确定SPARQL中的日期时间

此外,大多数SPARQL引擎都提供添加自定义功能的选项.

因此,您可以只检索dateTime并对结果进行后处理以获取星期几,也可以实际创建自定义函数并将其添加到SPARQL引擎中.这是一个关于如何使用Sesame/RDF4J向SPARQL添加自定义函数的教程.

如果您提供了一些背景知识，也可以确定标准SPARQL中的星期几。查询需要在您的日期之前的参考日期和该日期的星期几。

PREFIX xsd:  

SELECT ?date ?dayName
WHERE {
  # Sample dates
  VALUES ?date {
    "1961-08-04"^^xsd:date
    "1986-04-03"^^xsd:date
  }
  # Compute days since a reference date
  # This works in Virtuoso, which returns the difference in days.
  # For example, Fuseki returns xsd:duration instead.
  BIND (?date - "1900-01-01"^^xsd:date AS ?days)
  # Compute modulo by 7 without a modulo operator
  BIND (floor(?days - (7 * floor(?days/7))) AS ?mod)
  VALUES (?mod ?dayName) {
         (0    "Monday") # 1900-01-01 was Monday
         (6    "Tuesday")
         (5    "Wednesday")
         (4    "Thursday")
         (3    "Friday")
         (2    "Saturday")
         (1    "Sunday")
  }
}