How to use

projectsOnlyIdentity

method

in

org.apache.calcite.rex.RexProgram

/**
 * Returns whether this program returns its input exactly.
 *
 * <p>This is a stronger condition than {@link #projectsIdentity(boolean)}.
 */
public boolean isTrivial() {
 return getCondition() == null && projectsOnlyIdentity();
}

/**
 * Returns whether this program returns its input exactly.
 *
 * <p>This is a stronger condition than {@link #projectsIdentity(boolean)}.
 */
public boolean isTrivial() {
 return getCondition() == null && projectsOnlyIdentity();
}

 @Override protected RelNode handle(RelNode rel) {
  if (!(rel instanceof LogicalCalc)) {
   return rel;
  }
  final LogicalCalc calc = (LogicalCalc) rel;
  final RexProgram program = calc.getProgram();
  relBuilder.push(calc.getInput());
  if (program.getCondition() != null) {
   relBuilder.filter(
     program.expandLocalRef(program.getCondition()));
  }
  if (!program.projectsOnlyIdentity()) {
   relBuilder.project(
     Lists.transform(program.getProjectList(),
       program::expandLocalRef),
     calc.getRowType().getFieldNames());
  }
  return relBuilder.build();
 }
};

 @Override protected RelNode handle(RelNode rel) {
  if (!(rel instanceof LogicalCalc)) {
   return rel;
  }
  final LogicalCalc calc = (LogicalCalc) rel;
  final RexProgram program = calc.getProgram();
  relBuilder.push(calc.getInput());
  if (program.getCondition() != null) {
   relBuilder.filter(
     program.expandLocalRef(program.getCondition()));
  }
  if (!program.projectsOnlyIdentity()) {
   relBuilder.project(
     Lists.transform(program.getProjectList(),
       program::expandLocalRef),
     calc.getRowType().getFieldNames());
  }
  return relBuilder.build();
 }
};