[ https://issues.apache.org/jira/browse/ARROW-6184?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Micah Kornfield resolved ARROW-6184. ------------------------------------ Fix Version/s: 1.0.0 Resolution: Fixed Issue resolved by pull request 5058 [https://github.com/apache/arrow/pull/5058] > [Java] Provide hash table based dictionary encoder > -------------------------------------------------- > > Key: ARROW-6184 > URL: https://issues.apache.org/jira/browse/ARROW-6184 > Project: Apache Arrow > Issue Type: New Feature > Components: Java > Reporter: Liya Fan > Assignee: Liya Fan > Priority: Major > Labels: pull-request-available > Fix For: 1.0.0 > > Time Spent: 5h > Remaining Estimate: 0h > > This is the second part of ARROW-5917. We provide a sort based encoder, as > well as a hash table based encoder, to solve the problem with the current > dictionary encoder. > In particular, we solve the following problems with the current encoder: > # There are repeated conversions between Java objects and bytes (e.g. > vector.getObject(i)). > # Unnecessary memory copy (the vector data must be copied to the hash table). > # The hash table cannot be reused for encoding multiple vectors (other data > structure & results cannot be reused either). > # The output vector should not be created/managed by the encoder (just like > in the out-of-place sorter) > # The hash table requires that the hashCode & equals methods be implemented > appropriately, but this is not guaranteed. -- This message was sent by Atlassian Jira (v8.3.4#803005)