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https://issues.apache.org/jira/browse/HIVE-951?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12782548#action_12782548
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Prasad Chakka commented on HIVE-951:
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@namit, I agree with others that this would be very convenient and useful
functionality for external tables. external table data and location consistency
is left to be managed by users. so changing the fileset in that location is not
a Hive problem. Hive will query the location and get the list of paths at the
time the query is being executed. if a file gets removed or added and query
fails because of a deleted file, it is user's responsibility.
> Selectively include EXTERNAL TABLE source files via REGEX
> ---------------------------------------------------------
>
> Key: HIVE-951
> URL: https://issues.apache.org/jira/browse/HIVE-951
> Project: Hadoop Hive
> Issue Type: Improvement
> Components: Query Processor
> Reporter: Carl Steinbach
>
> CREATE EXTERNAL TABLE should allow users to cherry-pick files via regular
> expression.
> CREATE EXTERNAL TABLE was designed to allow users to access data that exists
> outside of Hive, and
> currently makes the assumption that all of the files located under the
> supplied path should be included
> in the new table. Users frequently encounter directories containing multiple
> datasets, or directories that contain data in heterogeneous schemas, and it's
> often
> impractical or impossible to adjust the layout of the directory to meet the
> requirements of
> CREATE EXTERNAL TABLE. A good example of this problem is creating an external
> table based
> on the contents of an S3 bucket.
> One way to solve this problem is to extend the syntax of CREATE EXTERNAL TABLE
> as follows:
> CREATE EXTERNAL TABLE
> ...
> LOCATION path [file_regex]
> ...
> For example:
> {code:sql}
> CREATE EXTERNAL TABLE mytable1 ( a string, b string, c string )
> STORED AS TEXTFILE
> LOCATION 's3://my.bucket/' 'folder/2009.*\.bz2$';
> {code}
> Creates mytable1 which includes all files in s3:/my.bucket with a filename
> matching 'folder/2009*.bz2'
> {code:sql}
> CREATE EXTERNAL TABLE mytable2 ( d string, e int, f int, g int )
> STORED AS TEXTFILE
> LOCATION 'hdfs://data/' 'xyz.*2009????.bz2$';
> {code}
> Creates mytable2 including all files matching 'xyz*2009????.bz2' located
> under hdfs://data/
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