[IMPALA-112] Wrong result Double value using "insert overwrite ~ select"

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Impala 0.6
• Fix Version/s: Impala 0.7
• Assignee: Nong Li
• Reporter: Daisuke Kobayashi
• Created: 06/Mar/13 09:22
• Updated: 20/Dec/15 00:04
• Resolved: 05/Apr/13 05:03

Description

Wrong result of double value returns after executing "insert overwrite ~ select" in Impala while it doesn't run into the trouble using Hive. Correct value should be returned as well as doing with Hive. To reproduce this issue, follow the below steps:

 # hive -e "create table t1 (v double);"
 # hive -e "create table t2 (v double);"
 # echo "12.34567" > /tmp/data.txt
 # hive -e "load data local inpath '/tmp/data.txt' into table t1;"
 # impala-shell --impalad=127.0.0.1:21000 --query="select v from t1;"

This may return the correct value as "12.34567".

# impala-shell --impalad=127.0.0.1:21000 --query="insert overwrite table t2 select * from t1;"
# impala-shell --impalad=127.0.0.1:21000 --query="select v from t2;"

This would returns the wronge value as "12.3457". It might be a bug. Meanwhile, we can get the correct value if "insert overwrite ~ select" using HiveQL:

# hive -e "create table t3 (v double);"
# hive -e "insert into table t3 select * from t1;"
# impala-shell --impalad=127.0.0.1:21000 --query="select v from t3;"

This returns the correct value as "12.34567".