRI.
iri: An IRI.
bnode: A blank node.
literal: A literal regardless of its datatype or the presence of a language tag.
string: A plain literal or a literal with a language tag. Note that plain literals have the implicit datatype xsd:string.
numeric: A literal with a numeric XSD datatype, e.g. xsd:double and xsd:long.
variable: A SPARQL variable.
expression: A SPARQL expression that may use any constants and variables to compute a value.

SPARQL functions vs magic predicates ¶

Functions and magic predicates are denoted and used differently. Magic predicates are similar to how GraphDB plugins can interpret certain triple patterns, and unlike functions, they can return multiple values per call.

Functions are denoted like this: ex:function(arg1, arg2, ...) where all arguments must be bound, and are used in bind, in select expressions, in the order clause, etc.
Magic predicates are denoted like this: subject ex:magicPredicate (arg1 arg2 ...) where in some cases, the arguments are allowed to be unbound (and are then calculated from the subject). They are used as triple patterns. The object is an RDF list of the arguments (indicated by the parentheses on the right-hand side).

SPARQL 1.1 functions ¶

Function	Description
`xsd:boolean BOUND(variable var)`	Returns `true` if the variable var is bound to a value. Returns `false` otherwise. Variables with the value NaN or INF are considered bound. More
`rdfTerm IF(expression e1, expression e2, expression e3)`	The IF function form evaluates the first argument, interprets it as a effective boolean value, then returns the value of e2 if the EBV is true, otherwise it returns the value of e3. Only one of e2 and e3 is evaluated. If evaluating the first argument raises an error, then an error is raised for the evaluation of the IF expression. More
`rdfTerm COALESCE(expression e1, …)`	The COALESCE function form returns the RDF term value of the first expression that evaluates without error. In SPARQL, evaluating an unbound variable raises an error. If none of the arguments evaluates to an RDF term, an error is raised. If no expressions are evaluated without error, an error is raised. More
`xsd:boolean NOT EXISTS { pattern }` `xsd:boolean EXISTS { pattern }`	There is a filter operator EXISTS that takes a graph pattern. EXISTS returns `true` or `false` depending on whether the pattern matches the dataset given the bindings in the current group graph pattern, the dataset and the active graph at this point in the query evaluation. No additional binding of variables occurs. The NOT EXISTS form translates into `fn:not(EXISTS{...})`. More
`xsd:boolean xsd:boolean left \|\| xsd:boolean right`	Returns a logical OR of left and right. Note that logical-or operates on the effective boolean value of its arguments. More
`xsd:boolean xsd:boolean left && xsd:boolean right`	Returns a logical AND of left and right. Note that logical-and operates on the effective boolean value of its arguments. More
`xsd:boolean rdfTerm term1 = rdfTerm term2`	Returns `true` if term1 and term2 are equal. Returns `false` otherwise. IRIs and blank nodes are equal if they are the same RDF term as defined in RDF Concepts. Literals are equal if they have an XSD datatype, the same language tag (if any) and their values produced by applying the lexical-to-value mapping of their datatypes are also equal. If the arguments are both literal but their datatype is not an XSD datatype an error will be produced. More
`xsd:boolean sameTerm(rdfTerm term1, rdfTerm term2)`	Returns `true` if term1 and term2 are the same RDF term as defined in RDF Concepts; returns `false` otherwise. More
`xsd:boolean rdfTerm term IN (expression e1, …)`	The IN operator tests whether the RDF term on the left-hand side is found in the values of list of expressions on the right-hand side. The test is done with `=` operator, which compares the RDF term to each expression for equality. More
`xsd:boolean rdfTerm term NOT IN (expression e1, …)`	The NOT IN operator tests whether the RDF term on the left-hand side is not found in the values of list of expressions on the right-hand side. The test is done with `!=` operator, which compares the RDF term to each expression for inequality. More
`xsd:boolean isIRI(rdfTerm term)` `xsd:boolean isURI(rdfTerm term)`	Returns `true` if term is an IRI. Returns `false` otherwise. More
`xsd:boolean isBlank(rdfTerm term)`	Returns `true` if term is a blank node. Returns `false` otherwise. More
`xsd:boolean isLiteral(rdfTerm term)`	Returns `true` if term is a literal. Returns `false` otherwise. More
`xsd:boolean isNumeric(rdfTerm term)`	Returns `true` if term is a numeric value. Returns `false` otherwise. A term is numeric if it has an appropriate datatype and has a valid lexical form, making it a valid argument to functions and operators taking numeric arguments. More
`xsd:string STR(literal ltrl)` `xsd:string STR(iri rsrc)`	Returns the lexical form of ltrl (a literal); returns the codepoint representation of rsrc (an IRI). This is useful for examining parts of an IRI, for instance, the hostname. More
`xsd:string LANG(literal ltrl)`	Returns the language tag of the literal ltrl, if it has one. It returns “” if ltrl has no language tag. Note that the RDF data model does not include literals with an empty language tag. More
`iri DATATYPE(literal ltrl)`	Returns the datatype IRI of the literal ltrl. More
`iri IRI(string str)` `iri IRI(iri rsrc)` `iri URI(string str)` `iri URI(iri rsrc)`	The IRI function constructs an IRI by resolving the string argument str. The IRI is resolved against the base IRI of the query and must result in an absolute IRI. If the function is passed an IRI rsrc, it returns the IRI unchanged. More
`bnode BNODE()` `bnode BNODE(string str)`	The BNODE function constructs a blank node that is distinct from all blank nodes in the dataset being queried and distinct from all blank nodes created by calls to this constructor for other query solutions. If the no argument form is used, every call results in a distinct blank node. If the form with the string str is used, every call results in distinct blank nodes for different strings, and the same blank node for calls with the same string within expressions for one solution mapping. More
`iri UUID()`	Return a fresh IRI from the UUID URN scheme. Each call of UUID() returns a different UUID. More
`xsd:string STRUUID()`	Return a string that is the scheme specific part of UUID. That is, as a string literal, the result of generating a UUID, converting to a string literal and removing the initial `urn:uuid:`. More
`xsd:integer STRLEN(string str)`	The STRLEN function corresponds to the XPath `fn:string-length` function and returns an `xsd:integer` equal to the length in characters of the lexical form of the string str. More
`string SUBSTR(string source, xsd:integer startingLoc)` `string SUBSTR(string source, xsd:integer startingLoc, xsd:integer length)`	The SUBSTR function corresponds to the XPath `fn:substring` function and returns a literal of the same kind (string literal or literal with language tag) as the source input parameter but with a lexical form formed from the substring of the lexical form of the source. More
`string UCASE(string str)`	The UCASE function corresponds to the XPath `fn:upper-case` function. It returns a string literal whose lexical form is the upper case of the lexical form of the argument. More
