wangsheng has uploaded a new patch set (#3). ( http://gerrit.cloudera.org:8080/17933 )
Change subject: IMPALA-10836: Add 'SimplifyCastExprRule' rule to rewrite cast expr in some situations ...................................................................... IMPALA-10836: Add 'SimplifyCastExprRule' rule to rewrite cast expr in some situations This patch adds a new expr rewrite rule to simplify some cast expr when cast target data type is the same as inner expr data type. We will remove unnecessary cast expr if any rules is matched. This kind of rewrite will improve query performance when casting a non-partition column, especially when scanning lots of data. Besides, cast expr in where clause can not pushdown to Kudu server, if we can remove unnecessary cast expr, Impala will pushdown this predicate to Kudu server, and this will save lots of time and IO/memmory. Testing: - Added unit test cases in `ExprRewriteRulesTest` Change-Id: Id8fac7100060d4e139a8b24d4795c6f279c55954 --- M fe/src/main/java/org/apache/impala/analysis/Analyzer.java A fe/src/main/java/org/apache/impala/rewrite/SimplifyCastExprRule.java M fe/src/test/java/org/apache/impala/analysis/ExprRewriteRulesTest.java 3 files changed, 139 insertions(+), 0 deletions(-) git pull ssh://gerrit.cloudera.org:29418/Impala-ASF refs/changes/33/17933/3 -- To view, visit http://gerrit.cloudera.org:8080/17933 To unsubscribe, visit http://gerrit.cloudera.org:8080/settings Gerrit-Project: Impala-ASF Gerrit-Branch: master Gerrit-MessageType: newpatchset Gerrit-Change-Id: Id8fac7100060d4e139a8b24d4795c6f279c55954 Gerrit-Change-Number: 17933 Gerrit-PatchSet: 3 Gerrit-Owner: wangsheng <[email protected]> Gerrit-Reviewer: Impala Public Jenkins <[email protected]> Gerrit-Reviewer: Quanlong Huang <[email protected]> Gerrit-Reviewer: Xianqing He <[email protected]> Gerrit-Reviewer: Zoltan Borok-Nagy <[email protected]>
