[jira] [Issue Comment Deleted] (CASSANDRA-12910) SASI: calculatePrimary() always returns null

["Alex Petrov (JIRA)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/CASSANDRA-12910?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Alex Petrov updated CASSANDRA-12910:
------------------------------------
    Comment: was deleted

(was: Committed as [7b1e2ed6e3d97e445cfdc877b190feafa1550fd5|https://github.com/apache/cassandra/commit/7b1e2ed6e3d97e445cfdc877b190feafa1550fd5].)

> SASI: calculatePrimary() always returns null
> --------------------------------------------
>
>                 Key: CASSANDRA-12910
>                 URL: https://issues.apache.org/jira/browse/CASSANDRA-12910
>             Project: Cassandra
>          Issue Type: Bug
>          Components: sasi
>            Reporter: Corentin Chary
>            Assignee: Corentin Chary
>            Priority: Minor
>             Fix For: 3.12
>
>         Attachments: 0002-sasi-fix-calculatePrimary.patch
>
>
> While investigating performance issues with SASI  (https://github.com/criteo/biggraphite/issues/174 if you want to know more) I ended finding calculatePrimary() in QueryController.java which apparently should return the "primary index".
> It lacks documentation, and I'm unsure what the "primary index" should be, but apparently this function never returns one because primaryIndexes.size() is always 0.
> https://github.com/apache/cassandra/blob/81f6c784ce967fadb6ed7f58de1328e713eaf53c/src/java/org/apache/cassandra/index/sasi/plan/QueryController.java#L237
> I'm unsure if the proper fix is checking if the collection is empty or reversing the operator (selecting the index with higher cardinality versus the one with lower cardinality).



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)