thanks,

this is an external table; so at the DDL stage, there is no data loading that 
is happening. All that hive is supposed to do is to load the definition into 
mysql, right? Are you suggesting that it's reading the datafile in HDFS? That 
should not be happening since the "external table" does not need the data to be 
present, right?

 
Sincerely,


Ameet


________________________________
 From: Edward Capriolo <[email protected]>
To: [email protected]; ameet chaubal <[email protected]> 
Sent: Monday, January 16, 2012 10:06 AM
Subject: Re: large sql file creating large num of columns
 

I highly doubt this will work. I think that many things in hadoop and hive will 
try to buffer an entire row so even if you make it past the metastore I do not 
think it will be of any use. 

On Mon, Jan 16, 2012 at 9:42 AM, ameet chaubal <[email protected]> wrote:

Hi All,
>
>
>I have a SQL file of size 30mb which is a single create table statement with 
>about 800,000 columns, hence the size. 
>
>I am trying to execute it using hive -f <file>. Initially, hive ran the 
>command with 256mb heap size and gave me an OOM error. I increased the heap 
>size using export HADOOP_HEAPSIZE to 1 gb and eventually 2gb which made the 
>OOM error go away. However, the hive command ran for 5 hours without actually 
>creating the table. The JVM was running.
>However,
>1. running a strace on the process showed that it was stuck on a futex call.
>2. I am using mysql for metastore and there were no rows added to either TBLS 
>or COLUMNS table.
>
>
>Question.
>1. can hive do this create table of 800k columns from a sql file of 30mb?
>2. if theoretically possible, what could be happening that's taking it over 5 
>hours and still not succeeding?
>
>
>any insight is much appreciated.
> 
>Sincerely,
>
>
>Ameet
>

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