`string LCASE(string str)`	The LCASE function corresponds to the XPath `fn:lower-case` function. It returns a string literal whose lexical form is the lower case of the lexical form of the argument. More
`xsd:boolean STRSTARTS(string str1, string str2)`	The STRSTARTS function corresponds to the XPath `fn:starts-with` function and returns `true` if the lexical form of str1 starts with the lexical form of str2, otherwise it returns `false`. More
`xsd:boolean STRENDS(string str1, string str2)`	The STRENDS function corresponds to the XPath `fn:ends-with` function and returns `true` if the lexical form of str1 ends with the lexical form of str2, otherwise it returns `false`. More
`xsd:boolean CONTAINS(string str1, string str2)`	The CONTAINS function corresponds to the XPath `fn:contains` function and returns `true` if the lexical form of str1 contains the lexical form of str2 as a substring. More
`string STRBEFORE(string str1, string str2)`	The STRBEFORE function corresponds to the XPath `fn:substring-before` function and returns a literal of the same kind as str1. The lexical form of the result is the substring of the lexical form of str1 that precedes the first occurrence of the lexical form of str2. If the lexical form of str2 is the empty string, this is considered to be a match and the lexical form of the result is the empty string. If there is no such occurrence, an empty string literal is returned. More
`string STRAFTER(string str1, string str2)`	The STRAFTER function corresponds to the XPath `fn:substring-after` function and returns a literal of the same kind as str1. The lexical form of the result is the substring of the lexical form of str1 that follows the first occurrence of the lexical form of str2. If the lexical form of str2 is the empty string, this is considered to be a match and the lexical form of the result is the empty string. If there is no such occurrence, an empty simple literal is returned. More
`xsd:string ENCODE_FOR_URI(string str)`	The ENCODE_FOR_URI function corresponds to the XPath `fn:encode-for-uri` function. It returns a simple literal with the lexical form obtained from the lexical form of its input after translating reserved characters according to the `fn:encode-for-uri` function. More
`string CONCAT(string str1, …)`	The CONCAT function corresponds to the XPath `fn:concat` function. The function accepts string literals as arguments. The lexical form of the returned literal is obtained by concatenating the lexical forms of its inputs. If all input literals are literals with identical language tag, then the returned literal is a literal with the same language tag, in all other cases, the returned literal is a simple literal. More
`xsd:boolean langMatches(xsd:string languageTag, xsd:string languageRange)`	Returns `true` if languageTag (first argument) matches languageRange (second argument). According to language tag semantics, the matching is case-insensitive. languageRange is a basic language range. For example, “en” will match any of the languageTags “en”, “EN”, “En”, “en-GB”, “en-US”, etc. A language range of “*” matches any non-empty language tag string. More
`xsd:boolean REGEX(string text, xsd:string pattern)` `xsd:boolean REGEX(string text, xsd:string pattern, xsd:string flags)`	Invokes the XPath `fn:matches` function to match text against a regular expression pattern. Regular expression matching may involve the modifier `flags`: “i” requests case-insensitive matching. More
`string REPLACE(string arg, xsd:string pattern, xsd:string replacement)` `string REPLACE(string arg, xsd:string pattern, xsd:string replacement, xsd:string flags)`	The `REPLACE` function corresponds to the XPath `fn:replace` function. It replaces each non-overlapping occurrence of the regular expression pattern with the replacement string. Regular expression matching may involve the modifier `flags`: “i” requests case-insensitive matching. More
`numeric ABS(numeric num)`	Returns the absolute value of num. An error is raised if the argument is not a numeric value. This function is the same as `fn:numeric-abs` for terms with a datatype from XDM. More
`numeric ROUND(numeric num)`	Returns the number with no fractional part that is closest to num. If there are two such numbers, then the one that is closest to positive infinity is returned. An error is raised if the argument is not a numeric value. This function is the same as `fn:numeric-round` for terms with a datatype from XDM. More
`numeric CEIL(numeric num)`	Returns the smallest (closest to negative infinity) number with no fractional part that is not less than the value of num. An error is raised if the argument is not a numeric value. This function is the same as `fn:numeric-ceil` for terms with a datatype from XDM. More
`numeric FLOOR(numeric num)`	Returns the largest (closest to positive infinity) number with no fractional part that is not greater than the value of num. An error is raised if the argument is not a numeric value. This function is the same as `fn:numeric-floor` for terms with a datatype from XDM. More
`xsd:double RAND()`	Returns a pseudo-random number between 0 (inclusive) and 1.0 (exclusive). Different numbers can be produced every time this function is invoked. Numbers should be produced with approximately equal probability. More
`xsd:dateTime NOW()`	Returns an XSD dateTime value for the current query execution. All calls to this function in any one query execution will return the same value. The exact moment returned is not specified. More
`xsd:integer YEAR(xsd:dateTime arg)`	Returns the year part of arg as an integer. This function corresponds to `fn:year-from-dateTime`. More
`xsd:integer MONTH(xsd:dateTime arg)`	Returns the month part of arg as an integer. This function corresponds to fn:month-from-dateTime. More
`xsd:integer DAY(xsd:dateTime arg)`	Returns the day part of arg as an integer. This function corresponds to `fn:day-from-dateTime`. More
`xsd:integer HOURS(xsd:dateTime arg)`	Returns the hours part of arg as an integer. The value is as given in the lexical form of the XSD dateTime. This function corresponds to `fn:hours-from-dateTime`. More
`xsd:integer MINUTES(xsd:dateTime arg)`	Returns the minutes part of the lexical form of arg. The value is as given in the lexical form of the XSD dateTime. This function corresponds to `fn:minutes-from-dateTime`. More
`xsd:decimal SECONDS(xsd:dateTime arg)`	Returns the seconds part of the lexical form of arg. This function corresponds to `fn:seconds-from-dateTime`. More
`xsd:dayTimeDuration TIMEZONE(xsd:dateTime arg)`	Returns the timezone part of arg as an xsd:dayTimeDuration. Raises an error if there is no timezone. This function corresponds to `fn:timezone-from-dateTime` except for the treatment of literals with no timezone. More
`xsd:string TZ(xsd:dateTime arg)`	Returns the timezone part of `arg` as a simple literal. Returns the empty string if there is no timezone. More
`xsd:string MD5(xsd:string arg)`	Returns the MD5 checksum, as a hex digit string, calculated on the UTF-8 representation of the lexical form of the argument. More
`xsd:string SHA1(xsd:string arg)`	Returns the SHA1 checksum, as a hex digit string, calculated on the UTF-8 representation of the lexical form of the argument. More
`xsd:string SHA256(xsd:string arg)`	Returns the SHA256 checksum, as a hex digit string, calculated on the UTF-8 representation of the lexical form of the argument. More
`xsd:string SHA512(xsd:string arg)`	Returns the SHA512 checksum, as a hex digit string, calculated on the UTF-8 representation of the lexical form of the argument. More

