[jira] [Commented] (KYLIN-5997) Errors in building and querying real-time models

["Guoliang Sun (Jira)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/KYLIN-5997?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17927995#comment-17927995 ] 

Guoliang Sun commented on KYLIN-5997:
-------------------------------------

h3. Root Cause

During the modification of the snapshot response logic for internal tables, the logic for `tableScan` was incorrectly altered, causing queries on pure streaming models to trigger NPE (Null Pointer Exception) issues.

During the modification of the snapshot response logic for internal tables, the code logic was optimized by replacing null checks with `isEmpty`. However, in certain scenarios, calling `isEmpty` can trigger a null pointer exception, and in some cases, it may cause logical short-circuiting.
h3. Dev Design

the behavior change is reasonable, but some parts of the code were not thoroughly modified and require further refinement.  
In the realization selection process, the previous behavior was:

!image-2025-02-18-17-33-11-649.png|width=553,height=251!

After the modification, the expected behavior is:

!image-2025-02-18-17-33-47-075.png|width=685,height=337!

Some step cases need to be adapted, and certain logic (e.g., exact match judgment logic) requires adjustment.

> Errors in building and querying real-time models
> ------------------------------------------------
>
>                 Key: KYLIN-5997
>                 URL: https://issues.apache.org/jira/browse/KYLIN-5997
>             Project: Kylin
>          Issue Type: Bug
>    Affects Versions: 5.0.0
>            Reporter: Guoliang Sun
>            Priority: Major
>         Attachments: image-2025-02-18-17-33-11-649.png, image-2025-02-18-17-33-47-075.png
>
>




--
This message was sent by Atlassian Jira
(v8.20.10#820010)