hive-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Jörn Franke <jornfra...@gmail.com>
Subject Re: clarification please
Date Thu, 29 Oct 2015 20:32:14 GMT

> On 29 Oct 2015, at 06:43, Ashok Kumar <ashok34668@yahoo.com> wrote:
> 
> hi gurus,
> 
> kindly clarify the following please
> 
> Hive currently does not support indexes or indexes are not used in the query
Not correct. See https://snippetessay.wordpress.com
> The lowest granularity for concurrency is partition. If table is partitioned, then partition
will be lucked in DML operation
Not correct for select queries. For all other queries see Hive transactions.
> What is the best file format to store Hive table in HDFS? Is this ORC or Avro that allow
being split and support block compression?
Depends on your needs. Avro is an exchange     format between different systems. ORC is very
efficient for everything related to sql type of analysis due to internal indexes, bloom filters
etc both Orc and avro support block compression for any compression algorithm
> Text/CSV files. By default if file type is not specified at creation time, Hive will
default to text file?
Depends how it is configured

> 
> 
> Thanks

Mime
View raw message