Thomas Tauber-Marshall has posted comments on this change.

Change subject: IMPALA-1861: Simplify conditionals with constant conditions
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Patch Set 8:

(4 comments)

http://gerrit.cloudera.org:8080/#/c/5585/7/fe/src/main/java/org/apache/impala/rewrite/SimplifyConditionalsRule.java
File fe/src/main/java/org/apache/impala/rewrite/SimplifyConditionalsRule.java:

Line 154:     // Contains all 'when' clauses with non-constant conditions, used 
to construct the new
> construct
Done


Line 157:     // Set to THEN of first constant TRUE clause, if any.
> comment: first constant true when clause
Done


Line 188:         } else {
> this can be misread to apply to the following else if
Done


Line 189:           // This WHEN is always FALSE, so it can be removed.
> can whenExpr be a null literal, given l160?
You're right - I was thinking of the hasCaseExpr case where whenExpr comes from 
the BinaryPredicate we construct and constant fold above, but I don't guess 
there's any expression of the form "non-null literal = non-null literal" that 
would constant fold down to NULL.


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Gerrit-MessageType: comment
Gerrit-Change-Id: Id70aaf9fd99f64bd98175b7e2dbba28f350e7d3b
Gerrit-PatchSet: 8
Gerrit-Project: Impala-ASF
Gerrit-Branch: master
Gerrit-Owner: Thomas Tauber-Marshall <[email protected]>
Gerrit-Reviewer: Alex Behm <[email protected]>
Gerrit-Reviewer: Bharath Vissapragada <[email protected]>
Gerrit-Reviewer: Marcel Kornacker <[email protected]>
Gerrit-Reviewer: Thomas Tauber-Marshall <[email protected]>
Gerrit-Reviewer: Tim Armstrong <[email protected]>
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