Method copy

core/src/main/java/org/apache/calcite/rel/RelNode.java:374–374

Creates a copy of this relational expression, perhaps changing traits and inputs. Sub-classes with other important attributes are encouraged to create variants of this method with more parameters. @param traitSet Trait set @param inputs Inputs @return Copy of this relational expression, subst

(
      RelTraitSet traitSet,
      List<RelNode> inputs)

   * inputs
   */
  RelNode copy(
      RelTraitSet traitSet,
      List<RelNode> inputs);