Interface AggCallPlus

core/src/main/java/org/apache/calcite/tools/RelBuilder.java:4400–4418

Internal methods shared by all implementations of AggCall.

  /** Internal methods shared by all implementations of {@link AggCall}. */
  private interface AggCallPlus extends AggCall {
    /** Returns the aggregate function. */
    SqlAggFunction op();

    /** Returns the alias. */
    @Nullable String alias();

    /** Returns an {@link AggregateCall} that is approximately equivalent
     * to this {@code AggCall} and is good for certain things, such as deriving
     * field names. */
    AggregateCall aggregateCall();

    /** Converts this {@code AggCall} to a good {@link AggregateCall}. */
    AggregateCall aggregateCall(Registrar registrar, boolean hasEmptyGroup,
        RelNode r);

    /** Registers expressions in operands and filters. */
    void register(Registrar registrar);
  }

  /** Information necessary to create the GROUP BY clause of an Aggregate.
   *