Chapter 2

Expressions

Transform and manipulate data with SPARQL's powerful expression functions. Work with strings, dates, numbers, and hashes to extract precisely the information you need.

Working with Expressions

SPARQL expressions allow you to transform, filter, and compute new values from your query results. Whether you need to extract a year from a date, concatenate strings, perform calculations, or generate identifiers, expression functions provide the tools you need.

Expressions are used in FILTER clauses, BIND statements, and SELECT projections to manipulate and derive new data.

Function Categories

📝

String Functions

Manipulate text with functions like CONCAT, SUBSTR, STRLEN, REPLACE, UCASE, LCASE, CONTAINS, STRSTARTS, STRENDS, and more.

Intermediate 15+ functions

Explore Strings

📅

Date Functions

Work with temporal data using YEAR, MONTH, DAY, HOURS, MINUTES, SECONDS, TIMEZONE, and NOW functions.

Intermediate Date & Time

Explore Dates

🔢

Math Functions

Perform calculations with ABS, ROUND, CEIL, FLOOR, RAND, and arithmetic operators (+, -, *, /).

Intermediate Numeric ops

Explore Math

🔐

Hash Functions

Generate identifiers and checksums with MD5, SHA1, SHA256, SHA384, and SHA512 hash functions.

Intermediate Cryptographic

Explore Hashes

Quick Examples

String Manipulation

Extract and Transform Text

Run ↗

SELECT ?lang ?langLabel
       (UCASE(?langLabel) AS ?upperName)
       (STRLEN(?langLabel) AS ?nameLength)
WHERE {
  ?lang wdt:P31 wd:Q9143 .
  SERVICE wikibase:label {
    bd:serviceParam wikibase:language "en" .
  }
}
LIMIT 10

Expressions Functions: UCASE, STRLEN

Date Extraction

Extract Year from Date

Run ↗

SELECT ?lang ?langLabel ?inception
       (YEAR(?inception) AS ?year)
       (MONTH(?inception) AS ?month)
WHERE {
  ?lang wdt:P31 wd:Q9143 ;
        wdt:P571 ?inception .
  SERVICE wikibase:label {
    bd:serviceParam wikibase:language "en" .
  }
}
ORDER BY DESC(?inception)
LIMIT 10

Expressions Functions: YEAR, MONTH

Mathematical Calculations

Calculate Age of Programming Languages

Run ↗

SELECT ?langLabel ?inception
       (YEAR(NOW()) - YEAR(?inception) AS ?age)
WHERE {
  ?lang wdt:P31 wd:Q9143 ;
        wdt:P571 ?inception .
  SERVICE wikibase:label {
    bd:serviceParam wikibase:language "en" .
  }
}
ORDER BY DESC(?age)
LIMIT 10

Expressions Functions: NOW, YEAR, arithmetic

Common Functions Reference

Function	Category	Description
`STR()`	String	Convert to string
`CONCAT()`	String	Concatenate strings
`SUBSTR()`	String	Extract substring
`UCASE() / LCASE()`	String	Convert case
`YEAR() / MONTH() / DAY()`	Date	Extract date components
`NOW()`	Date	Current datetime
`ABS() / ROUND() / FLOOR() / CEIL()`	Math	Numeric operations
`MD5() / SHA256()`	Hash	Generate hash

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📘

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📊

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Learn to analyze data with COUNT, SUM, and GROUP BY.

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