This web page is a companion to the “SPARQL query processing with Apache Spark” paper submitted at EDBT 2017.

It provides access to some resources related to the evaluation section.

Chain queries over DBPedia data set.

Using the SPARQL DF method:

val P2 = 52239
val P3 = 1164541952
val P4 = 1164156928
val t1 = df.where("p in (1389363200, 18843, 1089470464, 18970)").select("s","o").withColumnRenamed("s", "x1").withColumnRenamed("o", "x2")
val t2 = df.where(s"p=$P2").select("s","o").withColumnRenamed("s", "x2").withColumnRenamed("o", "x3")
val t3 = df.where(s"p=$P3").select("s","o").withColumnRenamed("s", "x3").withColumnRenamed("o", "x4")
val t4 = df.where(s"p=$P4").select("s","o").withColumnRenamed("s", "x4").withColumnRenamed("o", "x5")
val res = t1.join(t2,Seq("x2")).join(t3,Seq("x3")).join(t4,Seq("x4"))