[
https://issues.apache.org/jira/browse/DRILL-3477?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16875961#comment-16875961
]
ASF GitHub Bot commented on DRILL-3477:
---------------------------------------
arina-ielchiieva commented on pull request #84: DRILL-3477: Use varbinary for
null vectors
URL: https://github.com/apache/drill/pull/84
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
[email protected]
> Using IntVector for null expressions causes problems with implicit cast
> -----------------------------------------------------------------------
>
> Key: DRILL-3477
> URL: https://issues.apache.org/jira/browse/DRILL-3477
> Project: Apache Drill
> Issue Type: Bug
> Reporter: Steven Phillips
> Assignee: Jinfeng Ni
> Priority: Major
>
> See DRILL-3353, for example.
> A simple example is this:
> {code}
> select * from t where a = 's';
> {code}
> If the first batch scanned from table t does not contain the column a, the
> expression materializer in Project defaults to Nullable Int as the type. The
> Filter then sees an Equals expression between a VarChar and an Int type, so
> it does an implicit cast. Implicit cast rules give Int higher precedence, so
> the literal 's' is cast to Int, which ends up throwing a
> NumberFormatException.
> In the class ResolverTypePrecedence, we see that Null type has the lowest
> precedence, which makes sense. But since we don't actually currently have an
> implementation for NullVector, we should materialize the Null type as the
> Vector with the lowest possible precedence, which is VarBinary.
> My suggestion is that we should use VarBinary as the default type in
> ExpressionMaterializer instead of Int.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
