hadoop-hive-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Adam Kramer (JIRA)" <j...@apache.org>
Subject [jira] Updated: (HIVE-178) SELECT without FROM; dropping unnecessary table references
Date Mon, 15 Dec 2008 23:37:44 GMT

     [ https://issues.apache.org/jira/browse/HIVE-178?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

Adam Kramer updated HIVE-178:
-----------------------------

    Description: 
SELECT 1+1;

should just return '2', but instead hive fails because no table is listed.

SELECT 1+1 FROM (empty table);

should also just return '2', but instead hive "succeeds" because there is "no possible output,"
so it produces no output. This is the reason I filed under "bug" instead of "improvement:"
If it does not return '2' hive should fail.

So, currently we have to run 

SELECT 1+1 FROM (actual table with data);

...which runs a whole mapreduce step to ignore all of the data in the table before spitting
out '2'. This will be exceptionally frustrating if hadoop makes us wait for mapper(s).

It would be nice to be able to SELECT without specifying a table, and perhaps relatedly, to
be able to edit the above query (which worked) to not need to actually process (actual table
with data) given that no data is being pulled from it (as we see from the SELECT statement,
that table's name or alias does not appear).


  was:
SELECT 1+1;

should just return '2', but instead hive fails because no table is listed.

SELECT 1+1 FROM (empty table);

should also just return '2', but instead hive "succeeds" because there is no possible output,
so it produces no output.

So, currently we have to run 

SELECT 1+1 FROM (actual table with data);

...which runs a whole mapreduce step to ignore all of the data before spitting out '2'.

It would be nice to be able to SELECT without specifying a table, and perhaps relatedly, to
be able to edit the above query (which worked) to not need to actually process (actual table
with data) given that no data is being pulled from it (as we see from the SELECT statement,
that table's name or alias does not appear).

     Issue Type: Bug  (was: Improvement)

> SELECT without FROM; dropping unnecessary table references
> ----------------------------------------------------------
>
>                 Key: HIVE-178
>                 URL: https://issues.apache.org/jira/browse/HIVE-178
>             Project: Hadoop Hive
>          Issue Type: Bug
>          Components: Query Processor
>            Reporter: Adam Kramer
>
> SELECT 1+1;
> should just return '2', but instead hive fails because no table is listed.
> SELECT 1+1 FROM (empty table);
> should also just return '2', but instead hive "succeeds" because there is "no possible
output," so it produces no output. This is the reason I filed under "bug" instead of "improvement:"
If it does not return '2' hive should fail.
> So, currently we have to run 
> SELECT 1+1 FROM (actual table with data);
> ...which runs a whole mapreduce step to ignore all of the data in the table before spitting
out '2'. This will be exceptionally frustrating if hadoop makes us wait for mapper(s).
> It would be nice to be able to SELECT without specifying a table, and perhaps relatedly,
to be able to edit the above query (which worked) to not need to actually process (actual
table with data) given that no data is being pulled from it (as we see from the SELECT statement,
that table's name or alias does not appear).

-- 
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