[HIVE-6140] trim udf is very slow

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: UDF
• Assignee: Anandha L Ranganathan
• Reporter: Thejas Nair
• Created: 04/Jan/14 01:04
• Updated: 11/Jan/14 20:10

Description

Paraphrasing what was reported by cartershanklin -

I used the attached Perl script to generate 500 million two-character strings which always included a space. I loaded it using:
create table letters (l string);
load data local inpath '/home/sandbox/data.csv' overwrite into table letters;
Then I ran this SQL script:
select count(l) from letters where l = 'l ';
select count(l) from letters where trim(l) = 'l';

First query = 170 seconds
Second query = 514 seconds