Package com.sap.cds.ql.cqn.transformation

Interface CqnTopLevelsTransformation

All Superinterfaces:
CqnTransformation
@Beta public interface CqnTopLevelsTransformation extends CqnTransformation
Transformation that determines top level instances that belong to a recursive hierarchy. The hierarchy is defined by the hierarchy reference and the hierarchy qualifier. The transformation takes an input set consisting of instances that belong to the hierarchy. The output retains nodes of the top n levels(), i.e. nodes with less then n ancestors.

  • Method Details

    • hierarchyReference

      CqnStructuredTypeRef hierarchyReference()
      Returns a reference, which identifies the entities that form a recursive hierarchy. The entity is annotated with RecursiveHierarchy with a qualifier whose value is given by the hierarchyQualifier() method.
      Returns:
      a reference, which identifies the entities that form a recursive hierarchy

    • hierarchyQualifier

      String hierarchyQualifier()
      Returns the qualifier of the RecursiveHierarchy annotation
      Returns:
      the hierarchy qualifier

    • nodeProperty

      CqnElementRef nodeProperty()
      Returns a reference to the property that identifies the nodes of the hierarchy.
      Returns:
      a reference to the node property

    • levels

      long levels()
      Returns the number of levels, which the output set should contain
      Returns:
      the number of levels or -1 if unlimited

    • kind

      default CqnTransformation.Kind kind()
      Description copied from interface: CqnTransformation
      Returns the kind of this transformation
      Specified by:
      kind in interface CqnTransformation
      Returns:
      the kind of this transformation