| /* |
| * 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.drill.exec.physical.impl.window; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * Used internally to keep track of partitions and frames.<p> |
| * A partition can be partial, which means we don't know "yet" the total number |
| * of records that are part of this partition. Even for partial partitions, we |
| * know the number of rows that are part of current frame |
| */ |
| public class Partition { |
| private static final Logger logger = LoggerFactory.getLogger(Partition.class); |
| |
| private boolean partial; // true if we don't know yet the full length of this partition |
| private long length; // size of this partition (if partial is true, then this is a partial length of the partition) |
| private long remaining; // remaining non-processed rows in this partition |
| |
| private long peers; // remaining non-processed peers in current frame |
| |
| // we keep these attributes public because the generated code needs to access them |
| public int row_number = 1; |
| public int rank; |
| public int dense_rank; |
| public double percent_rank; |
| public double cume_dist; |
| |
| /** |
| * @return number of rows not yet aggregated in this partition |
| */ |
| public long getRemaining() { |
| return remaining; |
| } |
| |
| public long getLength() { |
| return length; |
| } |
| |
| /** |
| * @param length |
| * number of rows in this partition |
| * @param partial |
| * if true, then length is not the full length of the partition but |
| * just the number of rows in the current batch |
| */ |
| public void updateLength(long length, boolean partial) { |
| this.length += length; |
| this.partial = partial; |
| remaining += length; |
| } |
| |
| public void rowAggregated() { |
| remaining--; |
| peers--; |
| row_number++; |
| } |
| |
| public void newFrame(long peers) { |
| this.peers = peers; |
| |
| rank = row_number; // rank = row number of 1st peer |
| dense_rank++; |
| percent_rank = length > 1 ? (double) (rank - 1) / (length - 1) : 0; |
| cume_dist = (double)(rank + peers - 1) / length; |
| } |
| |
| public boolean isDone() { |
| return !partial && remaining == 0; |
| } |
| |
| public int ntile(int numTiles) { |
| long mod = length % numTiles; |
| double ceil = Math.ceil((double) length / numTiles); |
| |
| int out; |
| if (row_number <= mod * ceil) { |
| out = (int) Math.ceil(row_number / ceil); |
| } else { |
| double floor = Math.floor((double) length / numTiles); |
| out = (int) Math.ceil((row_number - mod) / floor); |
| } |
| |
| logger.trace("NTILE(row_number = {}, nt = {}, ct = {}) = {}", row_number, numTiles, length, out); |
| return out; |
| } |
| |
| public boolean isFrameDone() { |
| return peers == 0; |
| } |
| |
| @Override |
| public String toString() { |
| return String.format("{length: %d, remaining partition: %d, remaining peers: %d}", length, remaining, peers); |
| } |
| } |