[DRILL-861] sum(decimal38) gives wrong result, even without overflowing

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.4.0
• Component/s: Functions - Drill
• Assignee: DrillCommitter
• Reporter: Chun Chang
• Created: 29/May/14 21:55
• Updated: 09/Jul/14 17:58
• Resolved: 08/Jul/14 01:04

Description

#Wed May 28 17:19:59 PDT 2014
git.commit.id.abbrev=c8a08c3

sum over decimal38 type of data gives wrong result. this is without encounter overflowing.

I have the following data in a decimal38 column:

0: jdbc:drill:schema=dfs> select cast(c_decimal38 as decimal(38,14)) from data where c_row <= 14;
------------

EXPR$0

------------

0E-14
1.00000000000000
123456789.00000000000000
999999999.00000000000000
-999999999.00000000000000
1.000000E-8
-1.000000E-8
12345.67890000000000
123456789.12345678900000
999999999999999999.00000000000000
-999999999999999999.00000000000000
0E-14
0E-14
12345678901234.12345678901234

------------
14 rows selected (0.288 seconds)

The sum of the columns gives the following wrong number:

0: jdbc:drill:schema=dfs> select sum(cast(c_decimal38 as decimal(38,14))) from data where c_row <= 14;
------------

EXPR$0

------------

1.2345925827186123E13

The correct number should be (from postgres, I also hand calculated):

foodmart=# select sum(cast(c_decimal38 as decimal(38,14))) from data where c_row <= 14;
sum
-------------------------------
12345925827158.92581357801234

Issue Links

• is a clone of: DRILL-1040 sum(decimal28) gives wrong result