Basic question regarding calculating number of reducers

Hi, I have a basic question regarding the calculation of the number of reducers in hive. I know that is computed as /. In case of compressed files it is not clear whether total input size is calculated when compressed or decompressed. Doesn't it make a significant difference if calculated when co

Determining the number of buckets in hive

Hi, I know this question might have been beaten to death, but I could not find an answer to a particular question. I'm using hive 0.10.x I have a table partitioned on day and I would like to bucket the table on a different column to avail of the SMB join optimization. I have seen an earlier threa

Question regarding cluster by multiple columns

Hi, I'm studying the bucketed tables as an option for my storage. What would be use case where it is useful to cluster by multiple columns? I 'm trying to solve a problem of optimizing a join between two tables with filtering. Let's say Table A has columns (id, country, .) and table has colu

Re: Using Cluster by to improve Group by Performance

Any response or pointers to understand how Cluster By in sub queries can affect the performance/speed of outer queries is helpful. Thanks Kay On Mon, Oct 28, 2013 at 1:17 PM, KayVajj wrote: > Hi, > > I have a question if I could use the cluster by clause in a sub query to >

Using Cluster by to improve Group by Performance

Hi, I have a question if I could use the cluster by clause in a sub query to improve the performance of a group by query in hive Lets I have a Table A with columns (all strings) col1..col5 and the table is not "Clustered" now I 'm trying to run the below query select > col1, > col2, > col3, > c

What is the use of compressed field in the hive storage descriptor

A desc extended command results in the following Table( tableName:table_namet, dbName:cybs_test, owner:x...@abc.com, createTime:1380232668, lastAccessTime:0, retention:0, sd:StorageDescriptor( cols:[ FieldSchema(name:a, type:string, comment:null), FieldSchema(name:b, type:string, comment:nul

non-string partition column types is it discouraged

I have a question regarding the partition column types in a Hive table. We run hive 0.9.0 in a cloudera distribution and we're having issue trying to connect to hive using the Cloudera Tableau ODBC Connector. I'm unable to use a partition column of type int. Trying to find a solution I chanced upo