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SPARQL FILTER Functions ​

This page summarizes the standard built-in functions commonly used inside FILTER, BIND, ORDER BY, HAVING, and projected expressions.

String functions ​

  • STR(term)
  • LANG(literal)
  • LANGMATCHES(tag, pattern)
  • DATATYPE(literal)
  • BOUND(?var)
  • IRI(string) / URI(string)
  • BNODE() / BNODE(string)
  • STRDT(string, datatypeIri)
  • STRLANG(string, langTag)
  • UUID() / STRUUID()
  • STRLEN(string)
  • SUBSTR(string, start[, length])
  • UCASE(string)
  • LCASE(string)
  • STRSTARTS(string, prefix)
  • STRENDS(string, suffix)
  • CONTAINS(string, substring)
  • STRBEFORE(string, substring)
  • STRAFTER(string, substring)
  • ENCODE_FOR_URI(string)
  • CONCAT(a, b, ...)
  • REGEX(text, pattern[, flags])
  • REPLACE(text, pattern, replacement[, flags])

Numeric functions ​

  • ABS(number)
  • ROUND(number)
  • CEIL(number)
  • FLOOR(number)
  • RAND()

Date/time extraction ​

  • NOW()
  • YEAR(dateTime)
  • MONTH(dateTime)
  • DAY(dateTime)
  • HOURS(dateTime)
  • MINUTES(dateTime)
  • SECONDS(dateTime)
  • TIMEZONE(dateTime)
  • TZ(dateTime)

Hash functions ​

  • MD5(string)
  • SHA1(string)
  • SHA256(string)
  • SHA384(string)
  • SHA512(string)

Term tests ​

  • isIRI(term) / isURI(term)
  • isBLANK(term)
  • isLITERAL(term)
  • isNUMERIC(term)
  • sameTerm(a, b)

Conditional and error-handling functions ​

  • IF(condition, whenTrue, whenFalse)
  • COALESCE(a, b, ...)

Existence tests ​

  • EXISTS { ... }
  • NOT EXISTS { ... }

Examples ​

String matching ​

sparql
FILTER(CONTAINS(LCASE(STR(?label)), "road"))
FILTER(REGEX(STR(?identifier), "^urn:", "i"))

Optional values ​

sparql
FILTER(BOUND(?comment))
FILTER(COALESCE(?score, 0) > 5)

Language-aware labels ​

sparql
FILTER(LANGMATCHES(LANG(?label), "en"))

Conditional logic ​

sparql
BIND(IF(?score >= 90, "high", "normal") AS ?band)

Notes ​

  • STR() converts an RDF term to its lexical string form.
  • REGEX flags are strings such as "i".
  • BOUND requires a variable, not a literal.
  • sameTerm compares RDF terms directly, including IRIs.

Reference ​