amansinha100 commented on a change in pull request #1334: DRILL-6385: Support JPPD feature URL: https://github.com/apache/drill/pull/1334#discussion_r204465253
########## File path: exec/java-exec/src/main/java/org/apache/drill/exec/work/filter/BloomFilterCreator.java ########## @@ -0,0 +1,41 @@ +/* + * 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.work.filter; + +import io.netty.buffer.DrillBuf; +import org.apache.drill.exec.memory.BufferAllocator; + +public class BloomFilterCreator { Review comment: Could you pls add a description either here or another appropriate place about how the BF creation works for a generalized multi-column join.. e.g t1.a1 = t2.a2 AND t1.b1 = t2.b2. In this case, assume t2 is the build side. My understanding is as follows: - create a compound hash value using both build side columns: hash(a2, hash(b2)) (this may not be the exact way it is being created but same general idea). - add this to the BF, setting appropriate bits to 1 - on probe side, do the same for a1, b1 and check BF for either false/possibly true Let me know if this is correct. This also implies that the size of BF is independent of the number of columns being joined. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
