Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
Avro, mail # user - Globbing several AVRO files with different (extended) schemes


Copy link to this message
-
Re: Globbing several AVRO files with different (extended) schemes
Scott Carey 2012-03-20, 21:08
I'm assuming you are using Pig's AvroStorage function. It appears that it
does not support schema migration, but it certainly could do so.  A
collection of avro files can be 'viewed' as if they all are of one schema
provided they can all resolve to it.  I have several tools that do this
successfully with MapReduce/Pig/Hive.

The Pig AvroStorage tool is maintained by the Apache Pig project, you will
need to inquire there in order to get more details.

-Scott

On 3/20/12 2:27 AM, "Markus Resch" <[EMAIL PROTECTED]> wrote:

>Hi guys,
>
>Thanks again for your awesome hint about sqoop.
>
>I have another question: The Data I'm working with is stored as AVRO
>Files in the Hadoop. When I try to glob them everything works just
>perfectly. But. When I add the schema of a single data file while the
>others remain everything gets wrecked:
>
>"currently we assume all avro files under the same "location"
>     * share the same schema and will throw exception if not."
>
>(e.g. I add a new data field) Expected behavior for me would be: If I'm
>globbing several files with slightly different schema the result of the
>LOAD would be either return an intersection of all valid fields that are
>common to both schemes or the atoms of the missing fields are nulled.
>
>How could I handle this properly?
>
>Thanks
>
>Markus
>
>
>
>