Hi Benjamin, As you mentioned hash join I assume that you are referring to `HashJoinOperator` in blink planner.
The input is selected by `nextSelection` method. As you can see, it will first read all records in the build side then read all records in the probe side. So the probing will only start after the build side has been fully received. Apart from this specific question, I'm interested in how you're going to implement a hash join where any of the two sides can be read. Could you share your ideas or give some hints about this? Thanks a lot. Benjamin Burkhardt <pri...@benjaminburkhardt.de> 于2019年7月24日周三 上午1:24写道： > Hi all, > > Let’s imagine a simple repartition hash Join oft two tables. > > As soon as the first table is hashed completely (all EndOfPartition Events > sent) the shipping and probing of the second table starts. > > What I can’t find: > > 1. What triggers to start the probing exactly? > 2. Where can I find it in the code? > > > My final goal is to change the 2-phase join mechanism to a mixed > implementation where probing for finished subpartitions begins earlier. > > I appreciate any help. > > Thanks. > > Benjamin >
