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https://issues.apache.org/jira/browse/DRILL-4715?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15325101#comment-15325101
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Jinfeng Ni commented on DRILL-4715:
-----------------------------------

The testcase with large # of project expression was disabled in DRILL-1808, 
since the testcase also has long list of "order by". That's why we did not find 
this regression when DRILL-3912 was merged. 


> Java compilation error for a query with large number of expressions
> -------------------------------------------------------------------
>
>                 Key: DRILL-4715
>                 URL: https://issues.apache.org/jira/browse/DRILL-4715
>             Project: Apache Drill
>          Issue Type: Bug
>          Components: Execution - Codegen
>            Reporter: Jinfeng Ni
>
> The following query would hit compilation error, when Drill generates and 
> compiles the run-time code. 
> Q1 :
> {code}
> select  expr1, expr2, expr3, ...., exprN
> from table
> {code} 
> In Q1, expr1, expr2, ..., exprN are non-trivial expression (in stead of 
> simply column reference), and N is big enough, then the run-time generated 
> code may have a method which goes beyond the 64k limit imposed by JVM. 
> This seems to be a regression from DRILL-3912 (Common subexpression 
> elimination). CSE tries to put as many expressions in one block as possible, 
> to detect and eliminate as many CSE as possible. However, this implies we may 
> end up with big method with compilation error.
>     



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