SPARQL 1.1 constructor functions ¶

Casting in SPARQL 1.1 is performed by calling a constructor function for the target type on an operand of the source type. The standard includes the following constructor functions:

Note

Note that SPARQL 1.1 does not have an xsd:date constructor. Instead, use STRDT(value,xsd:date) to attach the xsd:date datatype to the value.

Constructor function	Description
`literal STRDT(xsd:string lexicalForm, iri datatypeIRI)`	The STRDT function constructs a literal with lexical form and type as specified by the arguments. More
`xsd:langString STRLANG(xsd:string lexicalForm, xsd:string langTag)`	The STRLANG function constructs a literal with lexical form and language tag as specified by the arguments. More
`xsd:integer(rdfTerm value)`	Casts value to `xsd:integer`. More
`xsd:decimal(rdfTerm value)`	Casts value to `xsd:decimal`. More
`xsd:float(rdfTerm value)`	Casts value to `xsd:float`. More
`xsd:double(rdfTerm value)`	Casts value to `xsd:double`. More
`xsd:string(rdfTerm value)`	Casts value to `xsd:string`. More
`xsd:boolean(rdfTerm value)`	Casts value to `xsd:boolean`. More
`xsd:dateTime(rdfTerm value)`	Casts value to `xsd:dateTime`. More
`xsd:nonPositiveInteger(rdfTerm value)`	Casts value to `xsd:nonPositiveInteger`. More
`xsd:negativeInteger(rdfTerm value)`	Casts value to `xsd:negativeInteger`. More
`xsd:long(rdfTerm value)`	Casts value to `xsd:long`. More
`xsd:int(rdfTerm value)`	Casts value to `xsd:int`. More
`xsd:short(rdfTerm value)`	Casts value to `xsd:short`. More
`xsd:byte(rdfTerm value)`	Casts value to `xsd:byte`. More
`xsd:nonNegativeInteger(rdfTerm value)`	Casts value to `xsd:nonNegativeInteger`. More
`xsd:unsignedLong(rdfTerm value)`	Casts value to `xsd:unsignedLong`. More
`xsd:unsignedInt(rdfTerm value)`	Casts value to `xsd:unsignedInt`. More
`xsd:unsignedShort(rdfTerm value)`	Casts value to `xsd:unsignedShort`. More
`xsd:unsignedByte(rdfTerm value)`	Casts value to `xsd:unsignedByte`. More
`xsd:positiveInteger(rdfTerm value)`	Casts value to `xsd:positiveInteger`. More

Mathematical function extensions ¶

Beside the standard SPARQL functions operating on numbers, GraphDB offers several additional functions, allowing users to do more mathematical operations. These are implemented using Java’s Math class.

The prefix ofn: stands for the namespace <http://www.ontotext.com/sparql/functions/>.

