| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to you under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.calcite.sql; |
| |
| import org.apache.calcite.rel.core.AggregateCall; |
| import org.apache.calcite.rex.RexBuilder; |
| import org.apache.calcite.rex.RexNode; |
| import org.apache.calcite.util.ImmutableBitSet; |
| |
| import com.google.common.collect.ImmutableList; |
| |
| import org.checkerframework.checker.nullness.qual.Nullable; |
| |
| /** Aggregate function whose value may be a constant expression, based on |
| * only the contents of the GROUP BY clause. */ |
| public interface SqlStaticAggFunction { |
| /** Generates an expression for the aggregate function; or null if the value |
| * is not constant. |
| * |
| * <p>For example: |
| * <ul> |
| * <li>{@code GROUPING(deptno)} expands to literal {@code 1} |
| * if the aggregate has {@code GROUP BY deptno} |
| * </ul> |
| * |
| * @param rexBuilder Rex builder |
| * @param groupSet Group set |
| * @param groupSets Group sets |
| * @param aggregateCall Aggregate call |
| * |
| * @return Expression for single row |
| */ |
| @Nullable RexNode constant(RexBuilder rexBuilder, ImmutableBitSet groupSet, |
| ImmutableList<ImmutableBitSet> groupSets, AggregateCall aggregateCall); |
| } |