Sent: Monday, April 30, 2012 1:08 PM
To: user@hive.apache.org
Subject: Re: How to make the query compiler not determine the number of
reducers?
You are trying to create a Cartesian product.
select * FROM table1,table2
should do that. You do not need a join clause.
On Mon, Apr 30, 2012 at 12:53 PM
How to make the query compiler not determine the number of
reducers?
Thomas,
It needn't be the case, raising your map tasks may not have any effect
on reduce tasks. May be we can help you out if you could provide some
details like :
- the query you are executing
- describe formatted on t
er of reducers for you. But you can
easily override them at CLI. Before executing your query
hive>SET mapred.reduce.tasks=n;
Where n is the required num of reducers.
Regards
Bejoy KS
Sent from handheld, please excuse typos.
_
From: "Ryabin, Thomas"
Date: Fri, 27 Apr 2012
Hi,
When I run a query that uses a custom UDF I made, one of the lines it
prints out is:
Number of reduce tasks determined at compile time: 1
And this causes the MapReduce job to have only 1 reducer. Is there a way
to make it so the compiler does not determine the number of reduce tasks
to
I figured out how to do this. The problem is that you need to add the
number of fields you want to be returned to the
StandardStructObjectInspector that is returned in the initialize()
method of the UDTF.
-Thomas
From: Ryabin, Thomas
Sent: Tuesday, April 24, 2012 12:46 PM
To: user
Hello,
I have created a custom UDTF called "test_udtf". This function takes 4
parameters. Right now I can use this function like so in the following
query:
SELECT test_udtf(product, store, 'test0', 'test1') as (col0, col1, col2,
col3) from products join stores;
The problem is that I want t
programmatic approach for doing this and
provide hive with a final query.
You can solve this with either solving your regular expression outside
hive paradigm and then provide the query to hive
On 4/23/12, Ryabin, Thomas wrote:
> Hi,
>
>
>
> I know that it is possible to use regex colum
Hi,
I know that it is possible to use regex column specification with the
SELECT clause like so:
SELECT `employee.*` FROM employees;
I was wondering if it is possible to use it with the WHERE clause also.
For example I want to create the query:
SELECT `employee.*` FROM employees WHERE $1