Function	Description
`xsd:double ofn:acos(numeric a)`	The arccosine function. The input is in the range \([-1, +1]\). The output is in the range \([0, \pi]\) radians. See Math.acos(double). Example: `ofn:acos(0.5) = 1.0471975511965979`
`xsd:double ofn:asin(numeric a)`	The arcsine function. The input is in the range \([-1, +1]\). The output is in the range \([-\pi/2, \pi/2]\) radians. See Math.asin(double). Example: `ofn:asin(0.5) = 0.5235987755982989`
`xsd:double ofn:atan(numeric a)`	The arctangent function. The output is in the range \((-\pi/2, \pi/2)\) radians. See Math.atan(double). Example: `ofn:atan(1) = 0.7853981633974483`
`xsd:double ofn:atan2(numeric y, numeric x)`	The double-argument arctangent function (the angle component of the conversion from rectangular coordinates to polar coordinates). The output is in the range \([-\pi/2, \pi/2]\) radians. See Math.atan2(double,double). Example: `ofn:atan2(1, 0) = 1.5707963267948966`
`xsd:double ofn:cbrt(numeric a)`	The cubic root function. See Math.cbrt(double). Example: `ofn:cbrt(2) = 1.2599210498948732`
`xsd:double ofn:copySign(numeric magnitude, numeric sign)`	Returns the first floating-point argument with the sign of the second floating-point argument. See Math.copySign(double,double). Example: `ofn:copySign(2, -7.5) = -2.0`
`xsd:double ofn:cos(numeric a)`	The cosine function. The argument is in radians. See Math.cos(double). Example: `ofn:cos(1) = 0.5403023058681398`
`xsd:double ofn:cosh(numeric x)`.	The hyperbolic cosine function. See Math.cosh(double). Example: `ofn:cosh(1) = 1.543080634815244`
`xsd:double ofn:e()`	Returns the double value that is closer than any other to \(e\), the base of the natural logarithms. See Math.E. Example: `ofn:e() = 2.718281828459045`
`xsd:double ofn:exp(double a)`	The exponent function, \(e^x\). See Math.exp(double). Example: `ofn:exp(2) = 7.38905609893065`
`xsd:double ofn:expm1(numeric x)`	Returns \(e^x - 1\). See Math.expm1(double). Example: `ofn:expm1(3) = 19.085536923187668`
`xsd:double ofn:floorDiv(numeric x, numeric y)`	Returns the largest (closest to positive infinity) int value (as a double number) that is less than or equal to the algebraic quotient. The arguments are implicitly cast to long. See Math.floorDiv(long,long). Example: `ofn:floorDiv(5, 2) = 2.0`
`xsd:double ofn:floorMod(numeric x, numeric y)`	Returns the floor modulus (as a double number) of the arguments. The arguments are implicitly cast to long. See Math.floorMod(long,long). Example: `ofn:floorMod(10, 3) = 1.0`
`xsd:double ofn:getExponent(numeric d)`	Returns the unbiased exponent used in the representation of a double. This means that we take n from the binary representation of x: \(x = 1 \times 2^n + \{1\|0\} \times 2^{(n-1)} + ... + \{1\|0\} \times 2^0\), i.e., the power of the highest non-zero bit of the binary form of x. See Math.getExponent(double). Example: `ofn:getExponent(10) = 3.0`
`xsd:double ofn:hypot(numeric x, numeric y)`	Returns \(sqrt(x^2 +y^2)\) without intermediate overflow or underflow. See Math.hypot(double,double). Example: `ofn:hypot(3, 4) = 5.0`
`xsd:double ofn:IEEEremainder(numeric f1, numeric f2)`	Computes the remainder operation on two arguments as prescribed by the IEEE 754 standard. See Math.IEEEremainder(double,double). Example: `ofn:IEEEremainder(3, 4) = -1.0`
`xsd:double ofn:log(numeric a)`	The natural logarithm function. See Math.log(double). Example: `ofn:log(4) = 1.3862943611198906`
`xsd:double ofn:log10(numeric a)`.	The common (decimal) logarithm function. See Math.log10(double). Example: `ofn:log10(4) = 0.6020599913279624`
`xsd:double ofn:log1p(numeric x)`	Returns the natural logarithm of the sum of the argument and 1. See Math.log1p(double). Example: `ofn:log1p(4) = 1.6094379124341003`
`xsd:double ofn:max(numeric a, numeric b)`	The greater of two numbers. See Math.max(double,double). Example: `ofn:max(3, 5) = 5.0`
`xsd:double ofn:min(numeric a, numeric b)`	The smaller of two numbers. See Math.min(double,double). Example: `ofn:min(3, 5) = 3.0`
`xsd:double ofn:nextAfter(numeric start, numeric direction)`	Returns the floating-point number adjacent to the first argument in the direction of the second argument. See Math.nextAfter(double,double). Example: `ofn:nextAfter(2, -7) = 1.9999999999999998`
`xsd:double ofn:nextDown(numeric d)`	Returns the floating-point value adjacent to d in the direction of negative infinity. See Math.nextDown(double). Example: `ofn:nextDown(2) = 1.9999999999999998`
`xsd:double ofn:nextUp(numeric d)`	Returns the floating-point value adjacent to d in the direction of positive infinity. See Math.nextUp(double). Example: `ofn:nextUp(2) = 2.0000000000000004`
`xsd:double ofn:pi()`	Returns the double value that is closer than any other to \(\pi\), the ratio of the circumference of a circle to its diameter. See Math.PI. Example: `ofn:pi() = 3.141592653589793`
`xsd:double ofn:pow(numeric a, numeric b)`	The power function. See Math.pow(double,double). Example: `ofn:pow(2, 3) = 8.0`
`xsd:double ofn:rint(numeric a)`	Returns the double value that is closest in value to the argument and is equal to a mathematical integer. See Math.rint(double). Example: `ofn:rint(2.51) = 3.0`
`xsd:double ofn:scalb(numeric d, numeric scaleFactor)`	Returns \(d \times 2^{scaleFactor}\) rounded as if performed by a single correctly rounded floating-point multiply to a member of the double value set. See Math.scalb(double,int). `scaleFactor` can be negative, for example: `ofn:scalb(3, -3) = 3 * 2^-3 = 0.375`. Example: `ofn:scalb(3, 3) = 24.0`
`xsd:double ofn:signum(numeric d)`	Returns the signum function of the argument; zero if the argument is zero, 1.0 if the argument is greater than zero, -1.0 if the argument is less than zero. See Math.signum(double). Example: `ofn:signum(-5) = -1.0`
`xsd:double ofn:sin(numeric a)`	The sine function. The argument is in radians. See Math.sin(double). Example: `ofn:sin(2) = 0.9092974268256817`
`xsd:double ofn:sinh(numeric x)`	The hyperbolic sine function. See Math.sinh(double). Example: `ofn:sinh(2) = 3.626860407847019`
`xsd:double ofn:sqrt(numeric a)`	The square root function. See Math.sqrt(double). Example: `ofn:sqrt(2) = 1.4142135623730951d`
`xsd:double ofn:tan(numeric a)`	The tangent function. The argument is in radians. See Math.tan(double). Example: `ofn:tan(1) = 1.5574077246549023`
`xsd:double ofn:tanh(numeric x)`	The hyperbolic tangent function. See Math.tanh(double). Example: `ofn:tanh(1) = 0.7615941559557649`
`xsd:double ofn:toDegrees(numeric angrad)`	Converts an angle measured in radians to an approximately equivalent angle measured in degrees. See Math.toDegrees(double). Example: `ofn:toDegrees(1) = 57.29577951308232`
`xsd:double ofn:toRadians(numeric angdeg)`	Converts an angle measured in degrees to an approximately equivalent angle measured in radians. See Math.toRadians(double). Example: `ofn:toRadians(1) = 0.017453292519943295`
`xsd:double ofn:ulp(numeric d)`	Returns the size of an ulp of the argument. An ulp, unit in the last place, of a double value is the positive distance between this floating-point value and the double value next larger in magnitude. Note that for non-NaN x, ulp(-x) == ulp(x). See Math.ulp(double). Example: `ofn:ulp(1) = 2.220446049250313E-16`

