You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@drill.apache.org by "Igor Guzenko (JIRA)" <ji...@apache.org> on 2019/03/12 15:00:00 UTC
[jira] [Created] (DRILL-7096) Develop vector for canonical Map
Igor Guzenko created DRILL-7096:
-----------------------------------
Summary: Develop vector for canonical Map<K,V>
Key: DRILL-7096
URL: https://issues.apache.org/jira/browse/DRILL-7096
Project: Apache Drill
Issue Type: Improvement
Reporter: Igor Guzenko
Assignee: Igor Guzenko
Canonical Map<K,V> datatype can be represented using combination of three value vectors:
keysVector - vector for storing keys of each map
valuesVector - vector for storing values of each map
offsetsVector - vector for storing of start indexes of next each map
So it's not very hard to create such Map vector, but there is a major issue with such map representation. It's hard to search maps values by key in such vector, need to investigate some advanced techniques to make such search efficient. Or find other more suitable options to represent map datatype in world of vectors.
After question about maps, Apache Arrow developers responded that for Java they don't have real Map vector, for now they just have logical Map type definition where they define Map like: List< Struct<key:key_type, value:value_type> >. So implementation of value vector would be useful for Arrow too.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)