hadoop-hive-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Edward Capriolo (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HIVE-1096) Hive Variables
Date Mon, 25 Jan 2010 20:49:34 GMT

    [ https://issues.apache.org/jira/browse/HIVE-1096?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12804701#action_12804701
] 

Edward Capriolo commented on HIVE-1096:
---------------------------------------

@Prasad,


I do not think we should do anything fancy here, just look for simple ${var} and replace with
var from session state. It could happen that ${ } could appear in a comment, but not very
likely.

>>String substitution will create problems with comments and also with error reporting.

Based on that we should make variables part of the grammar then?

In my example...
{noformat}
hive -hiveconf DAY=5 -e "LOAD DATA INFILE '/tmp/${DAY}'  into logs partition=${DAY}"
{noformat}
Can we make the grammar look inside a string like '/tmp/${DAY}' ?

> Hive Variables
> --------------
>
>                 Key: HIVE-1096
>                 URL: https://issues.apache.org/jira/browse/HIVE-1096
>             Project: Hadoop Hive
>          Issue Type: New Feature
>            Reporter: Edward Capriolo
>            Assignee: Edward Capriolo
>
> From mailing list:
> --Amazon Elastic MapReduce version of Hive seems to have a nice feature called "Variables."
Basically you can define a variable via command-line while invoking hive with -d DT=2009-12-09
and then refer to the variable via ${DT} within the hive queries. This could be extremely
useful. I can't seem to find this feature even on trunk. Is this feature currently anywhere
in the roadmap?--
> This could be implemented in many places.
> A simple place to put this is 
> in Driver.compile or Driver.run we can do string substitutions at that level, and further
downstream need not be effected. 
> There could be some benefits to doing this further downstream, parser,plan. but based
on the simple needs we may not need to overthink this.
> I will get started on implementing in compile unless someone wants to discuss this more.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


Mime
View raw message