GraphDB also supports several Jena ARQ simple function analogs. The prefix afn: stands for the namespace <http://jena.apache.org/ARQ/function#>.

Function	Description
`afn:min(num1, num2)`	Return the minimum of two numbers.
`afn:max(num1, num2)`	Return the maximum of two numbers.
`afn:pi()`	The value of pi as an XSD double.
`afn:e()`	The value of e as an XSD double.
`afn:sqrt(num)`	The square root of num.

Date and time function extensions ¶

Beside the standard SPARQL functions related to date and time, GraphDB offers several additional functions, allowing users to do more with their temporal data.

The prefix ofn: stands for the namespace <http://www.ontotext.com/sparql/functions/>. For more information, refer to Time Functions Extensions.

Function	Description
`xsd:long ofn:years-from-duration(xsd:duration dur)`	Return the “years” part of the duration literal
`xsd:long ofn:months-from-duration(xsd:duration dur)`	Returns the “months” part of the duration literal
`xsd:long ofn:days-from-duration(xsd:duration dur)`	Returns the “days” part of the duration literal
`xsd:long ofn:hours-from-duration(xsd:duration dur)`	Returns the “hours” part of the duration literal
`xsd:long ofn:minutes-from-duration(xsd:duration dur)`	Returns the “minutes” part of the duration literal
`xsd:long ofn:seconds-from-duration(xsd:duration dur)`	Returns the “seconds” part of the duration literal
`xsd:long ofn:millis-from-duration(xsd:duration dur)`	Returns the “milliseconds” part of the duration literal
`xsd:long ofn:asWeeks(xsd:duration dur)`	Returns the duration of the period as weeks
`xsd:long ofn:asDays(xsd:duration dur)`	Returns the duration of the period as days
`xsd:long ofn:asHours(xsd:duration dur)`	Returns the duration of the period as hours
`xsd:long ofn:asMinutes(xsd:duration dur)`	Returns the duration of the period as minutes
`xsd:long ofn:asSeconds(xsd:duration dur)`	Returns the duration of the period as seconds
`xsd:long ofn:asMillis(xsd:duration dur)`	Returns the duration of the period as milliseconds
`xsd:long ofn:weeksBetween(xsd:dateTime d1, xsd:dateTime d2)`	Returns the duration between the two dates as weeks
`xsd:long ofn:daysBetween(xsd:dateTime d1, xsd:dateTime d2)`	Returns the duration between the two dates as days
`xsd:long ofn:hoursBetween(xsd:dateTime d1, xsd:dateTime d2)`	Returns the duration between the two dates as hours
`xsd:long ofn:minutesBetween(xsd:dateTime d1, xsd:dateTime d2)`	Returns the duration between the two dates as minutes
`xsd:long ofn:secondsBetween(xsd:dateTime d1, xsd:dateTime d2)`	Returns the duration between the two dates as seconds
`xsd:long ofn:millisBetween(xsd:dateTime d1, xsd:dateTime d2)`	Returns the duration between the two dates as milliseconds

SPARQL SPIN functions ¶

The following SPIN SPARQL functions and magic predicates are available in GraphDB. The prefix spif: stands for the namespace <http://spinrdf.org/spif#>.

