impala-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Taras Bobrovytsky (Code Review)" <ger...@cloudera.org>
Subject [Impala-CR](cdh5-trunk) IMPALA-3163: Fix Decimal to Timestamp casting
Date Tue, 17 May 2016 22:55:33 GMT
Taras Bobrovytsky has uploaded a new patch set (#6).

Change subject: IMPALA-3163: Fix Decimal to Timestamp casting
......................................................................

IMPALA-3163: Fix Decimal to Timestamp casting

Before this patch, we would first convert the Decimal to Double, then
Double to Timestamp. This resulted in imprecise results.

I ran a benchmark where we read decimal values from a large parquet
table and cast them to timestamp. This implementation is slightly
slower than the current implementation (70 seconds vs 96 seconds). This
issue can probably be fixed with codegen.

Change-Id: Iabeea9f4ab4880b2f814408add63c77916e2dba9
---
M be/src/exprs/decimal-operators-ir.cc
M be/src/exprs/expr-test.cc
2 files changed, 19 insertions(+), 5 deletions(-)


  git pull ssh://gerrit.cloudera.org:29418/Impala refs/changes/91/2791/6
-- 
To view, visit http://gerrit.cloudera.org:8080/2791
To unsubscribe, visit http://gerrit.cloudera.org:8080/settings

Gerrit-MessageType: newpatchset
Gerrit-Change-Id: Iabeea9f4ab4880b2f814408add63c77916e2dba9
Gerrit-PatchSet: 6
Gerrit-Project: Impala
Gerrit-Branch: cdh5-trunk
Gerrit-Owner: Taras Bobrovytsky <tbobrovytsky@cloudera.com>
Gerrit-Reviewer: Alex Behm <alex.behm@cloudera.com>

Mime
View raw message