Sparql:如何按多列分组 [英] Sparql: how to GROUP BY More Than One Column

问题描述

在SPARQL中，我们可以通过以下语法将行按列分组:

In SPARQL, we can group the rows by a column through the gollowing syntax:

GROUP BY ?colName

我们可以按1列以上分组吗?

Can we group by more than 1 columns eg:

GROUP BY (?colName1 + ?colName2 + ?colName3) 

假设查询如下:

Select ?a ?b ?c (MIN(?y) AS ?d)
Where {
....
}
GROUP BY (?a + ?b + ?c)

但是此查询不起作用.

推荐答案

您可以通过以下方式列出GROUP BY多个变量(而不是列)，并在它们之间留一个空格:

You can GROUP BY multiple variables (not columns) by listing them with a space in between:

GROUP BY ?a ?b ?c

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