SPIN functions that work on text use 0-based indexes, unlike SPARQL’s functions, which use 1-based indexes.

	Function	Description
Dates	`spif:parseDate(xsd:string date, xsd:string format)`	Parses date using format with Java’s SimpleDateFormat
	`spif:dateFormat(xsd:dateTime date, xsd:string format)`	Formats date using format with Java SimpleDateFormat
	`xsd:long spif:currentTimeMillis()`	The current time in milliseconds since the epoch
	`xsd:long spif:timeMillis(xsd:dateTime date)`	The time in milliseconds since the epoch for the provided argument
Numbers	`numeric spif:mod(xsd:numeric dividend, xsd:numeric divisor)`	Remainder from integer division
	`xsd:string spif:decimalFormat(numeric number, xsd:string format)`	Formats number using format with Java’s DecimalFormat
	`xsd:double spif:random()`	Calls Java’s Math.random()
Strings	`xsd:string spif:trim(string str)`	Calls `String.trim()`
	`spif:generateUUID()`	UUID generation as a literal. Same as SPARQL’s `STRUUID()`.
	`spif:cast(literal value, iri type)`	Same as SPARQL’s `STRDT(STR(value), type)`. Does not do validation either.
	`xsd:int spif:indexOf(string str, string substr)`	Position of first occurrence of a substring. Note that SPIN functions that work on text use 0-based indexes, unlike SPARQL’s functions, which use 1-based indexes.
	`xsd:int spif:lastIndexOf(string str, string substr)`	Position of last occurrence of a substring. Note that SPIN functions that work on text use 0-based indexes, unlike SPARQL’s functions, which use 1-based indexes.
	`xsd:string spif:buildString(string template, arguments…)`	Builds a literal from a template, e.g. “foo {?2} bar {?1}” where `{?2}` will be replaced with second argument and `{?1}` will be replaced with the first argument after the template.
	`xsd:string spif:replaceAll(string str, xsd:string regexp, xsd:string flags)`	Calls Java `String.replaceAll`, same as SPARQL’s `REPLACE()`.
	`xsd:string spif:unCamelCase(string str)`	Converts camel-cased string to non-camel case string with spaces
	`xsd:string spif:upperCase(string str)`	Converts to upper case, similar to SPARQL’s `UCASE()` but disregarding the language tag from the input string
	`xsd:string spif:lowerCase(string str)`	Converts to lower case, similar to SPARQL’s `LCASE()` but disregarding the language tag from the input string
	`xsd:string spif:titleCase(string str)`	Converts to title case (each word starts with a capital). You can use this function to convert a multi-word string to string to CamelCase as suitable for a class name as follows: `replace(titleCase(?x)," ","")`. CamelCase is a convention that uses leading uppercase instead of space to delineate words. See `spif:unCamelCase()` for the opposite operation.
	`xsd:string spif:lowerTitleCase(string str)`	Converts to lower title case (each but the first word starts with a capital. You can use this function to convert a multi-word string to camelCase as suitable for a property as follows: `replace(lowerTitleCase(?x)," ","")`. CamelCase is a convention that uses leading uppercase instead of space to delineate words. See `spif:unCamelCase()` for the opposite operation.
IRIs	`xsd:string spif:encodeURL(string str)`	Calls `java.net.URLEncoder.encode`, similar to SPARQL’s `ENCODE_FOR_URI()` but not the same
	`xsd:string spif:decodeURL(string str)`	Calls `java.net.URLEncoder.decode`
	`iri spif:buildURI(string template, arguments…)`	Builds a URI from a template, e.g. “<urn:{?1}/{?2}>” where `{?2}` will be replaced with second argument and `{?1}` will be replaced with the first argument after the template. The template must begin with `<` and end with `>`
	`xsd:boolean spif:isValidURI(string str)`	According to some standards, note that it allows spaces too
Functions	`rdfTerm spif:invoke(iri function, arguments…)`	Invokes a function indirectly (supplied as an IRI) with the provided arguments
Functions	`xsd:boolean spif:canInvoke(iri function, arguments…)`	Checks if the given function can be invoked with the given arguments

There are three magic predicates: spif:split, spif:for, and spif:foreach.

Predicate	Description
`?result spif:split (?string ?regex)`	Takes two arguments: a string to split and a regex to split on. The current implementation uses Java’s `String.split()`.
`?result spif:for (?start ?end)`	Generates bindings from a given start integer value to another given end integer value.
`?result spif:foreach (?arg1 ?arg2 …)`	Generates bindings for the given arguments arg1, arg2 and so on.

RDF-star extension functions ¶

To avoid any parsing of an embedded triple, GraphDB introduces the following SPARQL functions:

Function	Description
`xsd:boolean rdf:isTriple(variable var)`	Checks if the variable var is bound to an embedded triple
`iri rdf:subject(variable var)` `iri rdf:predicate(variable var)` `rdfTerm rdf:object(variable var)`	Extracts the subject, predicate, or object from a variable bound to an embedded triple
`rdf:Statement(iri subj, iri pred, rdfTerm obj)`	Creates a new embedded statement with the provided values

See more about RDF-star/SPARQL-star syntax here.

RDF list function extensions ¶

GraphDB supports the below Jena list function analogs.

The prefix list: stands for the namespace <http://jena.apache.org/ARQ/list#>.

