[
https://issues.apache.org/jira/browse/HIVE-837?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12790263#action_12790263
]
Carl Steinbach commented on HIVE-837:
-------------------------------------
I think this can be implemented as either a UDF or virtual column as long as we
choose to define FILE() as the directory path that contains the
table's/partition's data files, but I think things get significantly more
complicated if we want FILE() to evaluate to the actual *file* that the current
row is drawn from. At compile-time we have access to the table/partition
directory and can retrieve a list of data files, but I don't think it is
possible to make the row<->File association until runtime. Does this make sense
or am I missing something?
> virtual column support (filename) in hive
> -----------------------------------------
>
> Key: HIVE-837
> URL: https://issues.apache.org/jira/browse/HIVE-837
> Project: Hadoop Hive
> Issue Type: New Feature
> Components: Query Processor
> Reporter: Namit Jain
>
> Copying from some mails:
> I am dumping files into a hive partion on five minute intervals. I am using
> LOAD DATA into a partition.
> weblogs
> web1.00
> web1.05
> web1.10
> ...
> web2.00
> web2.05
> web1.10
> ....
> Things that would be useful..
> Select files from the folder with a regex or exact name
> select * FROM logs where FILENAME LIKE(WEB1*)
> select * FROM LOGS WHERE FILENAME=web2.00
> Also it would be nice to be able to select offsets in a file, this would make
> sense with appends
> select * from logs WHERE FILENAME=web2.00 FROMOFFSET=454644 [TOOFFSET=]
> select
> substr(filename, 4, 7) as class_A,
> substr(filename, 8, 10) as class_B
> count( x ) as cnt
> from FOO
> group by
> substr(filename, 4, 7),
> substr(filename, 8, 10) ;
> Hive should support virtual columns
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
