Gopal V created HIVE-14573:
------------------------------
Summary: Vectorization: Implement StringExpr::find()
Key: HIVE-14573
URL: https://issues.apache.org/jira/browse/HIVE-14573
Project: Hive
Issue Type: Bug
Reporter: Gopal V
Currently, the LIKE expression implementation is a dump StringExpr::equals()
loop.
For an input of N bytes and a pattern of M bytes, this has the complexity of
((N-M)*M), which is not an issue with small patterns or small inputs.
The pattern matching is currently optimized for matches, while in clickstream
data the opposite is true in general.
>From the common crawl data, the following run will go through the same
{code}
select count(1) from uservisits_orc_data where useragent like "%Opera%" and
searchword LIKE "%fruit%";
{code}
--
This message was sent by Atlassian JIRA
(v6.3.4#6332)