Function	Description
`list list:member member`	Membership of an RDF List (RDF Collection). Currently in GraphDB, if `list` is not bound or a constant, an error will be thrown; else evaluate for the list in the variable `list`. If `member` is a variable, generate solutions with `member` bound to each element of list. If `member` is bound or a constant expression, test to see if it is a member of `list`.
`list list:index (index member)`	Index of an RDF List (RDF Collection). Currently in GraphDB, if `list` is not bound or a constant, an error will be thrown; else evaluate for one particular list. The object is a list pair, either element can be bound, unbound or a fixed node. Unbound variables in the object list are bound by the property function.
`list list:length length`	Length of an RDF List (RDF Collection). Currently in GraphDB, if `list` is not bound or a constant, an error will be thrown; else evaluate for one particular list. The object is tested against or bound to the length of the list.

Note

The Jena behavior is that if list is not bound or a constant, the function finds and iterates all lists in the graph (can be slow). As mentioned above, currently, GraphDB does not provide support for unbound list. Support for it will be added with the coming releases.

Aggregation function extensions ¶

GraphDB supports the below Jena ARQ aggregate function analogs, which are modeled after the corresponding SQL aggregate functions.

The prefix agg: stands for the namespace <http://jena.apache.org/ARQ/function/aggregate#>.

agg:stdev
agg:stdev_samp
agg:stdev_pop
agg:variance
agg:var_samp
agg:var_pop

The stdev_pop() and stdev_samp() functions compute the population standard deviation and sample standard deviation, respectively, of the input values. (stdev() is an alias for stdev_samp()) Both functions evaluate all input rows matched by the query. The difference is that stdev_samp() is scaled by 1/(N-1) while stdev_pop() is scaled by 1/N.

The var_samp() and var_pop() functions compute the sample variance and population variance, respectively, of the input values. (variance() is an alias for variance_samp()) Both functions evaluate all input rows matched by the query. The difference is that variance_samp() is scaled by 1/(N-1) while variance_pop() is scaled by 1/N.

GeoSPARQL functions ¶

The following functions are defined by the GeoSPARQL standard. For more information, refer to OGC GeoSPARQL - A Geographic Query Language for RDF Data. The prefix geof: stands for the namespace <http://www.opengis.net/def/function/geosparql/>.

The type geomLiteral serves as a placeholder for any GeoSPARQL literal that describes a geometry. GraphDB supports WKT (datatype geo:wktLiteral) and GML (datatype geo:gmlLiteral).

Function	Description
`xsd:double geof:distance(geomLiteral geom1, geomLiteral geom2, iri units)`	Returns the shortest distance in units between any two Points in the two geometric objects as calculated in the spatial reference system of geom1.
`geomLiteral geof:buffer(geomLiteral geom, xsd:double radius, iri units)`	This function returns a geometric object that represents all Points whose distance from geom1 is less than or equal to the radius measured in units. Calculations are in the spatial reference system of geom1.
`geomLiteral geof:convexHull(geomLiteral geom1)`	This function returns a geometric object that represents all Points in the convex hull of geom1. Calculations are in the spatial reference system of geom1.
`geomLiteral geof:intersection(geomLiteral geom1, geomLiteral geom2)`	This function returns a geometric object that represents all Points in the intersection of geom1 with geom2. Calculations are in the spatial reference system of geom1.
`geomLiteral geof:union(geomLiteral geom1, geomLiteral geom2)`	This function returns a geometric object that represents all Points in the union of geom1 with geom2. Calculations are in the spatial reference system of geom1.
`geomLiteral geof:difference(geomLiteral geom1, geomLiteral geom2)`	This function returns a geometric object that represents all Points in the set difference of geom1 with geom2. Calculations are in the spatial reference system of geom1.
`geomLiteral geof:symDifference(geomLiteral geom1, geomLiteral geom2)`	This function returns a geometric object that represents all Points in the set symmetric difference of geom1 with geom2. Calculations are in the spatial reference system of geom1.
`geomLiteral geof:envelope(geomLiteral geom1)`	This function returns the minimum bounding box of geom1. Calculations are in the spatial reference system of geom1.
`geomLiteral geof:boundary(geomLiteral geom1)`	This function returns the closure of the boundary of geom1. Calculations are in the spatial reference system of geom1.
`iri geof:getSRID(geomLiteral geom)`	Returns the spatial reference system URI for geom.
`xsd:boolean geof:relate(geomLiteral geom1, geomLiteral geom2, xsd:string matrix)`	Returns true if the spatial relationship between geom1 and geom2 corresponds to one with acceptable values for the specified pattern-matrix. Otherwise, this function returns false. Pattern-matrix represents a DE-9IM intersection pattern consisting of T (true) and F (false) values. The spatial reference system for geom1 is used for spatial calculations.
`xsd:boolean geof:sfEquals(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TFFFTFFFT)`
`xsd:boolean geof:sfDisjoint(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(FFFF***)`
`xsd:boolean geof:sfIntersects(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(T******** T**** T** T**)`
`xsd:boolean geof:sfTouches(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(FT***** FT*** FT***)`
`xsd:boolean geof:sfCrosses(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TTT)` for P/L, P/A, L/A; `(0TT)` for L/L
`xsd:boolean geof:sfWithin(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TFF**)`
`xsd:boolean geof:sfContains(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(T****FF)`
`xsd:boolean geof:sfOverlaps(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TTT)` for A/A, P/P; `(1TT)` for L/L
`xsd:boolean geof:ehEquals(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TFFFTFFFT)`
`xsd:boolean geof:ehDisjoint(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(FFFF***)`
`xsd:boolean geof:ehMeet(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(FT***** FT*** FT***)`
`xsd:boolean geof:ehOverlap(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TTT)`
`xsd:boolean geof:ehCovers(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TTFTFF*)`
`xsd:boolean geof:ehCoveredBy(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TFFTFT*)`
`xsd:boolean geof:ehInside(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TFFFFT*)`
`xsd:boolean geof:ehContains(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TTFFFF*)`
`xsd:boolean geof:rcc8eq(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TFFFTFFFT)`
`xsd:boolean geof:rcc8dc(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(FFTFFTTTT)`
`xsd:boolean geof:rcc8ec(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(FFTFTTTTT)`
`xsd:boolean geof:rcc8po(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TTTTTTTTT)`
`xsd:boolean geof:rcc8tppi(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TTTFTTFFT)`
`xsd:Boolean geof:rcc8tpp(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TFFTTFTTT)`
`xsd:boolean geof:rcc8ntpp(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TFFTFFTTT)`
`xsd:boolean geof:rcc8ntppi(geomLiteral geom1, geomLiteral geom2)`	DE-9IM intersection pattern: `(TTTFFTFFT)`

