diff --git a/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/sx/graph/SparkResolveRelation.scala b/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/sx/graph/SparkResolveRelation.scala
index 6ee575e2a..11d026f02 100644
--- a/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/sx/graph/SparkResolveRelation.scala
+++ b/dhp-workflows/dhp-graph-mapper/src/main/java/eu/dnetlib/dhp/sx/graph/SparkResolveRelation.scala
@@ -4,7 +4,12 @@ import eu.dnetlib.dhp.application.ArgumentApplicationParser
 import eu.dnetlib.dhp.schema.oaf.{Relation, Result}
 import org.apache.commons.io.IOUtils
 import org.apache.spark.SparkConf
+import org.apache.spark.rdd.RDD
 import org.apache.spark.sql._
+import org.json4s
+import org.json4s.DefaultFormats
+import org.json4s.JsonAST.{JField, JObject, JString}
+import org.json4s.jackson.JsonMethods.parse
 import org.slf4j.{Logger, LoggerFactory}
 
 import scala.collection.JavaConverters._
@@ -29,23 +34,11 @@ object SparkResolveRelation {
     val workingPath = parser.get("workingPath")
     log.info(s"workingPath  -> $workingPath")
 
-
-    implicit  val oafEncoder: Encoder[Result] = Encoders.kryo(classOf[Result])
     implicit  val relEncoder: Encoder[Relation] = Encoders.kryo(classOf[Relation])
     import spark.implicits._
-    val entities:Dataset[Result] = spark.read.load(s"$entityPath/*").as[Result]
 
-    entities.flatMap(e => e.getPid.asScala
-      .map(p =>
-             convertPidToDNETIdentifier(p.getValue, p.getQualifier.getClassid))
-            .filter(s => s!= null)
-            .map(s => (s,e.getId))
-    ).groupByKey(_._1)
-      .reduceGroups((x,y) => if (x._2.startsWith("50|doi") || x._2.startsWith("50|pmid")) x else y)
-      .map(s =>s._2)
-      .write
-      .mode(SaveMode.Overwrite)
-      .save(s"$workingPath/resolvedPid")
+
+    extractPidResolvedTableFromJsonRDD(spark, entityPath, workingPath)
 
     val rPid:Dataset[(String,String)] = spark.read.load(s"$workingPath/resolvedPid").as[(String,String)]
 
@@ -74,11 +67,65 @@ object SparkResolveRelation {
     }.filter(r => r.getSource.startsWith("50")&& r.getTarget.startsWith("50"))
       .write
       .mode(SaveMode.Overwrite)
-      .save(s"$workingPath/resolvedRelation")
+      .save(s"$workingPath/relation")
   }
 
 
+  private def extractPidsFromRecord(input:String):(String,List[(String,String)]) = {
+    implicit lazy val formats: DefaultFormats.type = org.json4s.DefaultFormats
+    lazy val json: json4s.JValue = parse(input)
+    val id:String = (json \ "id").extract[String]
+    val result: List[(String,String)] = for {
+      JObject(pids) <- json \ "pid"
+      JField("value", JString(pidValue)) <- pids
+      JField("qualifier", JObject(qualifier)) <- pids
+      JField("classname", JString(pidType)) <- qualifier
+    } yield (pidValue, pidType)
+    (id,result)
+  }
 
+  private def extractPidResolvedTableFromJsonRDD(spark: SparkSession, entityPath: String, workingPath: String) = {
+    import spark.implicits._
+
+    val d: RDD[(String,String)] = spark.sparkContext.textFile(s"$entityPath/*")
+      .map(i => extractPidsFromRecord(i))
+      .filter(s => s != null && s._2!=null && s._2.nonEmpty)
+      .flatMap{ p =>
+                  p._2.map(pid =>
+                    (p._1,convertPidToDNETIdentifier(pid._1, pid._2))
+                  )
+      }
+
+    spark.createDataset(d)
+    .groupByKey(_._1)
+      .reduceGroups((x, y) => if (x._2.startsWith("50|doi") || x._2.startsWith("50|pmid")) x else y)
+      .map(s => s._2)
+      .write
+      .mode(SaveMode.Overwrite)
+      .save(s"$workingPath/resolvedPid")
+  }
+
+
+  /*
+    This method should be used once we finally convert everythings in Kryo dataset
+    instead of using rdd of json
+   */
+  private def extractPidResolvedTableFromKryo(spark: SparkSession, entityPath: String, workingPath: String) = {
+    import spark.implicits._
+    implicit val oafEncoder: Encoder[Result] = Encoders.kryo(classOf[Result])
+    val entities: Dataset[Result] = spark.read.load(s"$entityPath/*").as[Result]
+    entities.flatMap(e => e.getPid.asScala
+      .map(p =>
+        convertPidToDNETIdentifier(p.getValue, p.getQualifier.getClassid))
+      .filter(s => s != null)
+      .map(s => (s, e.getId))
+    ).groupByKey(_._1)
+      .reduceGroups((x, y) => if (x._2.startsWith("50|doi") || x._2.startsWith("50|pmid")) x else y)
+      .map(s => s._2)
+      .write
+      .mode(SaveMode.Overwrite)
+      .save(s"$workingPath/resolvedPid")
+  }
 
   def convertPidToDNETIdentifier(pid:String, pidType: String):String = {
     if (pid==null || pid.isEmpty || pidType== null || pidType.isEmpty)