GeoSPARQL extension functions ¶

On top of the standard GeoSPARQL functions, GraphDB adds a few useful extensions based on the USeekM library. The prefix ext: stands for the namespace <http://rdf.useekm.com/ext#>.

The types geo:Geometry, geo:Point, etc. refer to GeoSPARQL types in the http://www.opengis.net/ont/geosparql# namespace.

See more about GraphDB’s GeoSPARQL extensions here.

Function	Description
`xsd:double ext:area(geomLiteral g)`	Calculates the area of the surface of the geometry.
`geomLiteral ext:closestPoint(geomLiteral g1, geomLiteral g2)`	For two given geometries, computes the point on the first geometry that is closest to the second geometry.
`xsd:boolean ext:containsProperly(geomLiteral g1, geomLiteral g2)`	Tests if the first geometry properly contains the second geometry. Geom1 contains properly geom2 if all geom1 contains geom2 and the boundaries of the two geometries do not intersect.
`xsd:boolean ext:coveredBy(geomLiteral g1, geomLiteral g2)`	Tests if the first geometry is covered by the second geometry. Geom1 is covered by geom2 if every point of geom1 is a point of geom2.
`xsd:boolean ext:covers(geomLiteral g1, geomLiteral g2)`	Tests if the first geometry covers the second geometry. Geom1 covers geom2 if every point of geom2 is a point of geom1.
`xsd:double ext:hausdorffDistance(geomLiteral g1, geomLiteral g2)`	Measures the degree of similarity between two geometries. The measure is normalized to lie in the range [0, 1]. Higher measures indicate a greater degree of similarity.
`geo:Line ext:shortestLine(geomLiteral g1, geomLiteral g2)`	Computes the shortest line between two geometries. Returns it as a LineString object.
`geomLiteral ext:simplify(geomLiteral g, double d)`	Given a maximum deviation from the curve, computes a simplified version of the given geometry using the Douglas-Peuker algorithm.
`geomLiteral ext:simplifyPreserveTopology(geomLiteral g, double d)`	Given a maximum deviation from the curve, computes a simplified version of the given geometry using the Douglas-Peuker algorithm. Will avoid creating derived geometries (polygons in particular) that are invalid.
`xsd:boolean ext:isValid(geomLiteral g)`	Checks whether the input geometry is a valid geometry.

Geospatial extension functions ¶

At present, there is just one SPARQL extension function. The prefix omgeo: stands for the namespace <http://www.ontotext.com/owlim/geo#>.

Function	Description
`xsd:double omgeo:distance(numeric lat1, numeric long1, numeric lat2, numeric long2)`	Computes the distance between two points in kilometers and can be used in `FILTER` and `ORDER BY` clauses. Latitude is limited to the range -90 (South) to +90 (North). Longitude is limited to the range -180 (West) to +180 (East).

Function

Description

xsd:double omgeo:distance(numeric lat1, numeric long1, numeric lat2, numeric long2)

Computes the distance between two points in kilometers and can be used in FILTER and ORDER BY clauses.

Latitude is limited to the range -90 (South) to +90 (North). Longitude is limited to the range -180 (West) to +180 (East).

See more about GraphDB’s geospatial extensions here.

Other function extensions ¶

Below are additional Jena function analogs supported by GraphDB.

The prefix afn: stands for the namespace <http://jena.apache.org/ARQ/function#>.

Function	Description
`iri apf:splitIRI (namespace localname)` `iri apf:splitURI (namespace localname)`	Split the IRI or URI into namespace (an IRI) and local name (a string). Compare if given values or bound variables, otherwise set the variable. The object is a list with 2 elements. `splitURI` is a synonym.
`var apf:concat (arg arg …)`	Concatenate the arguments in the object list as strings, and assign to `var`.
`var apf:strSplit (arg arg)`	Split a string and return a binding for each result. The subject variable should be unbound. The first argument to the object list is the string to be split. The second argument to the object list is a regular expression by which to split the string. The subject `var` is bound for each result of the split, and each result has the whitespace trimmed from it.
`afn:bnode(?x)`	Return the blank node label if `?x` is a blank node.
`afn:localname(?x)`	The local name of `?x`.
`afn:namespace(?x)`	The namespace of `?x`.
`afn:sprintf(format, v1, v2, …)`	Make a string from the format string and the RDF terms.
`afn:substr(string, startIndex [,endIndex])`	Substring, Java style using `startIndex` and `endIndex`.
`afn:substring`	Synonym for `afn:substr`.
`afn:strjoin(sep, string …)`	Concatenate given strings, using `sep` as a separator.
`afn:sha1sum(resource)`	Calculate the SHA1 checksum of a literal or URI.
`afn:now()`	Current time. (Actually, a fixed moment of the current query execution – see the standard function `NOW()` for details.)